Network Working Group A. Siddiqui
Request for Comments: 4712 D. Romascanu
Category: Standards Track Avaya
E. Golovinsky
Alert Logic
M. Rahman
Samsung Information Systems America
Y. Kim
Broadcom
October 2006
Transport Mappings for Real-time Application Quality-of-Service
Monitoring (RAQMON) Protocol Data Unit (PDU)
Status of This Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2006).
Abstract
This memo specifies two transport mappings of the Real-Time
Application Quality-of-Service Monitoring (RAQMON) information model
defined in RFC 4710 using TCP as a native transport and the Simple
Network Management Protocol (SNMP) to carry the RAQMON information
from a RAQMON Data Source (RDS) to a RAQMON Report Collector (RRC).
Siddiqui, et al. Standards Track [Page 1]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Table of Contents 1. Introduction ....................................................3 2. Transporting RAQMON Protocol Data Units .........................3 2.1. TCP as an RDS/RRC Network Transport Protocol ...............3 2.1.1. The RAQMON PDU ......................................5 2.1.2. The BASIC Part of the RAQMON Protocol Data Unit .....7 2.1.3. APP Part of the RAQMON Protocol Data Unit ..........14 2.1.4. Byte Order, Alignment, and Time Format of RAQMON PDUs ........................................15 2.2. Securing RAQMON Session ...................................15 2.2.1. Sequencing of the Start TLS Operation ..............18 2.2.2. Closing a TLS Connection ...........................21 2.3. SNMP Notifications as an RDS/RRC Network Transport Protocol ..................................................22 3. IANA Considerations ............................................38 4. Congestion-Safe RAQMON Operation ...............................38 5. Acknowledgements ...............................................39 6. Security Considerations ........................................39 6.1. Usage of TLS with RAQMON ..................................41 6.1.1. Confidentiality & Message Integrity ................41 6.1.2. TLS CipherSuites ...................................41 6.1.3. RAQMON Authorization State .........................42 7. References .....................................................43 7.1. Normative References ......................................43 7.2. Informative References ....................................44 Appendix A. Pseudocode ............................................46 Siddiqui, et al. Standards Track [Page 2]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 1. Introduction The Real-Time Application QoS Monitoring (RAQMON) Framework, as outlined by [RFC4710], extends the Remote Monitoring family of protocols (RMON) by defining entities such as RAQMON Data Sources RDS) and RAQMON Report Collectors (RRC) to perform various application monitoring in real time. [RFC4710] defines the relevant metrics for RAQMON monitoring carried by the common protocol data unit (PDU) used between a RDS and RRC to report QoS statistics. This memo contains a syntactical description of the RAQMON PDU structure. The following sections of this memo contain detailed specifications for the usage of TCP and SNMP to carry RAQMON information. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119]. 2. Transporting RAQMON Protocol Data Units The RAQMON Protocol Data Unit (PDU) utilizes a common data format understood by the RDS and the RRC. A RAQMON PDU does not transport application data but rather occupies the place of a payload specification at the application layer of the protocol stack. As part of the specification, this memo also specifies the usage of TCP and SNMP as underlying transport protocols to carry RAQMON PDUs between RDSs and RRCs. While two transport protocol choices have been provided as options to chose from for RDS implementers, RRCs MUST implement the TCP transport and MAY implement the SNMP transport. 2.1. TCP as an RDS/RRC Network Transport Protocol A transport binding using TCP is included within the RAQMON specification to facilitate reporting from various types of embedded devices that run applications such as Voice over IP, Voice over Wi-Fi, Fax over IP, Video over IP, Instant Messaging (IM), E-mail, software download applications, e-business style transactions, web access from wired or wireless computing devices etc. For many of these devices, PDUs and a TCP-based transport fit the deployment needs. The RAQMON transport requirements for end-to-end congestion control and reliability are inherently built into TCP as a transport protocol [RFC793]. Siddiqui, et al. Standards Track [Page 3]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 To use TCP to transport RAQMON PDUs, it is sufficient to send the PDUs as TCP data. As each PDU carries its length, the receiver can determine the PDU boundaries. The following section details the RAQMON PDU specifications. Though transmitted as one Protocol Data Unit, a RAQMON PDU is functionally divided into two different parts: the BASIC part and application extensions required for vendor-specific extension [RFC4710]. Both functional parts follow a field carrying a SMI Network Management Private Enterprise code currently maintained by IANA http://www.iana.org/assignments/enterprise-numbers, which is used to identify the organization that defined the information carried in the PDU. A RAQMON PDU in the current version is marked as PDU Type (PDT) = 1. The parameters carried by RAQMON PDUs are shown in Figure 1 and are defined in section 5 of [RFC4710]. Vendors MUST use the BASIC part of the PDU to report parameters pre- listed here in the specification for interoperability, as opposed to using the application-specific portion. Vendors MAY also use application-specific extensions to convey application-, vendor-, or device-specific parameters not included in the BASIC part of the specification and explicitly publish such data externally to attain extended interoperability. Siddiqui, et al. Standards Track [Page 4]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 2.1.1. The RAQMON PDU 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |PDT = 1 |B| T |P|S|R| RC | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DSRC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SMI Enterprise Code = 0 |Report Type = 0| RC_N | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |flag +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Data Source Address {DA} | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Receiver's Address (RA) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | NTP Timestamp, most significant word | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | NTP Timestamp, least significant word | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Application Name (AN) ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Data Source Name (DN) ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Receiver's Name (RN) ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Length | Session State ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session Duration | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Round-Trip End-to-End Network Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | One-Way End-to-End Network Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Cumulative Packet Loss | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Cumulative Application Packet Discard | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Total # Application Packets sent | Siddiqui, et al. Standards Track [Page 5]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Total # Application Packets received | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Total # Application Octets sent | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Total # Application Octets received | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Data Source Device Port Used | Receiver Device Port Used | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | S_Layer2 | S_Layer3 | S_Layer2 | S_Layer3 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Source Payload |Receiver | CPU | Memory | |Type |Payload Type | Utilization | Utilization | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Session Setup Delay | Application Delay | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | IP Packet Delay Variation | Inter arrival Jitter | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Packet Discrd | Packet loss | Padding | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SMI Enterprise Code = "xxx" | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Report Type = "yyy" | Length of Application Part | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | application/vendor specific extension | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ............... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ............... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ............... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SMI Enterprise Code = "abc" | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Report Type = "zzz" | Length of Application Part | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | application/vendor specific extension | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | ............... | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 1: RAQMON Protocol Data Unit Siddiqui, et al. Standards Track [Page 6]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 2.1.2. The BASIC Part of the RAQMON Protocol Data Unit A RAQMON PDU must contain the following BASIC part fields at all times: PDU type (PDT): 5 bits - This indicates the type of RAQMON PDU being sent. PDT = 1 is used for the current RAQMON PDU version defined in this document. basic (B): 1 bit - While set to 1, the basic flag indicates that the PDU has BASIC part of the RAQMON PDU. A value of zero is considered valid and indicates a RAQMON NULL PDU. trailer (T): 3 bits - Total number of Application-Specific Extensions that follow the BASIC part of RAQMON PDU. A value of zero is considered valid as many times as there is no application- specific information to add to the basic information. padding (P): 1 bit - If the padding bit is set, the BASIC part of the RAQMON PDU contains some additional padding octets at the end of the BASIC part of the PDU that are not part of the monitoring information. Padding may be needed in some cases, as reporting is based on the intent of a RDS to report certain parameters. Also, some parameters may be reported only once at the beginning of the reporting session, e.g., Data Source Name, Receiver Name, payload type, etc. Actual padding at the end of the BASIC part of the PDU is 0, 8, 16, or 24 bits to make the length of the BASIC part of the PDU a multiple of 32 bits Source IP version Flag (S): 1 bit - While set to 1, the source IP version flag indicates that the Source IP address contained in the PDU is an IPv6 address. Receiver IP version Flag (R): 1 bit - While set to 1, the receiver IP version flag indicates that the receiver IP address contained in the PDU is an IPv6 address. record count (RC): 4 bits - Total number of application records contained in the BASIC part of the PDU. A value of zero is considered valid but useless, with the exception of the case of a NULL PDU indicating the end of a RDS reporting session. length: 16 bits (unsigned integer) - The length of the BASIC part of the RAQMON PDU in units of 32-bit words minus one; this count includes the header and any padding. Siddiqui, et al. Standards Track [Page 7]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 DSRC: 32 bits - Data Source identifier represents a unique RAQMON reporting session descriptor that points to a specific reporting session between RDS and RRC. Uniqueness of DSRC is valid only within a reporting session. DSRC values should be randomly generated using vendor-chosen algorithms for each communication session. It is not sufficient to obtain a DSRC simply by calling random() without carefully initializing the state. One could use an algorithm like the one defined in Appendix A.6 in [RFC3550] to create a DSRC. Depending on the choice of algorithm, there is a finite probability that two DSRCs from two different RDSs may be the same. To further reduce the probability that two RDSs pick the same DSRC for two different reporting sessions, it is recommended that an RRC use parameters like Data Source Address (DA), Data Source Name (DN), and layer 2 Media Access Control (MAC) Address in the PDU in conjunction with a DSRC value. It is not mandatory for RDSs to send parameters like Data Source Address (DA), Data Source Name (DN), and MAC Address in every PDU sent to RRC, but occasionally sending these parameters will reduce the probability of DSRC collision drastically. However, this will cause an additional overhead per PDU. A value of zero for basic (B) bit and trailer (T) bits constitutes a RAQMON NULL PDU (i.e., nothing to report). RDSs MUST send a RAQMON NULL PDU to RRC to indicate the end of the RDS reporting session. A NULL PDU ends with the DSRC field. SMI Enterprise Code: 16 bits. A value of SMI Enterprise Code = 0 is used to indicate the RMON-WG-compliant BASIC part of the RAQMON PDU format. Report Type: 8 bits - These bits are reserved by the IETF RMON Working Group. A value of 0 within SMI Enterprise Code = 0 is used for the version of the PDU defined by this document. The BASIC part of each RAQMON PDU consists of Record Count Number (RC_N) and RAQMON Parameter Presence Flags (RPPF) to indicate the presence of appropriate RAQMON parameters within a record, as defined in Table 1. RC_N: 8 bits - The Record Count number indicates a sub-session within a communication session. A value of zero is a valid record number. The maximum number of records that can be described in one RAQMON Packet is 256. RAQMON Parameter Presence Flags (RPPF): 32 bits Each of these flags, while set, represents that this RAQMON PDU contains corresponding parameters as specified in Table 1. Siddiqui, et al. Standards Track [Page 8]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 +----------------+--------------------------------------------------+ | Bit Sequence | Presence/Absence of corresponding Parameter | | Number | within this RAQMON PDU | +----------------+--------------------------------------------------+ | 0 | Data Source Address (DA) | | | | | 1 | Receiver Address (RA) | | | | | 2 | NTP Timestamp | | | | | 3 | Application Name | | | | | 4 | Data Source Name (DN) | | | | | 5 | Receiver Name (RN) | | | | | 6 | Session Setup Status | | | | | 7 | Session Duration | | | | | 8 | Round-Trip End-to-End Net Delay (RTT) | | | | | 9 | One-Way End-to-End Network Delay (OWD) | | | | | 10 | Cumulative Packets Loss | | | | | 11 | Cumulative Packets Discards | | | | | 12 | Total number of App Packets sent | | | | | 13 | Total number of App Packets received | | | | | 14 | Total number of App Octets sent | | | | | 15 | Total number of App Octets received | | | | | 16 | Data Source Device Port Used | | | | | 17 | Receiver Device Port Used | | | | | 18 | Source Layer 2 Priority | | | | | 19 | Source Layer 3 Priority | | | | | 20 | Destination Layer 2 Priority | | | | | 21 | Destination Layer 3 Priority | | | | Siddiqui, et al. Standards Track [Page 9]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 | 22 | Source Payload Type | | | | | 23 | Receiver Payload Type | | | | | 24 | CPU Utilization | | | | | 25 | Memory Utilization | | | | | 26 | Session Setup Delay | | | | | 27 | Application Delay | | | | | 28 | IP Packet Delay Variation | | | | | 29 | Inter arrival Jitter | | | | | 30 | Packet Discard (in fraction) | | | | | 31 | Packet Loss (in fraction) | +----------------+--------------------------------------------------+ Table 1: RAQMON Parameters and Corresponding RPPF Data Source Address (DA): 32 bits or 160 bits in binary representation - This parameter is defined in section 5.1 of [RFC4710]. IPv6 addresses are incorporated in Data Source Address by setting the source IP version flag (S bit) of the RAQMON PDU header to 1. Receiver Address (RA): 32 bits or 160 bits - This parameter is defined in section 5.2 of [RFC4710]. It follows the exact same syntax as Data Source Address but is used to indicate a Receiver Address. IPv6 addresses are incorporated in Receiver Address by setting the receiver IP version flag (R bit) of the RAQMON PDU header to 1. Session Setup Date/Time (NTP timestamp): 64 bits - This parameter is defined in section 5.7 of [RFC4710] and represented using the timestamp format of the Network Time Protocol (NTP), which is in seconds [RFC1305]. The full resolution NTP timestamp is a 64-bit unsigned fixed-point number with the integer part in the first 32 bits and the fractional part in the last 32 bits. Application Name: This parameter is defined in section 5.32 of [RFC4710]. The Application Name field starts with an 8-bit octet count describing the length of the text followed by the text itself using UTF-8 encoding. Application Name field is a multiple of 32 bits, and padding will be used if necessary. Siddiqui, et al. Standards Track [Page 10]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 A Data Source that does not support NTP SHOULD set the appropriate RAQMON flag to 0 to avoid wasting 64 bits in the PDU. Since the NTP time stamp is intended to provide the setup Date/Time of a session, it is RECOMMENDED that the NTP Timestamp be used only in the first RAQMON PDU after sub-session RC_N setup is completed, in order to use network resources efficiently. Data Source Name (DN): Defined in section 5.3 of [RFC4710]. The Data Source Name field starts with an 8-bit octet count describing the length of the text followed by the text itself. Padding is used to ensure that the length and text encoding occupy a multiple of 32 bits in the DN field of the PDU. The text MUST NOT be longer than 255 octets. The text is encoded according to the UTF-8 encoding specified in [RFC3629]. Applications SHOULD instruct RDSs to send out the Data Source Name infrequently to ensure efficient usage of network resources as this parameter is expected to remain constant for the duration of the reporting session. Receiver Name (RN): This metric is defined in section 5.4 of [RFC4710]. Like Data Source Name, the Receiver Name field starts with an 8-bit octet count describing the length of the text, followed by the text itself. The Receiver Name, including the length field encoding, is a multiple of 32 bits and follows the same padding rules as applied to the Data Source Name. Since the Receiver Name is expected to remain constant during the entire reporting session, this information SHOULD be sent out occasionally over random time intervals to maximize success of reaching a RRC and also conserve network bandwidth. Session Setup Status: The Session (sub-session) Setup Status is defined in section 5.10 of [RFC4710]. This field starts with an 8-bit length field followed by the text itself. Session Setup Status is a multiple of 32 bits. Session Duration: 32 bits - The Session (sub-session) Duration metric is defined in section 5.9 of [RFC4710]. Session Duration is an unsigned integer expressed in seconds. Round-Trip End-to-End Network Delay: 32 bits - The Round-Trip End- to-End Network Delay is defined in section 5.11 of [RFC4710]. This field represents the Round-Trip End-to-End Delay of sub- session RC_N, which is an unsigned integer expressed in milliseconds. One-Way End-to-End Network Delay: 32 bits - The One-Way End-to-End Network Delay is defined in section 5.12 of [RFC4710]. This field represents the One-Way End-to-End Delay of sub-session RC_N, which is an unsigned integer expressed in milliseconds. Siddiqui, et al. Standards Track [Page 11]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Cumulative Application Packet Loss: 32 bits - This parameter is defined in section 5.20 of [RFC4710] as an unsigned integer, representing the total number of packets from sub-session RC_N that have been lost while this RAQMON PDU was generated. Cumulative Application Packet Discards: 32 bits - This parameter is defined in section 5.22 of [RFC4710] as an unsigned integer representing the total number of packets from sub-session RC_N that have been discarded while this RAQMON PDU was generated. Total number of Application Packets sent: 32 bits - This parameter is defined in section 5.17 of [RFC4710] as an unsigned integer, representing the total number of packets transmitted within sub- session RC_N by the sender. Total number of Application Packets received: 32 bits - This parameter is defined in section 5.16 of [RFC4710] and is represented as an unsigned integer representing the total number of packets transmitted within sub-session RC_N by the receiver. Total number of Application Octets sent: 32 bits - This parameter is defined in section 5.19 of [RFC4710] as an unsigned integer, representing the total number of payload octets (i.e., not including header or padding) transmitted in packets by the sender within sub-session RC_N. Total number of Application Octets received: 32 bits - This parameter is defined in section 5.18 of [RFC4710] as an unsigned integer representing the total number of payload octets (i.e., not including header or padding) transmitted in packets by the receiver within sub-session RC_N. Data Source Device Port Used: 16 bits - This parameter is defined in section 5.5 of [RFC4710] and describes the port number used by the Data Source as used by the application in RC_N session while this RAQMON PDU was generated. Receiver Device Port Used: 16 bits - This parameter is defined in section 5.6 of [RFC4710] and describes the receiver port used by the application to communicate to the receiver. It follows same syntax as Source Device Port Used. S_Layer2: 8 bits - This parameter, defined in section 5.26 of [RFC4710], is associated to the source's IEEE 802.1D [IEEE802.1D] priority tagging of traffic in the communication sub-session RC_N. Since IEEE 802.1 priority tags are 3 bits long, the first 3 bits of this parameter represent the IEEE 802.1 tag value, and the last 5 bits are padded to 0. Siddiqui, et al. Standards Track [Page 12]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 S_Layer3: 8 bits - This parameter, defined in section 5.27 of [RFC4710], represents the layer 3 QoS marking used to send packets to the receiver by this data source during sub-session RC_N. D_Layer2: 8 bits - This parameter, defined in section 5.28 of [RFC4710], represents layer 2 IEEE 802.1D priority tags used by the receiver to send packets to the data source during sub-session RC_N session if the Data Source can learn such information. Since IEEE 802.1 priority tags are 3 bits long, the first 3 bits of this parameter represent the IEEE 802.1 priority tag value, and the last 5 bits are padded to 0. D_Layer3: 8 bits - This parameter is defined in section 5.29 of [RFC4710] and represents the layer 3 QoS marking used by the receiver to send packets to the data source during sub-session RC_N, if the Data Source can learn such information. Source Payload Type: 8 bits - This parameter is defined in section 5.24 of [RFC4710] and specifies the payload type of the data source of the communication sub-session RC_N as defined in [RFC3551]. Receiver Payload Type: 8 bits - This parameter is defined in section 5.25 of [RFC4710] and specifies the receiver payload type of the communication sub-session RC_N as defined in [RFC3551]. CPU Utilization: 8 bits - This parameter, defined in section 5.30 of [RFC4710], represents the percentage of CPU used during session RC_N from the last report until the time this RAQMON PDU was generated. The CPU Utilization is expressed in percents in the range 0 to 100. The value should indicate not only CPU utilization associated to a session RC_N but also actual CPU Utilization, to indicate a snapshot of the CPU utilization of the host running the RDS while session RC_N in progress. Memory Utilization: 8 bits - This parameter, defined in section 5.31 of [RFC4710], represents the percentage of total memory used during session RC_N up until the time this RAQMON PDU was generated. The memory utilization is expressed in percents 0 to 100. The Memory Utilization value should indicate not only the memory utilization associated to a session RC_N but the total memory utilization, to indicate a snapshot of end-device memory utilization while session RC_N is in progress. Session Setup Delay: 16 bits - The Session (sub-session) Setup Delay metric is defined in section 5.8 of [RFC4710] and expressed in milliseconds. Siddiqui, et al. Standards Track [Page 13]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Application Delay: 16 bits - The Application Delay is defined in section 5.13 of [RFC4710] and is represented as an unsigned integer expressed in milliseconds. IP Packet Delay Variation: 16 bits - The IP Packet Delay Variation is defined in section 5.15 of [RFC4710] and is represented as an unsigned integer expressed in milliseconds. Inter-Arrival Jitter: 16 bits - The Inter-Arrival Jitter is defined in section 5.14 of [RFC4710] and is represented as an unsigned integer expressed in milliseconds. Packet Discard in Fraction: 8 bits - This parameter is defined in section 5.23 of [RFC4710] and is expressed as a fixed-point number with the binary point at the left edge of the field. (That is equivalent to taking the integer part after multiplying the discard fraction by 256.) This metric is defined to be the number of packets discarded, divided by the total number of packets. Packet Loss in Fraction: 8 bits - This parameter is defined in section 5.21 of [RFC4710] and is expressed as a fixed-point number, with the binary point at the left edge of the field. The metric is defined to be the number of packets lost divided by the number of packets expected. The value is calculated by dividing the total number of packets lost (after the effects of applying any error protection, such as Forward Error Correction (FEC)) by the total number of packets expected, multiplying the result of the division by 256, limiting the maximum value to 255 (to avoid overflow), and taking the integer part. padding: 0, 8, 16, or 24 bits - If the padding bit (P) is set, then this field may be present. The actual padding at the end of the BASIC part of the PDU is 0, 8, 16, or 24 bits to make the length of the BASIC part of the PDU a multiple of 32 bits. 2.1.3. APP Part of the RAQMON Protocol Data Unit The APP part of the RAQMON PDU is intended to accommodate extensions for new applications in a modular manner and without requiring a PDU type value registration. Vendors may design and publish application-specific extensions. Any RAQMON-compliant RRC MUST be able to recognize vendors' SMI Enterprise Codes and MUST recognize the presence of application- specific extensions identified by using Report Type fields. As represented in Figure 1, the Report Type and Application Length Siddiqui, et al. Standards Track [Page 14]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 fields are always located at a fixed offset relative to the start of the extension fields. There is no need for the RRC to understand the semantics of the enterprise-specific parts of the PDU. SMI Enterprise Code: 32 bits - Vendors and application developers should fill in appropriate SMI Enterprise IDs available at http://www.iana.org/assignments/enterprise-numbers. A non-zero SMI Enterprise Code indicates a vendor- or application-specific extension. RAQMON PDUs are capable of carrying multiple Application Parts within a PDU. Report Type: 16 bits - Vendors and application developers should fill in the appropriate report type within a specified SMI Enterprise Code. It is RECOMMENDED that vendors publish application-specific extensions and maintain such report types for better interoperability. Length of the Application Part: 16 bits (unsigned integer) - The length of the Application Part of the RAQMON PDU in 32-bit words minus one, which includes the header of the Application Part. Application-dependent data: variable length - Application/ vendor-dependent data is defined by the application developers. It is interpreted by the vendor-specific application and not by the RRC itself. Its length must be a multiple of 32 bits and will be padded if necessary. 2.1.4. Byte Order, Alignment, and Time Format of RAQMON PDUs All integer fields are carried in network byte order, that is, most significant byte (octet) first. This byte order is commonly known as big-endian. The transmission order is described in detail in [RFC791]. Unless otherwise noted, numeric constants are in decimal (base 10). All header data is aligned to its natural length, i.e., 16-bit fields are aligned on even offsets, 32-bit fields are aligned at offsets divisible by four, etc. Octets designated as padding have the value zero. 2.2. Securing RAQMON Session The RAQMON session, initiated over TCP transport, between an RDS and an RRC carries monitoring information from an RDS client to the RRC, the collector. The RRC distinguishes between clients based on various identifiers used by the RDS to identify itself to the RRC Siddiqui, et al. Standards Track [Page 15]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 (Data Source Address and Data Source Name) and the RRC (Receiver's Address and Receiver's Name). In order to ensure integrity of the claimed identities of RDS and RRC to each other, authentication services are required. Subsequently, where protection from unauthorized modification and unauthorized disclosure of RAQMON data in transit from RDS to RRC is needed, data confidentiality and message integrity services will be required. In order to prevent monitoring-misinformation due to session-recording and replay by unauthorized sources, replay protection services may be required. TLS provides, at the transport layer, the required authentication services through the handshake protocol and subsequent data confidentiality, message integrity, and replay protection of the application protocol using a ciphersuite negotiated during authentication. The RDS client authenticates the RRC in session. The RRC optionally authenticates the RDS. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |PDT = 1 |B| T |P|S|R| RC | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DSRC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SMI Enterprise Code = 0 |Report Type = | RC_N | | | TLS_REQ| | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2: RAQMON StartTLS Request - TLS_REQ The protection of a RAQMON session starts with the RDS client's StartTLS request upon successful establishment of the TCP session. The RDS sends the StartTLS request by transmitting the TLS_REQ PDU as in Figure 2. This PDU is distinguished by TLS_REQ Report Type. Following this request, the client MUST NOT send any PDUs on this connection until it receives a StartTLS response. Other fields of the PDU are as specified in Figure 1. The flags field do not carry any significance and exist for compatibility with the generic RAQMON PDU. The flags field in this version MUST be ignored. Siddiqui, et al. Standards Track [Page 16]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 When a StartTLS request is made, the target server, RRC, MUST return a RAQMON PDU containing a StartTLS response, TLS_RESP. A RAQMON TLS_RESP is defined as follows: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |PDT = 1 |B| T |P|S|R| RC | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | DSRC | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | SMI Enterprise Code = 0 |Report Type = | Result | | | TLS_RESP| | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3: RAQMON StartTLS Response - TLS_RESP The RRC responds to the StartTLS request by transmitting the TLS_RESP PDU as in Figure 3. This PDU is distinguished by TLS_RESP Report Type. The Result field is an octet containing the result of the request. This field can carry one of the following values: +-------+------------------+----------------------------------------+ | Value | Mnemonic | Result | +-------+------------------+----------------------------------------+ | 0 | OK | Success. The server is willing and | | | | able to negotiate TLS. | | 1 | OP_ERR | Sequencing Error (e.g., TLS already | | | | established). | | 2 | PROTO_ERR | TLS not supported or incorrect PDU | | | | format. | | 3 | UNAVAIL | TLS service problem or RRC server | | | | going down. | | 4 | CONF_REQD | Confidentiality Service Required. | | | | | | 5 | STRONG_AUTH_REQD | Strong Authentication Service | | | | Required. | | 6 | REFERRAL | Referral to a RRC Server supporting | | | | TLS. | +-------+------------------+----------------------------------------+ Table 2 Other fields of the PDU are as specified in Figure 1. Siddiqui, et al. Standards Track [Page 17]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 The server MUST return OP_ERR if the client violates any of the StartTLS operation sequencing requirements described in the section below. If the server does not support TLS (whether by design or by current configuration), it MUST set the resultCode to PROTO_ERR or to REFERRAL. The server MUST include an actual referral value in the RAQMON REFER field if it returns a resultCode of referral. The client's current session is unaffected if the server does not support TLS. The client MAY proceed with RAQMON session, or it MAY close the connection. The server MUST return UNAVAIL if it supports TLS but cannot establish a TLS connection for some reason, e.g., if the certificate server not responding, if it cannot contact its TLS implementation, or if the server is in process of shutting down. The client MAY retry the StartTLS operation, MAY proceed with RAQMON session, or MAY close the connection. 2.2.1. Sequencing of the Start TLS Operation This section describes the overall procedures clients and servers MUST follow for TLS establishment. These procedures take into consideration various aspects of the overall security of the RAQMON connection including discovery of resulting security level. 2.2.1.1. Requesting to Start TLS on a RAQMON Association The client MAY send the StartTLS request at any time after establishing an RAQMON (TCP) connection, except that in the following cases the client MUST NOT send a StartTLS request: o if TLS is currently established on the connection, or o if RAQMON traffic is in progress on the connection. The result of violating any of these requirements is a Result of OP_ERR, as described above in Table 2. If the client did not establish a TLS connection before sending any other requests, and the server requires the client to establish a TLS connection before performing a particular request, the server MUST reject that request with a CONF_REQD or STRONG_AUTH_REQD result. The client MAY send a Start TLS extended request, or it MAY choose to close the connection. Siddiqui, et al. Standards Track [Page 18]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 2.2.1.2. Starting TLS The server will return an extended response with the resultCode of success if it is willing and able to negotiate TLS. It will return other resultCodes, documented above, if it is unable. In the successful case, the client, which has ceased to transfer RAQMON PDUs on the connection, MUST either begin a TLS negotiation or close the connection. The client will send PDUs in the TLS Record Protocol directly over the underlying transport connection to the server to initiate TLS negotiation [TLS]. 2.2.1.3. TLS Version Negotiation Negotiating the version of TLS or SSL to be used is a part of the TLS Handshake Protocol, as documented in [TLS]. The reader is referred to that document for details. 2.2.1.4. Discovery of Resultant Security Level After a TLS connection is established on a RAQMON connection, both parties MUST individually decide whether or not to continue based on the security assurance level achieved. Ascertaining the TLS connection's assurance level is implementation dependent and is accomplished by communicating with one's respective local TLS implementation. If the client or server decides that the level of authentication or confidentiality is not high enough for it to continue, it SHOULD gracefully close the TLS connection immediately after the TLS negotiation has completed Section 2.2.2.1. The client MAY attempt to Start TLS again, MAY disconnect, or MAY proceed to send RAQMON session data, if RRC policy permits. 2.2.1.5. Server Identity Check The client MUST check its understanding of the server's hostname against the server's identity as presented in the server's Certificate message, in order to prevent man-in-the-middle attacks. Matching is performed according to these rules: o The client MUST use the server dnsNAME in the subjectAltName field to validate the server certificate presented. The server dnsName MUST be part of subjectAltName of the server. o Matching is case-insensitive. Siddiqui, et al. Standards Track [Page 19]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 o The "*" wildcard character is allowed. If present, it applies only to the left-most name component. For example, *.example.com would match a.example.com, b.example.com, etc., but not example.com. If more than one identity of a given type is present in the certificate (e.g., more than one dNSName name), a match in any one of the set is considered acceptable. If the hostname does not match the dNSName-based identity in the certificate per the above check, automated clients SHOULD close the connection, returning and/or logging an error indicating that the server's identity is suspect. Beyond the server identity checks described in this section, clients SHOULD be prepared to do further checking to ensure that the server is authorized to provide the service it is observed to provide. The client MAY need to make use of local policy information. We also refer readers to similar guidelines as applied for LDAP over TLS [RFC4513]. 2.2.1.6. Client Identity Check Anonymous TLS authentication helps establish a TLS RAQMON session that offers o server-authentication in course of TLS establishment and o confidentiality and replay protection of RAQMON traffic, but o no protection against man-in-the-middle attacks during session establishment and o no protection from spoofing attacks by unauthorized clients. The server MUST authenticate the RDS client when deployment is susceptible to the above threats. This is done by requiring client authentication during TLS session establishment. In the TLS negotiation, the server MUST request a certificate. The client will provide its certificate to the server and MUST perform a private-key-based encryption, proving it has the private key associated with the certificate. As deployments will require protection of sensitive data in transit, the client and server MUST negotiate a ciphersuite that contains a bulk encryption algorithm of appropriate strength. Siddiqui, et al. Standards Track [Page 20]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 The server MUST verify that the client's certificate is valid. The server will normally check that the certificate is issued by a known CA, and that none of the certificates on the client's certificate chain are invalid or revoked. There are several procedures by which the server can perform these checks. The server validates the certificate by the Distinguished Name of the RDS client entity in the Subject field of the certificate. A corresponding set of guidelines will apply to use of TLS-PSK modes [TLS-PSK] using pre-shared keys instead of client certificates. 2.2.1.7. Refresh of Server Capabilities Information The client MUST refresh any cached server capabilities information upon TLS session establishment, such as prior RRC state related to a previous RAQMON session based on another DSRC. This is necessary to protect against active-intermediary attacks, which may have altered any server capabilities information retrieved prior to TLS establishment. The server MAY advertise different capabilities after TLS establishment. 2.2.2. Closing a TLS Connection 2.2.2.1. Graceful Closure Either the client or server MAY terminate the TLS connection on an RAQMON session by sending a TLS closure alert. This will leave the RAQMON connection intact. Before closing a TLS connection, the client MUST wait for any outstanding RAQMON transmissions to complete. This happens naturally when the RAQMON client is single-threaded and synchronous. After the initiator of a close has sent a closure alert, it MUST discard any TLS messages until it has received an alert from the other party. It will cease to send TLS Record Protocol PDUs and, following the receipt of the alert, MAY send and receive RAQMON PDUs. The other party, if it receives a closure alert, MUST immediately transmit a TLS closure alert. It will subsequently cease to send TLS Record Protocol PDUs and MAY send and receive RAQMON PDUs. Siddiqui, et al. Standards Track [Page 21]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 2.2.2.2. Abrupt Closure Either the client or server MAY abruptly close the entire RAQMON session and any TLS connection established on it by dropping the underlying TCP connection. It MAY be possible for RRC to send RDS a disconnection notification, which allows the client to know that the disconnection is not due to network failure. However, this message is not defined in this version. 2.3. SNMP Notifications as an RDS/RRC Network Transport Protocol It was an inherent objective of the RAQMON Framework to re-use existing application-level transport protocols to maximize the usage of existing installations as well as to avoid transport-protocol- level complexities in the design process. Choice of SNMP as a means to transport RAQMON PDU was motivated by the intent of using existing installed devices implementing SNMP agents as RAQMON Data Sources (RDSs). There are some potential problems with the usage of SNMP as a transport mapping protocol: o The potential of congestion is higher than with the TCP transport, because of the usage of UDP at the transport layer. o The encoding of the information is less efficient, and this results in bigger message size, which again may negatively impact congestion conditions and memory size requirements in the devices. In order to avoid these potential problems, the following recommendations are made: o Usage of the TCP transport is RECOMMENDED in deployment over the SNMP transport wherever available for a pair of RDS/RRC. o The usage of Inform PDUs is RECOMMENDED. o The usage of Traps PDU is NOT RECOMMENDED. o It is RECOMMENDED that information carried by notifications be maintained within the limits of the MTU size in order to avoid fragmentation. If SNMP is chosen as a mechanism to transport RAQMON PDUs, the following specification applies to RAQMON-related usage of SNMP: Siddiqui, et al. Standards Track [Page 22]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 o RDSs implement the capability of embedding RAQMON parameters in SNMP Notifications, re-using well-known SNMP mechanisms to report RAQMON Statistics. The RAQMON RDS MIB module, as specified in 2.1.1, MUST be used in order to map the RAQMON PDUs onto the SNMP Notifications transport. o Since RDSs are not computationally rich, and in order to keep the RDS realization as lightweight as possible, RDSs MAY fail to respond to SNMP requests like GET, SET, etc., with the exception of the GET and SET commands required to implement the User-Based Security Model (USM) defined by [RFC3414]. o In order to meet congestion safety requirements, SNMP INFORM PDUs SHOULD be used. In case INFORM PDUs are used, RDSs MUST process the SNMP INFORM responses from RRCs and MUST serialize the PDU transmission rate, i.e., limit the number of PDUS sent in a specific time interval. o Standard UDP port 162 SHOULD be used for SNMP Notifications. 2.3.1. Encoding RAQMON Using the RAQMON RDS MIB Module The RAQMON RDS MIB module is used to map RAQMON PDUs onto SNMP Notifications for transport purposes. The MIB module defines the objects needed for mapping the BASIC part of RAQMON PDU, defined in [RFC4710], as well as the Notifications themselves. In order to incorporate any application-specific extensions in the Application (APP) part of RAQMON PDU, as defined in [RFC4710], additional variable bindings MAY be included in RAQMON notifications as described in the MIB module. For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of [RFC3410]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP). Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, [RFC2578], STD 58, [RFC2579] and STD 58, [RFC2580]. Siddiqui, et al. Standards Track [Page 23]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 The following MIB module IMPORTS definitions from the following: SNMPv2-SMI [RFC2578] SNMPv2-TC [RFC2579] SNMPv2-CONF [RFC2580] RMON-MIB [RFC2819] DIFFSERV-DSCP-TC [RFC3289] SNMP-FRAMEWORK-MIB [RFC3411] INET-ADDRESS-MIB [RFC4001] It also uses REFERENCE clauses to refer to [RFC4710]. RAQMON-RDS-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, Counter32, Unsigned32 FROM SNMPv2-SMI DateAndTime FROM SNMPv2-TC rmon FROM RMON-MIB SnmpAdminString FROM SNMP-FRAMEWORK-MIB InetAddressType, InetAddress, InetPortNumber FROM INET-ADDRESS-MIB Dscp FROM DIFFSERV-DSCP-TC MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP FROM SNMPv2-CONF; raqmonDsMIB MODULE-IDENTITY LAST-UPDATED "200610100000Z" -- October 10, 2006 ORGANIZATION "RMON Working Group" CONTACT-INFO "WG EMail: rmonmib@ietf.org Subscribe: rmonmib-request@ietf.org MIB Editor: Eugene Golovinsky Postal: BMC Software, Inc. 2101 CityWest Boulevard, Siddiqui, et al. Standards Track [Page 24]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Houston, TX, 77094 USA Tel: +713-918-1816 Email: egolovin@bmc.com " DESCRIPTION "This is the RAQMON Data Source notification MIB Module. It provides a mapping of RAQMON PDUs to SNMP notifications. Ds stands for data source. Note that all of the object types defined in this module are accessible-for-notify and would consequently not be available to a browser using simple Get, GetNext, or GetBulk requests. Copyright (c) The Internet Society (2006). This version of this MIB module is part of RFC 4712; See the RFC itself for full legal notices." REVISION "200610100000Z" -- October 10, 2006 DESCRIPTION "Initial version, published as RFC 4712." ::= { rmon 32 } -- This OID allocation conforms to [RFC3737] raqmonDsNotifications OBJECT IDENTIFIER ::= { raqmonDsMIB 0 } raqmonDsMIBObjects OBJECT IDENTIFIER ::= { raqmonDsMIB 1 } raqmonDsConformance OBJECT IDENTIFIER ::= { raqmonDsMIB 2 } raqmonDsNotificationTable OBJECT-TYPE SYNTAX SEQUENCE OF RaqmonDsNotificationEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "This conceptual table provides the SNMP mapping of the RAQMON BASIC PDU. It is indexed by the RAQMON Data Source, sub-session, and address of the peer entity. Note that there is no concern about the indexation of this table exceeding the limits defined by RFC 2578 Section 3.5. According to [RFC4710], Section 5.1, Siddiqui, et al. Standards Track [Page 25]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 only IPv4 and IPv6 addresses can be reported as participant addresses." ::= { raqmonDsMIBObjects 1 } raqmonDsNotificationEntry OBJECT-TYPE SYNTAX RaqmonDsNotificationEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "The entry (row) is not retrievable and is not kept by RDSs. It serves data organization purposes only." INDEX { raqmonDsDSRC, raqmonDsRCN, raqmonDsPeerAddrType, raqmonDsPeerAddr } ::= { raqmonDsNotificationTable 1 } RaqmonDsNotificationEntry ::= SEQUENCE { raqmonDsDSRC Unsigned32, raqmonDsRCN Unsigned32, raqmonDsPeerAddrType InetAddressType, raqmonDsPeerAddr InetAddress, raqmonDsAppName SnmpAdminString, raqmonDsDataSourceDevicePort InetPortNumber, raqmonDsReceiverDevicePort InetPortNumber, raqmonDsSessionSetupDateTime DateAndTime, raqmonDsSessionSetupDelay Unsigned32, raqmonDsSessionDuration Unsigned32, raqmonDsSessionSetupStatus SnmpAdminString, raqmonDsRoundTripEndToEndNetDelay Unsigned32, raqmonDsOneWayEndToEndNetDelay Unsigned32, raqmonDsApplicationDelay Unsigned32, raqmonDsInterArrivalJitter Unsigned32, raqmonDsIPPacketDelayVariation Unsigned32, raqmonDsTotalPacketsReceived Counter32, raqmonDsTotalPacketsSent Counter32, raqmonDsTotalOctetsReceived Counter32, raqmonDsTotalOctetsSent Counter32, raqmonDsCumulativePacketLoss Counter32, raqmonDsPacketLossFraction Unsigned32, raqmonDsCumulativeDiscards Counter32, raqmonDsDiscardsFraction Unsigned32, raqmonDsSourcePayloadType Unsigned32, raqmonDsReceiverPayloadType Unsigned32, raqmonDsSourceLayer2Priority Unsigned32, raqmonDsSourceDscp Dscp, raqmonDsDestinationLayer2Priority Unsigned32, raqmonDsDestinationDscp Dscp, raqmonDsCpuUtilization Unsigned32, raqmonDsMemoryUtilization Unsigned32 } Siddiqui, et al. Standards Track [Page 26]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 raqmonDsDSRC OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS not-accessible STATUS current DESCRIPTION "Data Source identifier represents a unique session descriptor that points to a specific session between communicating entities. Identifiers unique for sessions conducted between two entities are generated by the communicating entities. Zero is a valid value, with no special semantics." ::= { raqmonDsNotificationEntry 1 } raqmonDsRCN OBJECT-TYPE SYNTAX Unsigned32 (0..15) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The Record Count Number indicates a sub-session within a communication session. A maximum number of 16 sub-sessions are supported; this limitation is dictated by reasons of compatibility with other transport protocols." ::= { raqmonDsNotificationEntry 2 } raqmonDsPeerAddrType OBJECT-TYPE SYNTAX InetAddressType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The type of the Internet address of the peer participant for this session." REFERENCE "Section 5.2 of [RFC4710]" ::= { raqmonDsNotificationEntry 3 } raqmonDsPeerAddr OBJECT-TYPE SYNTAX InetAddress MAX-ACCESS not-accessible STATUS current DESCRIPTION "The Internet Address of the peer participant for this session." REFERENCE "Section 5.2 of [RFC4710]" ::= { raqmonDsNotificationEntry 4 } raqmonDsAppName OBJECT-TYPE Siddiqui, et al. Standards Track [Page 27]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 SYNTAX SnmpAdminString MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "This is a text string giving the name and possibly the version of the application associated with that session, e.g., 'XYZ VoIP Agent 1.2'." REFERENCE "Section 5.28 of [RFC4710]" ::= { raqmonDsNotificationEntry 5 } raqmonDsDataSourceDevicePort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The port number from which data for this session was sent by the Data Source device." REFERENCE "Section 5.5 of [RFC4710]" ::= { raqmonDsNotificationEntry 6 } raqmonDsReceiverDevicePort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The port number where the data for this session was received." REFERENCE "Section 5.6 of [RFC4710]" ::= { raqmonDsNotificationEntry 7 } raqmonDsSessionSetupDateTime OBJECT-TYPE SYNTAX DateAndTime MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The time when session was initiated." REFERENCE "Section 5.7 of [RFC4710]" ::= { raqmonDsNotificationEntry 8 } raqmonDsSessionSetupDelay OBJECT-TYPE SYNTAX Unsigned32 (0..65535) UNITS "milliseconds" MAX-ACCESS accessible-for-notify STATUS current Siddiqui, et al. Standards Track [Page 28]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 DESCRIPTION "Session setup time." REFERENCE "Section 5.8 of [RFC4710]" ::= { raqmonDsNotificationEntry 9 } raqmonDsSessionDuration OBJECT-TYPE SYNTAX Unsigned32 UNITS "seconds" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Session duration, including setup time. The SYNTAX of this object allows expression of the duration of sessions that do not exceed 4660 hours and 20 minutes." REFERENCE "Section 5.9 of [RFC4710]" ::= { raqmonDsNotificationEntry 10 } raqmonDsSessionSetupStatus OBJECT-TYPE SYNTAX SnmpAdminString MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Describes appropriate communication session states, e.g., Call Established successfully, RSVP reservation failed, etc." REFERENCE "Section 5.10 of [RFC4710]" ::= { raqmonDsNotificationEntry 11 } raqmonDsRoundTripEndToEndNetDelay OBJECT-TYPE SYNTAX Unsigned32 UNITS "milliseconds" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Most recent available information about the round-trip end-to-end network delay." REFERENCE "Section 5.11 of [RFC4710]" ::= { raqmonDsNotificationEntry 12} raqmonDsOneWayEndToEndNetDelay OBJECT-TYPE SYNTAX Unsigned32 UNITS "milliseconds" MAX-ACCESS accessible-for-notify STATUS current Siddiqui, et al. Standards Track [Page 29]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 DESCRIPTION "Most recent available information about the one-way end-to-end network delay." REFERENCE "Section 5.12 of [RFC4710]" ::= { raqmonDsNotificationEntry 13} raqmonDsApplicationDelay OBJECT-TYPE SYNTAX Unsigned32 (0..65535) UNITS "milliseconds" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Most recent available information about the application delay." REFERENCE "Section 5.13 of [RFC4710" ::= { raqmonDsNotificationEntry 14} raqmonDsInterArrivalJitter OBJECT-TYPE SYNTAX Unsigned32 (0..65535) UNITS "milliseconds" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "An estimate of the inter-arrival jitter." REFERENCE "Section 5.14 of [RFC4710]" ::= { raqmonDsNotificationEntry 15} raqmonDsIPPacketDelayVariation OBJECT-TYPE SYNTAX Unsigned32 (0..65535) UNITS "milliseconds" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "An estimate of the inter-arrival delay variation." REFERENCE "Section 5.15 of [RFC4710]" ::= { raqmonDsNotificationEntry 16} raqmonDsTotalPacketsReceived OBJECT-TYPE SYNTAX Counter32 UNITS "packets" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The number of packets transmitted within a communication Siddiqui, et al. Standards Track [Page 30]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 session by the receiver since the start of the session." REFERENCE "Section 5.16 of [RFC4710]" ::= { raqmonDsNotificationEntry 17 } raqmonDsTotalPacketsSent OBJECT-TYPE SYNTAX Counter32 UNITS "packets" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The number of packets transmitted within a communication session by the sender since the start of the session." REFERENCE "Section 5.17 of [RFC4710]" ::= { raqmonDsNotificationEntry 18 } raqmonDsTotalOctetsReceived OBJECT-TYPE SYNTAX Counter32 UNITS "octets" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The total number of payload octets (i.e., not including header or padding octets) transmitted in packets by the receiver within a communication session since the start of the session." REFERENCE "Section 5.18 of [RFC4710]" ::= { raqmonDsNotificationEntry 19 } raqmonDsTotalOctetsSent OBJECT-TYPE SYNTAX Counter32 UNITS "octets" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The number of payload octets (i.e., not including headers or padding) transmitted in packets by the sender within a communication sub-session since the start of the session." REFERENCE "Section 5.19 of [RFC4710]" ::= { raqmonDsNotificationEntry 20 } raqmonDsCumulativePacketLoss OBJECT-TYPE SYNTAX Counter32 UNITS "packets" Siddiqui, et al. Standards Track [Page 31]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The number of packets from this session whose loss had been detected since the start of the session." REFERENCE "Section 5.20 of [RFC4710]" ::= { raqmonDsNotificationEntry 21 } raqmonDsPacketLossFraction OBJECT-TYPE SYNTAX Unsigned32 (0..100) UNITS "percentage of packets sent" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The percentage of lost packets with respect to the overall packets sent. This is defined to be 100 times the number of packets lost divided by the number of packets expected." REFERENCE "Section 5.21 of [RFC4710]" ::= { raqmonDsNotificationEntry 22 } raqmonDsCumulativeDiscards OBJECT-TYPE SYNTAX Counter32 UNITS "packets" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The number of packet discards detected since the start of the session." REFERENCE "Section 5.22 of [RFC4710]" ::= { raqmonDsNotificationEntry 23 } raqmonDsDiscardsFraction OBJECT-TYPE SYNTAX Unsigned32 (0..100) UNITS "percentage of packets sent" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The percentage of discards with respect to the overall packets sent. This is defined to be 100 times the number of discards divided by the number of packets expected." REFERENCE "Section 5.23 of [RFC4710]" ::= { raqmonDsNotificationEntry 24 } Siddiqui, et al. Standards Track [Page 32]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 raqmonDsSourcePayloadType OBJECT-TYPE SYNTAX Unsigned32 (0..127) MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The payload type of the packet sent by this RDS." REFERENCE "RFC 1890, Section 5.24 of [RFC4710] " ::= { raqmonDsNotificationEntry 25 } raqmonDsReceiverPayloadType OBJECT-TYPE SYNTAX Unsigned32 (0..127) MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "The payload type of the packet received by this RDS." REFERENCE "RFC 1890, Section 5.25 of [RFC4710] " ::= { raqmonDsNotificationEntry 26 } raqmonDsSourceLayer2Priority OBJECT-TYPE SYNTAX Unsigned32 (0..7) MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Source Layer 2 priority used by the data source to send packets to the receiver by this data source during this communication session." REFERENCE "Section 5.26 of [RFC4710]" ::= { raqmonDsNotificationEntry 27 } raqmonDsSourceDscp OBJECT-TYPE SYNTAX Dscp MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Layer 3 TOS/DSCP values used by the Data Source to prioritize traffic sent." REFERENCE "Section 5.27 of [RFC4710]" ::= { raqmonDsNotificationEntry 28 } raqmonDsDestinationLayer2Priority OBJECT-TYPE SYNTAX Unsigned32 (0..7) MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION Siddiqui, et al. Standards Track [Page 33]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 "Destination Layer 2 priority. This is the priority used by the peer communicating entity to send packets to the data source." REFERENCE "Section 5.28 of [RFC4710]" ::= { raqmonDsNotificationEntry 29 } raqmonDsDestinationDscp OBJECT-TYPE SYNTAX Dscp MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Layer 3 TOS/DSCP values used by the peer communicating entity to prioritize traffic sent to the source." REFERENCE "Section 5.29 of [RFC4710]" ::= { raqmonDsNotificationEntry 30 } raqmonDsCpuUtilization OBJECT-TYPE SYNTAX Unsigned32 (0..100) UNITS "percent" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Latest available information about the total CPU utilization." REFERENCE "Section 5.30 of [RFC4710]" ::= { raqmonDsNotificationEntry 31 } raqmonDsMemoryUtilization OBJECT-TYPE SYNTAX Unsigned32 (0..100) UNITS "percent" MAX-ACCESS accessible-for-notify STATUS current DESCRIPTION "Latest available information about the total memory utilization." REFERENCE "Section 5.31 of [RFC4710]" ::= { raqmonDsNotificationEntry 32 } -- definitions of the notifications -- -- raqmonDsAppName is the only object that MUST be sent by an -- RDS every time the static notification is generated. Siddiqui, et al. Standards Track [Page 34]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 -- raqmonDsTotalPacketsReceived is the only object that MUST be -- sent by an RD every time the dynamic notification is generated. -- Other objects from the raqmonDsNotificationTable may be -- included in the variable binding list. Specifically, a raqmon -- notification will include MIB objects that provide information -- about metrics that characterize the application session raqmonDsStaticNotification NOTIFICATION-TYPE OBJECTS { raqmonDsAppName } STATUS current DESCRIPTION "This notification maps the static parameters in the BASIC RAQMON PDU onto an SNMP transport. This notification is expected to be sent once per session, or when a new sub-session is initiated. The following objects MAY be carried by the raqmonDsStaticNotification: raqmonDsDataSourceDevicePort, raqmonDsReceiverDevicePort, raqmonDsSessionSetupDateTime, raqmonDsSessionSetupDelay, raqmonDsSessionDuration, raqmonDsSourcePayloadType, raqmonDsReceiverPayloadType, raqmonDsSourceLayer2Priority, raqmonDsSourceDscp, raqmonDsDestinationLayer2Priority, raqmonDsDestinationDscp It is RECOMMENDED to keep the size of a notification within the MTU size limits in order to avoid fragmentation." ::= { raqmonDsNotifications 1 } raqmonDsDynamicNotification NOTIFICATION-TYPE OBJECTS { raqmonDsTotalPacketsReceived } STATUS current DESCRIPTION "This notification maps the dynamic parameters in the BASIC RAQMON PDU onto an SNMP transport. The following objects MAY be carried by the raqmonDsDynamicNotification: raqmonDsRoundTripEndToEndNetDelay, raqmonDsOneWayEndToEndNetDelay, Siddiqui, et al. Standards Track [Page 35]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 raqmonDsApplicationDelay, raqmonDsInterArrivalJitter, raqmonDsIPPacketDelayVariation, raqmonDsTotalPacketsSent, raqmonDsTotalOctetsReceived, raqmonDsTotalOctetsSent, raqmonDsCumulativePacketLoss, raqmonDsPacketLossFraction, raqmonDsCumulativeDiscards, raqmonDsDiscardsFraction, raqmonDsCpuUtilization, raqmonDsMemoryUtilization It is RECOMMENDED to keep the size of a notification within the MTU size limits in order to avoid fragmentation." ::= { raqmonDsNotifications 2 } raqmonDsByeNotification NOTIFICATION-TYPE OBJECTS { raqmonDsAppName } STATUS current DESCRIPTION "The BYE Notification. This Notification is the equivalent of the RAQMON NULL PDU, which signals the end of a RAQMON session." ::= { raqmonDsNotifications 3 } -- -- conformance information raqmonDsCompliance OBJECT IDENTIFIER ::= { raqmonDsConformance 1 } raqmonDsGroups OBJECT IDENTIFIER ::= { raqmonDsConformance 2 } raqmonDsBasicCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for SNMP entities that implement this MIB module. There are a number of INDEX objects that cannot be represented in the form of OBJECT clauses in SMIv2, but for which we have the following compliance requirements, expressed in OBJECT clause form in this description clause: -- OBJECT raqmonDsPeerAddrType -- SYNTAX InetAddressType { ipv4(1), ipv6(2) } Siddiqui, et al. Standards Track [Page 36]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 -- DESCRIPTION -- This MIB requires support for only global IPv4 -- and IPv6 address types. -- -- OBJECT raqmonDsPeerAddr -- SYNTAX InetAddress (SIZE(4|16)) -- DESCRIPTION -- This MIB requires support for only global IPv4 -- and IPv6 address types. -- " MODULE -- this module MANDATORY-GROUPS { raqmonDsNotificationGroup, raqmonDsPayloadGroup } ::= { raqmonDsCompliance 1 } raqmonDsNotificationGroup NOTIFICATION-GROUP NOTIFICATIONS { raqmonDsStaticNotification, raqmonDsDynamicNotification, raqmonDsByeNotification } STATUS current DESCRIPTION "Standard RAQMON Data Source Notification group." ::= { raqmonDsGroups 1 } raqmonDsPayloadGroup OBJECT-GROUP OBJECTS { raqmonDsAppName, raqmonDsDataSourceDevicePort, raqmonDsReceiverDevicePort, raqmonDsSessionSetupDateTime, raqmonDsSessionSetupDelay, raqmonDsSessionDuration, raqmonDsSessionSetupStatus, raqmonDsRoundTripEndToEndNetDelay, raqmonDsOneWayEndToEndNetDelay, raqmonDsApplicationDelay, raqmonDsInterArrivalJitter, raqmonDsIPPacketDelayVariation, raqmonDsTotalPacketsReceived, raqmonDsTotalPacketsSent, raqmonDsTotalOctetsReceived, raqmonDsTotalOctetsSent, raqmonDsCumulativePacketLoss, raqmonDsPacketLossFraction, raqmonDsCumulativeDiscards, raqmonDsDiscardsFraction, raqmonDsSourcePayloadType, raqmonDsReceiverPayloadType, Siddiqui, et al. Standards Track [Page 37]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 raqmonDsSourceLayer2Priority, raqmonDsSourceDscp, raqmonDsDestinationLayer2Priority, raqmonDsDestinationDscp, raqmonDsCpuUtilization, raqmonDsMemoryUtilization } STATUS current DESCRIPTION "Standard RAQMON Data Source payload MIB objects group." ::= { raqmonDsGroups 2 } END 3. IANA Considerations Applications using the RAQMON Framework require a single fixed port. Port number 7744 is registered with IANA for use as the default port for RAQMON PDUs over TCP. Hosts that run multiple applications may use this port as an indication to have used RAQMON or provision a separate TCP port as part of provisioning RAQMON RDS and RAQMON Collector. The particular port number was chosen to lie in the range above 5000 to accommodate port number allocation practice within the Unix operating system, where privileged processes can only use port numbers below 1024 and port numbers between 1024 and 5000 are automatically assigned by the operating systems. The OID assignment for the raqmonDsMIB MODULE-IDENTITY is made according to [RFC3737], and there is no need for any IANA action on this respect. 4. Congestion-Safe RAQMON Operation As outlined in earlier sections, the TCP congestion control mechanism provides inherent congestion safety features when TCP is implemented as transport to carry RAQMON PDU. To ensure congestion safety, clearly the best thing to do is to use a congestion-safe transport protocol such as TCP. If this is not feasible, it may be necessary to fall back to UDP since SNMP over UDP is a widely deployed transport protocol. When SNMP is chosen as RAQMON PDU Transport, implementers MUST follow section 3 of [RFC4710], which outlines measures that MUST be taken to use RAQMON in a congestion-safe manner. Congestion safety Siddiqui, et al. Standards Track [Page 38]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 requirements in section 3 of [RFC4710] would ensure that a RAQMON implementation using SNMP over UDP does not lead to congestion under heavy network load. 5. Acknowledgements The authors would like to thank Bill Walker and Joseph Mastroguilio from Avaya and Bin Hu from Motorola for their discussions. The authors would also like to extend special thanks to Randy Presuhn, who reviewed this document for spelling and formatting purposes, and who provided a deep review of the technical content. We also would like to thank Bert Wijnen for the permanent coaching during the evolution of this document and the detailed review of its final versions. The Security Considerations section was reviewed by Sam Hartman and Kurt D. Zeilenga and almost completely re-written by Mahalingam Mani. 6. Security Considerations [RFC4710] outlines a threat model associated with RAQMON and security considerations to be taken into account in the RAQMON specification to mitigate against those threats. It is imperative that RAQMON PDU implementations be able to provide the following protection mechanisms in order to attain end-to-end security: 1. Authentication: The RRC SHOULD be able to verify that a RAQMON report was originated by the RDS claiming to have sent it. At minimum, an RDS/RRC pair MUST use a digest-based authentication procedure to authenticate, like the one defined in [RFC1321]. 2. Privacy: RAQMON information includes identification of the parties participating in a communication session. RAQMON deployments SHOULD be able to provide protection from eavesdropping, and to prevent an unauthorized third party from gathering potentially sensitive information. This can be achieved by using secure transport protocols supporting confidentiality based on encryption technologies such as DES (Data Encryption Standard), [3DES], and AES (Advanced Encryption Standard) [AES]. 3. Protection from DoS attacks directed at the RRC: RDSs send RAQMON reports as a side effect of external events (for example, receipt of a phone call). An attacker can try to overwhelm the RRC (or the network) by initiating a large number of events in order to swamp the RRC with excessive numbers of RAQMON PDUs. Siddiqui, et al. Standards Track [Page 39]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 To prevent DoS attacks against the RRC, the RDS will send the first report for a session only after the session has been established, so that the session set-up process is not affected. 4. NAT and Firewall Friendly Design: The presence of IP addresses and TCP/UDP port information in RAQMON PDUs may be NAT- unfriendly. Where NAT-friendliness is a requirement, the RDS MAY omit IP address information from the RAQMON PDU. Another way to avoid this problem is by using NAT-Aware Application Layer Gateways (ALGs) to ensure that correct IP addresses appear in RAQMON PDUs. For the usage of TCP, TLS MUST be used to provide transport layer security. Section 6.1 describes the usage of TLS with RAQMON. This memo also defines the RAQMON-RDS-MIB module with the purpose of mapping the RAQMON PDUs into SNMP Notifications. To attain end-to- end security, the following measures have been taken in the RAQMON- RDS-MIB module design: There are no management objects defined in this MIB module that have a MAX-ACCESS clause of read-write and/or read-create. Consequently, if this MIB module is implemented correctly, there is no risk that an intruder can alter or create any management objects of this MIB module via direct SNMP SET operations. Some of the readable objects in this MIB module (i.e., objects with a MAX-ACCESS other than not-accessible) may be considered sensitive or vulnerable in some network environments. It is thus important to control even GET and/or NOTIFY access to these objects and possibly to even encrypt the values of these objects when sending them over the network via SNMP. These are the tables and objects and their sensitivity/vulnerability: raqmonDsNotificationTable The objects in this table contain user session information, and their disclosure may be sensitive in some environments. SNMP versions prior to SNMPv3 did not include adequate security. Even if the network itself is secure (for example by using IPsec), even then, there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB module. Siddiqui, et al. Standards Track [Page 40]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 It is RECOMMENDED that implementers consider the security features as provided by the SNMPv3 framework (see [RFC3410], section 8), including full support for the SNMPv3 cryptographic mechanisms (for authentication and confidentiality). It is a customer/operator responsibility to ensure that the SNMP entity giving access to an instance of this MIB module is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them. 6.1. Usage of TLS with RAQMON 6.1.1. Confidentiality & Message Integrity The subsequently authorized RAQMON data flow itself is protected by the same TLS security association that protects the client-side exchange. This standard TLS channel is now bound to the server through the above client-side authentication. The session itself is identified by the tuple {RDS ip-address:RDS_port / RRC ip-address: RRC port}. 6.1.2. TLS CipherSuites Several issues should be considered when selecting TLS ciphersuites that are appropriate for use in a given circumstance. These issues include the following: The ciphersuite's ability to provide adequate confidentiality protection for passwords and other data sent over the transport connection. Client and server implementers should recognize that some TLS ciphersuites provide no confidentiality protection, while other ciphersuites that do provide confidentiality protection may be vulnerable to being cracked using brute force methods, especially in light of ever-increasing CPU speeds that reduce the time needed to successfully mount such attacks. Client and server implementers should carefully consider the value of the password or data being protected versus the level of confidentiality protection provided by the ciphersuite to ensure that the level of protection afforded by the ciphersuite is appropriate. The ciphersuite's vulnerability (or lack thereof) to man-in-the- middle attacks. Ciphersuites vulnerable to man-in-the-middle attacks SHOULD NOT be used to protect passwords or sensitive data, unless the network configuration is such that the danger of a man-in-the-middle attack is negligible. Siddiqui, et al. Standards Track [Page 41]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 After a TLS negotiation (either initial or subsequent) is completed, both protocol peers should independently verify that the security services provided by the negotiated ciphersuite are adequate for the intended use of the RAQMON session. If not, the TLS layer should be closed. Spoofing Attacks: When anonymous TLS alone is negotiated without client authentication, the client's identity is never established. This easily allows any end-entity to establish a TLS-secured RAQMON connection to the RRC. This not only offers an opportunity to spoof legitimate RDS clients and hence compromise the integrity of RRC monitoring data, but also opens the RRC up to unauthorized clients posing as genuine RDS entities to launch a DoS by flooding data. RAQMON deployment policy MUST consider requiring RDS client authentication during TLS session establishment, especially when RDS clients communicate across unprotected internet. Insider attacks: Even client-authenticated TLS connections are open to spoofing attacks by one trusted client on another. Validation of RDS source address against RDS TLS-session source address SHOULD be performed to detect such attempts. 6.1.3. RAQMON Authorization State Every RAQMON session (between RDS and RRC) has an associated authorization state. This state is comprised of numerous factors such as what (if any) authorization state has been established, how it was established, and what security services are in place. Some factors may be determined and/or affected by protocol events (e.g., StartTLS, or TLS closure), and some factors may be determined by external events (e.g., time of day or server load). While it is often convenient to view authorization state in simplistic terms (as we often do in this technical specification) such as "an anonymous state", it is noted that authorization systems in RAQMON implementations commonly involve many factors that interrelate. Authorization in RAQMON is a local matter. One of the key factors in making authorization decisions is authorization identity. The initial session establishment defined in Section 2.2 allows information to be exchanged between the client and server to establish an authorization identity for the RAQMON session. The RRC is not to allow any RDS-transactions-related traffic through for processing until the client authentication is complete, unless anonymous authentication mode is negotiated. Siddiqui, et al. Standards Track [Page 42]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Upon initial establishment of the RAQMON session, the session has an anonymous authorization identity. Among other things, this implies that the client need not send a TLSStartRequired in the first PDU of the RAQMON message. The client may send any operation request prior to binding RDS to any authentication, and the RRC MUST treat it as if it had been performed after an anonymous RAQMON session start. The RDS automatically is placed in an unauthorized state upon RRC sending a TLSstart request to the RRC. It is noted that other events both internal and external to RAQMON may result in the authentication and authorization states being moved to an anonymous one. For instance, the establishment, change, or closure of data security services may result in a move to an anonymous state, or the user's credential information (e.g., certificate) may have expired. The former is an example of an event internal to RAQMON, whereas the latter is an example of an event external to RAQMON. 7. References 7.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [RFC2819] Waldbusser, S., "Remote Network Monitoring Management Information Base", STD 59, RFC 2819, May 2000. [RFC3289] Baker, F., Chan, K., and A. Smith, "Management Information Base for the Differentiated Services Architecture", RFC 3289, May 2002. Siddiqui, et al. Standards Track [Page 43]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 [RFC3411] Harrington, D., Preshun, R., and B. Wijnen, "An Architecture for Describing Simple Network Management Protocol (SNMP) Management Frameworks", STD 62, RFC 3411, December 2002. [RFC4001] Daniele, M., Haberman, B., Routhier, S., and J. Schoenwalder, "Textual Conventions for Internet Network Addresses", RFC 4001, February 2005. [RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791, September 1981. [RFC793] Postel, J., "Transmission Control Protocol", STD 7, RFC 793, September 1981. [RFC4710] Siddiqui, A., Romascanu, D., and E. Golovinsky, "Real- time Application Quality-of-Service Monitoring (RAQMON)", RFC 4710, October 2006. [TLS] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.1", RFC 4346, April 2006. 7.2. Informative References [3DES] Americation National Standards Institute, "Triple Data Encryption Algorithm Modes of Operation", ANSI X9.52-1998. [AES] Federal Information Processing Standard (FIPS), "Specifications for the ADVANCED ENCRYPTION STANDARD(AES)", Publication 197, November 2001. [IEEE802.1D] "Information technology-Telecommunications and information exchange between systems--Local and metropolitan area networks-Common Specification a--Media access control (MAC) bridges:15802-3: 1998(ISO/IEC)", [ANSI/IEEE Std 802.1D Edition], 1998. [RFC1305] Mills, D., "Network Time Protocol Version 3", RFC 1305, March 1992. [RFC1321] Rivest, R., "Message Digest Algorithm MD5", RFC 1321, April 1992. Siddiqui, et al. Standards Track [Page 44]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 [RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction and Applicability Statements for Internet-Standard Management Framework", RFC 3410, December 2002. [RFC3414] Blumenthal, U. and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 3414, December 2002. [RFC3550] Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications", RFC 3550, July 2003. [RFC3551] Schulzrinne, H. and S. Casner, "RTP Profile for Audio and Video Conferences with Minimal Control", STD 65, RFC 3551, July 2003. [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD 63, RFC 3629, November 2003. [RFC3737] Wijnen, B. and A. Bierman, "IANA Guidelines for the Registry of Remote Monitoring (RMON) MIB modules", RFC 3737, April 2004. [RFC4513] Harrison, R., "Lightweight Directory Access Protocol (LDAP): Authentication Methods and Security Mechanisms", RFC 4513, June 2006. [TLS-PSK] Eronen, P. and H. Tschofenig, "Pre-Shared Key Ciphersuites for Transport Layer Security (TLS)", RFC 4279, December 2005. Siddiqui, et al. Standards Track [Page 45]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Appendix A. Pseudocode The implementation notes included in Appendix are for informational purposes only and are meant to clarify the RAQMON specification. Pseudocode for RDS & RRC We provide examples of pseudocode for aspects of RDS and RRC. There may be other implementation methods that are faster in particular operating environments or have other advantages. RDS: when (session starts} { report.identifier = session.endpoints, session.starttime; report.timestamp = 0; while (session in progress) { wait interval; report.statistics = update statistics; report.curtimestamp += interval; if encryption required report_data = encrypt(report, encrypt parameters); else report_data = report; raqmon_pdu = header, report_data; send raqmon-pdu; } } RRC: listen on raqmon port when ( raqmon_pdu received ) { decrypt raqmon_pdu.data if needed if report.identifier in database if report.current_time_stamp > last update update session statistics from report.statistics else discard report } Siddiqui, et al. Standards Track [Page 46]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Authors' Addresses Anwar Siddiqui Avaya 307 Middletown Lincroft Road Lincroft, NJ 80302 USA Phone: +1 732 852-3200 EMail: anwars@avaya.com Dan Romascanu Avaya Atidim Technology Park, Bldg #3 Tel Aviv, 61131 Israel Phone: +972-3-645-8414 EMail: dromasca@avaya.com Eugene Golovinsky Alert Logic Phone: +1 713 918-1816 EMail: gene@alertlogic.net Mahfuzur Rahman Samsung Information Systems America 75 West Plumeria Drive San Jose, CA 95134 USA Phone: +1 408 544-5559 Yongbum Yong Kim Broadcom 3151 Zanker Road San Jose, CA 95134 USA Phone: +1 408 501-7800 EMail: ybkim@broadcom.com Siddiqui, et al. Standards Track [Page 47]
RFC 4712 Transport Mappings for RAQMON PDU October 2006 Full Copyright Statement Copyright (C) The Internet Society (2006). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgement Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Siddiqui, et al. Standards Track [Page 48]
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