Internet Draft Anwar Siddiqui Avaya Inc. Dan Romascanu Avaya Inc. Eugene Golovinsky BMC Software 15 Jan 2003 Real-time Application Quality of Service Monitoring (RAQMON) Framework Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as "work in progress." To view the list Internet-Draft Shadow Directories, see http://www.ietf.org/shadow.html. Copyright Notice Copyright (C) The Internet Society (2002). All Rights Reserved. Abstract There is a need to extend the RMON framework [RFC2819] to monitor end devices such as IP Phones, Pagers, Instant Message Clients, Mobile Phones, and various other Hand held computing devices. This memo proposes an extension of RMON Framework to allow Real-time QoS Monitoring of various Applications that runs on these types of end devices and allows such information be integrated with RMON Framework via SNMP. Distribution of this memo is unlimited. Table of Contents RMON WG Expires July 2003 [Page 1] INTERNET DRAFT RAQMON Framework Jan 2003 Status of this Memo 1 Abstract 1 1 Introduction 2 2 RAQMON Functional Architecture 3 3 A Simple list of Metrics pre-defined in BASIC PDU 9 4 Overview of RAQMON Framework 18 5 Normative References 22 6 Informative References 22 7 Intellectual Property 24 8 Security Considerations 24 9 IANA Considerations 25 10 Authors' Addresses 26 A Full Copyright Statement 26 1. Introduction There is a need to extend the RMON framework [RFC2819] to monitor end devices such as IP Phones, Pagers, Instant Message Clients, Mobile Phones, and various other Hand held computing devices. This memo proposes an extension of RMON Framework to allow Real-time QoS Monitoring of various Applications that runs on these types of end devices and allows such information be integrated with RMON Framework via SNMP. An end-to-end user experience of the quality of service (QoS) of such applications is a combination of types of applications level transactions, network resources and host performance. And at any given point, it's the applications at these devices that can correlate such data and report actual statistics to reflect end-to- end view. Real-Time Application QOS Monitoring (RAQMON) Framework provides an option to theses applications and end devices to report specific parameters, appropriate for an application context. An application running on a specific end device reports a selected set of metrics derived from the monitoring of network packets, local host performance and application level transactions. In particular, Real-time Application QoS Monitoring (RAQMON) Framework allows: a. A set of Protocol Data Unit (PDU) with selectable QOS performance metrics to be sent by the "applications" running on the end devices. The metrics are defined through reference to existing IETF, ITU and other standards organizations' documents. These PDUs are transmitted over Real Time Control Protocol (RTCP) or Simple Network Management Control Protocol (SNMP) to ensure reuse of existing internet standards. RMON WG Expires July 2003 [Page 2] INTERNET DRAFT RAQMON Framework Jan 2003 b. A capability to accommodate new parameters not included in the initial list, as Type Length Value(TLV) to be defined by the Application Developers within RAQMON Framework. c. A portion of the Management Information Base (MIB) as an extension of RMON MIB Modules for use with network management protocols in the Internet community. This memo provides definition of RAQMON entities, a functional architecture and behavior of various components. Further details around RAQMON specification is published in RAQMON QOS PDU [darft- ietf-rmonmib-raqmon-pdu-xx.txt] and RAQMON MIB [darft-ietf-rmonmib- raqmon-mib-xx.txt] drafts. RAQMON QOS PDU [darft-ietf-rmonmib-raqmon-pdu-xx.txt] draft describes how various protocol PDUs can be transported over existing Application level transport protocol like the Real Time Communication protocol (RTCP) and Simple Network Management Protocol (SNMP) to transport various Protocol Data Units. RAQMON MIB [darft-ietf-rmonmib-raqmon-mib-xx.txt] draft defined the Management Information Base (MIB) for use with network management protocols in the Internet community. The document proposes an extension to the Remote Monitoring MIB [RFC2819] to accommodate RAQMON solution. 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. RAQMON Functional Architecture This document continues the architecture created in the RMON MIB [RFC2819] by providing analysis of application performance as experienced by end-users on a specific end point and correlating such performance to its underlying transport network characteristics, applications level transactions and host performance. RAQMON framework is based on three functional components named below. - RAQMON Data Source (RDS) - RAQMON Report Collector (RRC) - RAQMON MIB Structure A RAQMON Data Source (RDS) is a functional component that acts as a source of data for monitoring purposes. End devices like IP Phones, cell Phones, pagers etc. and application clients like Instant Message RMON WG Expires July 2003 [Page 3] INTERNET DRAFT RAQMON Framework Jan 2003 Clients, Soft phones in PC is envisioned to act as an RDS within RAQMON Framework. A RAQMON Report Collector (RRC) receives statistics from multiple RDSs, analyzes it, and stores such information appropriately. A RAQMON Report Collector (RRC) is envisioned to be a network server serving an administrative domain defined by the network administrator. RAQMON Management Information Base (RAQMON MIB) extends Remote Monitoring MIB [RFC2819] to accommodate RAQMON Framework. +----------------------+ +---------------------------+ | IP End Device | | IP End Device >----+ | |+--------------------+| |+--------------------+ | | || APPLICATION || || APPLICATION | | | || -Voice over IP <----(1)----> -Voice over IP >- + | | || -Instant Messaging|| || -Instant Messaging| | 3 | || -Email || || -Email | 2 | | |+--------------------+| |+--------------------+ | | | | | | | | | | | | +------------------+ | | | +----------------------+ | |RAQMON Data Source|<-+ | | | | (RDS) |<---+ | | +------------------+ | +-----------|---------------+ | (4) RAQMON PDU transported over RTCP APP Packet or SNMP INFORM | +----------------------------+ | | |/ |/ +------------------+ +------------------+ +-------------+ |RAQMON Report | .. |RAQMON Report | |Network Alarm| |Collector (RRC) #n| |Collector (RRC) #1|<--5-->| Manager | +------------------+ +------------------+ +-------------+ Figure 1 - RAQMON Framework. (1) Communication Session between applications (2) Context-Sensitive Metrics (3) Device State Specific Metrics RMON WG Expires July 2003 [Page 4] INTERNET DRAFT RAQMON Framework Jan 2003 (4) RAQMON metrics transmitted over specified interface (Specific Protocol Interface, IP Address, port) (5) RAQMON MIB sent within SNMP notifications. 2.1 RAQMON Data Source (RDS) RAQMON Data Source is a source of data for monitoring purposes. A RDS is primarily responsible for abstracting IP end-devices and applications for the purpose of monitoring with RAQMON Architecture. It gathers the parameters defined in table 1 for a particular communication session, and forwards them to the RRC. Since it is envisioned that the RDS functionality will be realized by writing firmware/software running on potentially small, low powered end device, the design of RDS specification and the protocol data units sent from RDS is optimized towards that. 2.1.1 Configuring RAQMON Data Source In order to report statistics to RAQMON report collector, RDSs will need to be configured with some of the following parameters: 1. The time interval between RAQMON PDUs 2. The RRC IP address and port (i.e. Ports are IANA Registered and could different based on protocol chosen to transport PDU) 3. The encryption/authentication scheme required and its parameters (if used). A RDS can use one or more of the following mechanisms to gain access to configuration parameters: - RDS acts as a tftp client and download text scripts to read the parameters - RDS acts as a DHCP Client and get RRC address information via DHCP options - RDS acts as a DNS client and get DNS records - RDS acts as a LDAP Client and use directory look-ups - RDS manually configured using command line interface (CLI), Telephone User Interface (TUI) Compliance to RAQMON specification does not require usage of any specific mechanisms mentioned above. Administration and provisioning RDSs is beyond the scope of this memo and left upon the implementers to choose appropriate provisioning mechanisms for a system. 2.2 RAQMON Report Collector (RRC) A RAQMON Report Collector (RRC) receives RAQMON statistics from RMON WG Expires July 2003 [Page 5] INTERNET DRAFT RAQMON Framework Jan 2003 multiple RDSs, analyzes it, and stores it in RAQMON MIB. The RRC is envisioned to be computationally resourceful, providing a storage and aggregation point for a set of RDSs. RAQMON Framework allows multiple RDSs engaged in a communication session with each other to report statistics to multiple different RRCs as the RDSs may belong to different administrative domain. To accommodate such scenarios, its beyond the scope of RRC functional specification to establish relationship between multiple communicating RDSs and a management application can be written to correlate information residing in multiple administrative domain. 2.3 RAQMON Protocol Data Unit (PDU) RAQMON Protocol Data Unit (PDU) provides a generic structure exchanged between the RDS and RRC to report application and device level statistics. RAQMON Framework uses a PUSH mechanism from RDSs to RRC to gather application and device level statistics. There are 2 types of PDUs within the RAQMON Framework: BASIC PDU: A BASIC PDU provides mechanisms to report some frequently used parameters from a pre listed parameter suit defined in table 1. Application developers have the flexibility to make an RDS report a sub-set of these pre-set parameters to RRC appropriate for an application context. For example, An IP Phone developer might want to use RAQMON BASIC PDU to report End-to-End Delay, Jitter, packet loss etc while the Instant Message client can use the same BASIC PDU to report only Packet Loss and End-to-End Delay. APP PDU: Since is difficult to design a BASIC PDU that meets the needs of all applications, RAQMON provides APP PDUs for further extension required to convey application, vendor, device etc. specific parameters for future usage. Additional parameters can be defined within payload of the APP PDU as Type length Value (TLV) pairs and defined by the application developers or vendors. RAQMON PDUs, provides RDSs the flexibility to decide the parameters, an end device/application is willing to report. RAQMON PDUs also provide the RRCs the flexibility to store the parameters an administrative domain feel important for a domain. The memo [darft-ietf-rmonmib-raqmon-pdu-xx.txt] contains detailed RAQMON PDU specifications. 2.4 RDS/RRC Network Transport Protocol interface In order to re-use existing internet protocol, RAQMON PDUs will RMON WG Expires July 2003 [Page 6] INTERNET DRAFT RAQMON Framework Jan 2003 either use RTCP or SNMP to transport the RAQMON PDUs. Transport protocol used to carry RAQMON PDUs would have affects on the reliability of PDUs. This section describes requirements to carrying RAQMON PDUs within a particular network an associated choice of protocol. RAQMON PDUs relies on the underlying protocol(s) to provide a length indication. The maximum length of the RAQMON data packet is limited only by the underlying protocols. The memo [darft-ietf-rmonmib-raqmon-pdu-xx.txt] defines the RAQMON QOS PDU and describes how PDUs are transported over existing Application level transport protocol like Real Time Communication protocol (RTCP) and Simple Network Management Protocol (SNMP). Carrying RAQMON PDUs over RTCP and SNMP being as underlying transport protocols has following advantages: 1. Lightweight - RDSs will be implemented on low powered embedded devices with limited device resources such as IP Phones, Hand held computing devices, cellular phones, pagers etc. 2. Scalable - Since RRCs need to interact with very large number of RDSs, it is a requirement that the protocol be scalable. 3. Security - Since RAQMON statistics may contain sensitive system information it is imperative that the protocol provides a strong security solution and re-using RTCP and SNMP achieves that. 4. It is recommended that no more than 10% network bandwidth in a system be used for RDS/RRC reporting. More frequent reports from an RDS to RRC would imply requirements for higher network bandwidth usage. 5. NAT Friendly - Comply with [RFC3235], so that an RDS could communicate with an RRC through a Firewall/Network Address Translation device. 6. RAQMON PDUs may be lossy, as RAQMON deals with getting statistics rather than billing type critical functionalities. However RAQMON PDUs with appropriate network transport protocol like TCP would guarantee reliability of the RAQMON PDU transport. In Future, if RAQMON PDUs are to be carried in an underlying protocol that provides the abstraction of a continuous octet stream rather than messages (packets), an encapsulation of the RAQAMON packets must be defined to provide a framing mechanism. Framing is also needed if the underlying protocol may contain padding so that the extent of the RMON WG Expires July 2003 [Page 7] INTERNET DRAFT RAQMON Framework Jan 2003 RAQMON payload cannot be determined. The framing mechanism is not defined in this document. Carrying several RAQMON packets in one network or transport packet reduces header overhead. 2.5 Mapping RAQMON PDUs in existing Transport Protocol Though, RAQMON PDUs can be transported over RTCP as well as SNMP, it is not mandatory for either RDS or RRC to implement both transport protocols interfaces. However since RRCs are computationally resourceful, it is recommended that RRCs support both RTCP and SNMP interface to accommodate RDSs with one protocol interface. Usage of RTCP (Section 2.5.1) and SNMP Inform (Section 2.5.2) to carry RAQMON PDUs is described in the following sub-sections. 2.5.1 Usage of RTCP to carry RAQMON PDUs RAQMON Framework is comprised of unidirectional exchange of PDUs between RDSs and an RRC. The protocol data units are mapped to a connectionless datagram service (UDP). To accommodate RTCP as the RAQMON PDU Transport, RRC-RTCP interface need to recognize 2 simple types of RAQMPON PDUs(i.e. like RTCP APP reports) namely BASIC PDU and APP PDU as described above. + During a monitored communication session, the RDSs will send a RAQMON PDU to a target RRC with the QOS metrics appropriate for a specific application context. RDS embeds RAQMON PDUs as a payload to RTCP APP Packet [RFC 1889]. + Since the PDUs carry "complete" set of information, the reporting session between RDS and RRC is stateless. RAQMON PDU transport over RTCP is a simple one-way send protocol. The RDSs will not be capable of inferring successful delivery PDUs over a lossy network RRCs could use specific fields of each RAQMON PDUs along with unique parameters like 6 Octet MAC address, IP Address, Application name, address to correlate a received RAQMON PDU to an ongoing session. 2.5.2 SNMP INFORM PDUs as RDS/RRC Network Transport Protocol SNMP INFORM PDU are re-used to transport RAQMON PDUs with following + RDSs embeds RAQMON PDU in SNMP INFORM to report RAQMON statistics. RMON WG Expires July 2003 [Page 8] INTERNET DRAFT RAQMON Framework Jan 2003 + To keep the RDS realization simple and keep the protocol lightweight, the RDSs will not be REQUIRED to respond to SNMP requests like get, set, etc., as an SNMP compliant responder would. + If the RRC chooses to implement an SNMP manager, an SNMP INFORM Response could be sent for each associated SNMP INFORM originated by the RDS. + The RDS may ignore the SNMP INFORM Responses, or, if better reliability is required, will wait for the Inform response, retransmitting the original Inform PDU every M seconds until it has been sent N times. + The SNMP INFORM transport for RAQMON PDUs can use one of the two UDP ports assignments: - Standard UDP port 162 used for SNMP Notifications, if full SNMP entities implementations are present in the RRC and RDS - IANA assigned UDP port 5YYYY for RAQMON PDUs carried over SNMP, for the cases when at least one of the RRC and RDS does not support a full implementation of the SNMP entities. The benefits of using SNMP Informs are: - Using a well-known protocol. - Privacy and authentication are covered by SNMPv3 - Limited or no need for specific RAQMON-protocol code in the RRC, as it can use an SNMP manager implementation to process Informs. The drawback of this approach is the overhead SNMP puts on low- powered RDSs, for instance - BER encoding. 3. A Simple list of Metrics pre-defined in BASIC PDU RAQMON BASIC PDUs provide a set of pre-defined list of parameters frequently used by the application developers. It is an extremely challenging task to define "appropriate metrics" to be presented in a BASIC PDU as metrics are context-sensitive. However one can also notice enough commonalities between the various QOS parameters associated to various applications such that the task of defining a "simple metrics" is feasible. This memo defines a simple metric to be contained in BASIC PDU that in essence captures the performance and associated quality-of-service parameters of a communication session. Within RAQMON Framework one could use APP PDUs to add parameters not covered in the BASIC PDU for extensions to this list. RAQMON framework also provides a mechanism to add and drop various RMON WG Expires July 2003 [Page 9] INTERNET DRAFT RAQMON Framework Jan 2003 parameters to this metrics as defined in Table 1 below to accommodate application context sensitivity: 1. Data Source Name (DN) 2. Receiver Name (RN) 3. Data Source Address (DA) 4. Receiver Address (RA) 5. Data Source Device Port used 6. Receiver Device Port used 7. Session Setup Date/Time 8. Session Setup delay 9. Session duration 10. Session Setup Status 11. End-to-End Delay 12. Inter Arrival Jitter 13. Total number of Packets Received 14. Total number of Packets Sent 15. Total number of Octets Received 16. Total number of Octets Sent 17. Cumulative Packet Loss 18. Packet Loss in Fraction 19. Source Payload Type 20. Receiver Payload Type 21. Source Layer 2 Priority 22. Destination Layer 2 Priority 23. Source Layer 3 Priority RMON WG Expires July 2003 [Page 10] INTERNET DRAFT RAQMON Framework Jan 2003 24. Destination Layer 3 Priority 25. CPU utilization in Fraction 26. Memory utilization in Fraction 27. Application Name/version 28. RAQMON Optional Flags (ROF) Table 1: RAQMON Metrics Definition Various parameters listed in table 1 are defined below. The definition presented here is meant to provide guidance to implementers. No claim is made that the definitions presented here are appropriate for a particular application need. Data Source Name (DN): The DN item could be of various formats as needed by the application. Few instances of DN could be but not restricting to * "user@host", or "host" if a user name is not available as on single-user systems. For both formats, "host" is either the fully qualified domain name of the host from which the payload originates, formatted according to the rules specified in [RFC1034], [RFC1035] and Section 2.1 of [RFC1123]; The DN value is expected to remain constant for the duration of a session. Examples are "big-guy@ip- phone.bigcompany.com" or "big-guy@135.8.45.178" for a multi-user system. On a system with no user name, examples would be "ip- phone4630.bigcompany.com". It is recommended that the standard host's numeric address not be reported via DN parameter as Data Source Address (DA) parameter is used for that purpose. * Another instance of a DN could a valid E.164 phone number, a SIP URI or any other form of telephone or pager numbers. It is recommended that the phone number should be formatted with the plus sign replacing the international access code. For example, "+88 02 123 45678" for a number in Bangladesh. It is expected that a Data Source Name (DN) will remain constant within a communication session. Receiver Name (RN): Same as Data Source Name (DN). Data Source Address (DA): Data Source Address (DA) parameter should be represented as the standard ASCII representation of the host's numeric address. This could be an IPv4 Address, IPv6 Address, network RMON WG Expires July 2003 [Page 11] INTERNET DRAFT RAQMON Framework Jan 2003 address assignments such as the Net-10 assignment proposed in [RFC1597] or any other form of numeric address represented in ASCII. It is expected that a Data Source Name (DN) would remain constant within a communication session. DN and DA are intended to give the application writers an opportunity to uniquely identify a record associated to a session. However application writers should be aware that private network address assignments such as the Net-10 assignment may create network addresses that are not globally unique. To handle this case, the burden is on the application either by converting private addresses to public addresses if necessary to keep private addresses from being exposed or by creating an application specific extension. Receiver Address (RA): Same as Data Source Address Data Source Device Ports used: This parameter is used to indicate the port used for a particular session or sub-session used for communication. Example of port includes TCP Port, UDP Port, RTP Port etc. It is not expected that a Data Source Device Ports would remain constant within a communication session. Receiver Device Ports used: Same as Data Source Device Ports used. Session Setup Date/Time Indicates the wallclock time when the RAQMON packet was sent so that it may be used by the RRC to store Date/Time. Wallclock time (absolute time) is represented using the timestamp format of the Network Time Protocol (NTP), which is in seconds relative to 0h UTC on 1 January 1900 [RFC1305]. Session Setup delay: Session setup delay indicates the duration of time required by a network communication controller to set a media path between the communicating entities or the end devices. For example in VoIP systems a session setup time can be measured as the last DTMF button pushed to the first ring back tone that indicates that the far end is ringing. However as these definitions are very specific to the type of system used and implementation details of such system, no claim is made about the definition presented here are appropriate for a particular application need and left upon the implementers to define. Session duration: This parameter describes how long a session or a sub-session lasted. Session Setup Status: This parameter is intended to report status of a session in order to support applications those need to display status in realtime. For example a debugging tool that captures the RMON WG Expires July 2003 [Page 12] INTERNET DRAFT RAQMON Framework Jan 2003 status of a call setup as soon as a call is established or a tool that captures why a session failed or how many RSVP sessions failed etc. End-to-End Delay: End-to-End delay is a key parameter for Application QOS Monitoring. Some applications do not perform well (or at all) if end-to-end delay between hosts is large relative to some threshold value. Erratic variation in delay makes it difficult (or impossible) to support many real-time applications like Voice over IP, Video over IP, Fax over IP etc. RAQMON Framework should allow an application to report either Round Trip Delay or One Way Delay. There are many measurement methodologies available to fill this parameter but this parameter is intended to capture the End-to-End delay as observed by the IP devices at the application layer pertaining to a specific operation environment. While appropriate, it is recommended that specific application layer delays like play out delay, packet sequencing delays, coding, decoding delays be added to transport network delay to report End-to- End delay under RAQMON BASIC PDU. End-to-End delay of underlying transport network can be measured using various methodologies as described in [RFC2681], [RFC2679], [RFC1889] depending on the application needs and left upon the implementers to select appropriate IETF and ITU methodologies to measure End-to-End Delays appropriate for a specific application. Inter-arrival Jitter: Inter-arrival jitter field provides a short- term measure of congestion. The definition of Jitter is context sensitive and measurement specific. Measurement of inter-arrival Jitter is beyond the scope of this document. The jitter measure indicates congestion before it leads to packet loss. Inter-arrival jitter of underlying transport network can be measured using various methodologies and left upon the implementers based on there application need. VoIP Systems can readily acquire Inter-arrival Jitter calculations from RTCP measurements as described in [RFC1889]. Total number of Packets Received: The total number of packets received by the data source since starting transmission up until the time this RAQMON packet was generated. Total number of Packets Sent: Similar to total number of packets received. Total number of Octets Received: The total number of payload octets received in packets by the sender since starting transmission up until the time this RAQMON packet was generated. RMON WG Expires July 2003 [Page 13] INTERNET DRAFT RAQMON Framework Jan 2003 Total number of Octets Sent: Similar to total number of octets received. Cumulative Packet Loss: Packet loss tracks persistent congestion while the jitter measure tracks transient congestion. Since the interarrival jitter field is only a snapshot of the jitter at the time of a report, packet loss indicates the network environment as well as local device losses over time. Packet loss of underlying transport network can be measured using various methodologies e.g. as described in [RFC2680], [RFC1889] and local device level packet losses ought to be captured by the local device specific algorithms. Measurement methodologies are left upon the implementers based on their application need. Packet loss in Fraction: Same as Packets loss but expressed in percentage Source Payload Type: Defines payload formats (e.g. media encodings) as sent by the data source. e.g. ITU G.711-(law, ITU G.729B, H.263, MPEG-2, ASCII etc. This document follows the same payload type constants as defined in [RFC1890]. Destination Payload Type: Similar to Source Payload Type. Source Layer 2 Priority: Many devices use Layer 2 technologies to prioritize certain type of traffic in the Local Area Network environment. For example the 1998 Edition of IEEE 802.1D [IEEE802.1D] "Media Access Control" Bridges contains expedited traffic capabilities to support transmission of time critical information and many devices use the standard to mark Ethernet frames according to IEEE 802.1p standard. Details on these can be found in IEEE 802.1Q "Virtual Bridged LAN" specifications. 802.1p has been Incorporated into ISO/IEC 15802-3 1998 [IEEE802.1Q]. Source Layer 2 RAQMON field indicates Layer 2 values used by the Data Source to prioritize these packets in the Local Area Networks environment. Source Layer 3 Priority: Various Layer 3 technologies are in place to prioritize certain type of traffic in the internet. For example traditional IP Precedence [RFC791], Type Of Service (TOS) [RFC1349],[RFC1812] or more recent technologies like Differentiated Service [RFC2474][RFC2475] is achieved by using the TOS octet in IPv4 and the Traffic class Octet in IPv6 are used to prioritize traffic. Source Layer 3 RAQMON field indicates appropriate Layer 3 values used by the Data Source to prioritize these packets. Destination Layer 2 Priority: Same as Source Layer 2 Priority. Destination Layer 3 Priority: Same as Source Layer 3 Priority. RMON WG Expires July 2003 [Page 14] INTERNET DRAFT RAQMON Framework Jan 2003 CPU utilization in Fraction: This parameter captures the IP Device CPU usage rate to indicate current state of the local IP Device resource which has a very critical implications on QOS implications of an end device. e.g. x % CPU busy averaged over session duration. Memory utilization in Fraction: This parameter captures the IP Device Memory usage rate to indicate current state of the local IP Device resource which has a very critical implications on QOS implications of an end device. e.g. y % memory utilized over session duration. Application Name/version Application Name/version parameter gives the name and possibly version of the application associated to that session or sub-session, e.g., "XYZ VoIP Agent 1.2". This information may be useful for scenarios where end device is running multiple applications with various priorities and could be very handy for debugging purposes. RAQMON Optional Flags (ROF): These flags are open to various vendors to be used for application specific bit level signaling. For example RDS can report various numeric status code to RRCs using these bits. For example, the end devices that support RSVP to setup a communication session would be successful in acquiring RSVP reservation in one direction but not the other. A specific 8-bit failure code can be used to indicate each failure code. One could also use these bits to indicate RAQMON packet sequence number. These 8-bit Optional Flags are interpreted by the application, not by the RRC and usage of these left at the application developer's discretion. 3.1 Measurement Methodology It is not the intent of this document to recommend a methodology to measure any of the QOS parameters defined in table 1. Measurement algorithms are left upon the implementers and equipment vendors to choose. There are many different measurement methodologies available for measuring application performance (e.g., probe-based, client- based, synthetic-transaction, etc.). This specification does not mandate a particular methodology - it is open to any that meet the minimum requirements. Conformance to this specification requires that the collected data match the semantics described herein. 3.2 Report Aggregation and Statistical Data processing The RAQMON MIB is designed to provide minimal aggregations of various RAQMON Parameters defined in table 1. RAQMON MIB is designed to not to provide extensive aggregations like APM MIB [29] or TPM MIB [30] and one should use APM and TPM MIBs to aggregate based on protocols (e.g. Performance of HTTP, RTP) or based on application (e.g. RMON WG Expires July 2003 [Page 15] INTERNET DRAFT RAQMON Framework Jan 2003 Performance of VoIP, Video Applications). In RAQMON Framework, RDSs are not burdened by statistical data processing as RDSs may be co-resident in end-devices and could be resource constrained. Various aggregations are performed by the RRC. Aggregation of RAQMON parameters collected over a period of time is dependent on aggregation algorithms. In the RAQMON MIB, aggregation can be performed only on specific RAQMON metrics parameters specified below: End-to-End Delay Inter Arrival Jitter Cumulative Packet Loss Packet Loss in Fraction CPU utilization in Fraction Memory utilization in Fraction The aggregation always results in the following statistics: Mean End-to-End Delay Min End-to-End Delay Max End-to-End Delay Mean Inter Arrival Jitter Min Inter Arrival Jitter Max Inter Arrival Jitter Mean Cumulative Packet Loss Min Cumulative Packet Loss Max Cumulative Packet Loss Mean Packet Loss in Fraction Min Packet Loss in Fraction Max Packet Loss in Fraction RMON WG Expires July 2003 [Page 16] INTERNET DRAFT RAQMON Framework Jan 2003 Mean CPU utilization in Fraction Min CPU utilization in Fraction Max CPU utilization in Fraction Mean Memory utilization in Fraction Min Memory utilization in Fraction Max Memory utilization in Fraction For this document following aggregation definitions are used: Mean: Mean is defined as the statistical average of a metric over the duration of a communication session. For example if End-to-End delay metric of an end device within a communication session is reported N times by the RDS, then the Mean End-to-End Delay is the average End- to-End Delay metric over N entries. Min: Min is defined as the statistical minimum of a metric over the duration of a communication session. For example if End-to-End delay metric of an end device within a communication session is reported N times by the RDS, then the Min End-to-End Delay is the minimum of all N End-to-End Delay metric entries in the table. Max: Max is defined as the statistical maximum of a metric over the duration of a communication session. For example if End-to-End delay metric of an end device within a communication session is reported N times by the RDS, then the Max End-to-End Delay is the maximum of all N End-to-End Delay metric entries in the table. 3.3 Keeping Historical Data and Storage It is evident from the document that, RAQMON MIB data need to be managed to optimize storage space. Enormous volume of data gathered in a communication session could be optimized for storage space by performing and storing only aggregated RAQMON metrics for history if required. Such storage space optimization can be performed in following ways: RMON WG Expires July 2003 [Page 17] INTERNET DRAFT RAQMON Framework Jan 2003 1. Store data in the MIB only at the end of a communication session (i.e. after receiving an END packet), the aggregated data could be stored in RAQMON MIB as Mean, Max or Min entry and saved for historical purposes. This will minimize storage space requirement, as instead of a column in a table, only few scalars will be used to store a metric. 2. A time based algorithms that aggregate data over a specific period of time within a communication session (i.e. thus requiring less entries) also reduces storage space requirements. For example, if RDS sends data out every 10 seconds and RRC writes to the RAQMON MIB once every minute, for every 6 data points there will be one MIB entry. 3. Clearing up historical data periodically over a calendar time using administration policy can perform further storage space optimization. For example, an administrator could create a policy such that all historical data get cleared up every 60 days. Such policies are interpreted by the application, not by the RRC and usage of these policies left at the application developer's discretion. 4. Overview of RAQMON Framework RAQMON is a framework that extends RMON within which various end devices and applications can be monitored and appropriate management applications could take advantage of such information to perform network management and administrative operations. In summary, RAQMON Framework has following attributes: + The monitoring function is performed in real-time during each communication session. + Any IP end points and applications who are producers or consumers of IP Traffic, could use RAQMON Framework to report QOS statistics. RAQMON QOS statistics can be used by many Real-Time Applications like Voice over IP, Fax over IP, Video over IP, Instant Messaging etc. and non-real time applications like Email, ftp/tftp based downloads, e- business style transactions, web access from handheld devices etc to report QOS statistics within one single framework. + RAQMON Framework is simplex, i.e., it RDSs reports statistics for unidirectional data flows as experienced by the end device or application. + RAQMON specifies a protocol data unit and provides specifications to transport the RAQMON PDU over existing Internet standards like RTCP APP Packet and SNMP INFORM. RMON WG Expires July 2003 [Page 18] INTERNET DRAFT RAQMON Framework Jan 2003 RAQMON provides a framework to report QOS statistics for simplex flows, i.e., it reports statistics only in one direction. Therefore, within RAQMON Framework, a RAQMON PDU is logically viewed QOS parameters as perceived by the reporting end device or applications. RAQMON operates on top of RTCP, SNMP, TCP, UDP, IPv4 or IPv6 occupying the place of a payload specification at the application layer in the protocol stack. However, RAQMON PDUs does not transport application data but is rather uses existing internet protocols like RTCP APP Packet and SNMP INFORM to be transported from a RDS to RRC. Like the implementations of routing and management protocols, an implementation of RAQMON will typically execute in the background, not in the data forwarding path. RAQMON PDUs by itself is not a transport protocol; RAQMON PDUs are designed to operate with current and future internet transport protocols. + RAQMON Framework is agnostic to the underlying measurement methodology used to quantify a QOS parameter. RAQMON PDUs offer an entry (a.k.a. "Name") to be filled in by application specific software which with a specific "value". Since RAQMON PDUs are common data formats commonly understood by RDS and RRC to exchange RAQMON Statistics (i.e. "Name" and "Value" pair), measurement methodologies are out of the scope of RAQMON specification. It is also out of the scope of PDU specification to validate specific measurement methodology used to gather a "value". + RAQMON Framework allows future extensibility by adding fields to RAQMON APP PDUs. New Parameters not covered in the BASIC PDU could be added to RAQMON APP PDU as Type Length Value (TLV) field. This mechanism can also be used to accommodate application and vendor specific extensions not covered in BASIC PDU. + In order to facilitate complete End-to-End view and to portray end user experience, the RAQMON correlate statistics that involves: i. "User, Application, Session" specific parameters - e.g. Instant Message vs. VoIP, session setup time, session duration etc. ii. "IP end device" specific parameters during a session e.g. CPU Usage, memory usage iii. "Transport network" specific parameter during a session (e.g. End-to-End Delay, One Way Delay, Jitter, Packet loss etc. User experience of an application running on a specific IP end point has lot to do with the type of application an user is running, local end device resources available as well as the underlying transport network capabilities. RMON WG Expires July 2003 [Page 19] INTERNET DRAFT RAQMON Framework Jan 2003 + RAQMON parameters in BASIC PDU are selectable by the RDS and Application implementation. End-to-End QOS view is sensitive to application type, device and transport network. Though RAQMON PDUs are capable of carrying various pre-specified parameters but the BASIC PDUs provide options to select a sub-set of those parameters from the metrics definition list, to fit the needs of the application-context. The Application implementer controlling the RDS will be responsible for choosing a set of parameters, as "monitoring context" is application specific. For example an IP Soft Phone application running on a PC probably be willing to report "Jitter" to RRC however an Email Application running on the same host may not use the "Jitter" parameter to report to RRC as Jitter is deemed to be not so critical for E-mail Application. + Monitored statistics is reported by the RAQMON Data Source (RDS) at will. Content of the RAQMON PDUs, Transmission intervals between various RAQMON PDUs etc. is controlled by the RDSs administrative domain policy. Though monitoring is a useful function but there are various operation scenarios where monitoring could be expensive and degrade the QOS of an application. There are also restrictions imposed on end devices based on the administrative domains. For example, an Enterprise IP Phone user is managed by the enterprise Telecom manager, but the Service Level Agreements is monitored by the Enterprise IT Managers. In such an environment, IP Phones may be required to report QOS Problems to various administrative authorities restricted by the administration domain policy. A RDS Driven reporting mechanism allows enough flexibility to accommodate various administrative constraints. + Quality of service parameters of each communication session should be captured and stored "completely". A communication session may consist of one or more combinations of transaction-oriented, throughput-oriented, or streaming-oriented operations. For example, the quality-of-service definition of a Video over IP call using Video Phones involves: - Caller Video Phone signaling for call setup that includes a transaction with a session processing server which locates/connects the callee using a protocols like SIP, H.323 or MGCP. RMON WG Expires July 2003 [Page 20] INTERNET DRAFT RAQMON Framework Jan 2003 - Eventually the video phone source/sinks media streams between two IP end points using RTP as a result of successful session setup transaction In this particular application scenario, the session set up timing is as critical as the end-to-end delay per packet of audio and video media streams. The RAQMON PDUs should provide a capability to capture such session specific data. RAQMON draft would use the following definitions of transactions as defined in the APM MIB [WALDBUSSER]: Transaction-Oriented: These transactions have a fairly constant workload to perform for all transactions. The responsiveness metric for transaction-oriented applications is application response time, the elapsed time between the user's request for service (e.g. pushing the submit button or pressing DTMF in IP Phones) and the completion of the request (e.g. displaying the results or getting a ring back). Throughput-Oriented: These transactions have widely varying workloads based on the amount of data requested. The metric for throughput- oriented applications are expressed in is Kilobits per second (Kbps) or Mega bits per second (Mbps). Streaming-Oriented: These transactions deliver data at a constant metered rate of speed regardless of excess capacity in the networking and computing infrastructure. However, when the infrastructures cannot deliver data at this speed, interruption of service or degradation of service can result. + Within RAQMON Framework, a report on a communication session between users captures the entire session by keeping records of all the sub-sessions performed within that session. A generic communication session between two users can be modeled as multiple sub-sessions within a communication session. For example a video call between two users would capture Quality of Service parameters of a session for Audio, Video and Data separately but within one compound report as it reflects the true nature of the communication session. It is easier for an end device to correlate between these sub-sessions and report the End-to-End QOS parameters of that session in a compound report. + RAQMON Framework design is embedded device friendly. The applications covered under the RAQMON Charter have become such a commodity in our everyday lives that there are lots of simple embedded smart devices being developed by various vendors at an RMON WG Expires July 2003 [Page 21] INTERNET DRAFT RAQMON Framework Jan 2003 enormous rate. Application Service Providers, Network Service Providers, Enterprise operators, IT Managers etc. have an inherent need to gather QOS Reports of these devices and applications to manage there networks and services. It is the objective of this draft to deliver a simple but easy to deploy monitoring solution. + RAQMON MIB is agnostic to the transport protocol used to carry RAQMON PDUs between RDS and RRC. 5. Normative References [RFC2819] Waldbusser, S., "Remote Network Monitoring Management Information Base", STD 59, RFC 2819, May 2000 [RFC1889] Henning Schulzrinne, S. Casner, R. Frederick, and V. Jacobson, "RTP: A Transport Protocol for Real-Time Applications" RFC 1889, January 1996. [RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791, September 1981. 6. Informative References [RFC1890] H. Schulzrinne, "RTP Profile for Audio and Video Conferences with Minimal Control" RFC 1890, January 1996. [RFC1305] Mills, D., "Network Time Protocol Version 3", RFC 1305, March 1992. [RFC1034] Mockapetris, P., "Domain Names - Concepts and Facilities", STD 13, RFC 1034, November 1987. [RFC1035] Mockapetris, P., "Domain Names - Implementation and Specification", STD 13, RFC 1035, November 1987. [RFC1123] Braden, R., "Requirements for Internet Hosts - Application and Support", STD 3, RFC 1123, October 1989. [RFC1597] Rekhter, Y., Moskowitz, R., Karrenberg, D., and G. de Groot, "Address Allocation for Private Internets", RFC 1597, March 1994. [RFC2679] G. Almes, S.kalidindi and M.Zekauskas, "A One-way Delay Metric for IPPM", RFC 2679, September 1999 [RFC2680] G. Almes, S.Kalidindi and M.Zekauskas, "A One-way Packet RMON WG Expires July 2003 [Page 22] INTERNET DRAFT RAQMON Framework Jan 2003 Loss Metric for IPPM", RFC 2680, September 1999 [RFC2681] G. Almes, S.kalidindi and M.Zekauskas, "A Round-Trip Delay Metric for IPPM", RFC 2681, September 1999 [WALDBUSSER] Steven Waldbusser, "Application Performance Measurement MIB", draft-ietf-rmonmib-apm-mib-04.txt, July 2001 [DIETZ] Russel Dietz, Robert Cole, "Transport Performance Metrics MIB", draft-ietf-rmonmib-tpm-mib-03.txt, July 2001 [ISO10646] International Standards Organization, "ISO/IEC DIS 10646-1:1993 information technology -- universal multiple-octet coded character set (UCS) -- part I: Architecture and basic multilingual plane," 1993. [UNICODE] The Unicode Consortium, The Unicode Standard New York, New York:Addison-Wesley, 1991. [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, 1998 Edition] [RFC1349] P. Almquist, "Type of Service in the Internet Protocol Suite", RFC 1349, July 1992 [RFC1812] F. Baker, "Requirements for IP Version 4 Routers" RFC1812, June 1995 [RFC2474] K. Nicholas, S. Blake, F. Baker and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC2474, December 1998 [RFC2475] S. Blake, D. Black, M. Carlson, E.Davies, Z.Wang and W.Weiss, "An Architecture for Differentiated Services" RFC2475, December 1998 [SIDDIQUI1] A. Siddiqui, D.Romascanu, E. Golovinsky, and R. Smith, "Real-time Application Quality of Service Monitoring (RAQMON) MIB", Internet-Draft, draft-siddiqui-rmonmib-raqmon-mib-01.txt, February 2002 [SIDDIQUI2] A. Siddiqui, S. Waldbusser, D.Romascanu, and E. Golovinsky, "Protocol Data Units for Real-time Application Quality of Service Monitoring (RAQMON)", Internet-Draft, draft-ietf-raqmon-pdu- 00.txt, January 2003 RMON WG Expires July 2003 [Page 23] INTERNET DRAFT RAQMON Framework Jan 2003 [SIDDIQUI3] A. Siddiqui, D.Romascanu, E. Golovinsky, and R. Smith, "Real-time Application Quality of Service Monitoring (RAQMON) MIB", Internet-Draft, draft-ietf-rmonmib-raqmon-mib-00.txt, January 2003 7. Intellectual Property The IETF takes no position regarding the validity or scope of any intellectual property 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; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication 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 implementors or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. 8. Security Considerations There are a number of management objects defined in this MIB that have a MAX-ACCESS clause of read-write and/or read-create. Such objects may be considered sensitive or vulnerable in some network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. It is thus important to control even GET access to these objects and possibly to even encrypt the values of these object when sending them over the network via SNMP. Not all versions of SNMP provide features for such a secure environment. SNMPv1 by itself is not a secure environment. 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. It is RECOMMENDED that the implementers consider the security RMON WG Expires July 2003 [Page 24] INTERNET DRAFT RAQMON Framework Jan 2003 features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model [RFC2274] and the View-based Access Control Model [RFC2275] is RECOMMENDED. It is then a customer/user responsibility to ensure that the SNMP entity giving access to an instance of this MIB, 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. It is also imperative that the RAQMON framework be able to provide the following protection mechanisms: 1. Authentication - the RRC should be able to verify that a RAQMON report was originated by whom ever claims to have sent it. 2. Privacy - RAQMON information include identification of the parties participating in a communication session. RAQMON framework should be able to provide protection from eavsdropping, to prevent an un-authorized third party from gathering potentially sensitive information. This can be achieved by using various payload encryption technologies like DES, 3-DES, AES 3. Protection from denial of service attacks directed at the RRC - RDSs send RAQMON reports as a side effect of an external event (for example, a phone call is being received). An attacker can try and overwhelm the RRC (or the network) by initiating a large number of events (i.e., calls) for the purpose of swamping the RRC with too many RAQMON PDUs. To prevent DoS attacks against RRC, the RDS will send the first report for a session only after the session has been in progress for the TBD reporting interval. Sessions shorter than that will not be reported. 4. NAT and Firewall Friendly Design: Presence for IP addresses, TCP/UDP ports information in RAQMON PDUs may be NAT un-friendly. In such a scenario, where NAT Friendliness is a requirement, the RDS may opt to not to provide IP Addresses in RAQMON PDU. Another way to avoid this problem is by using NAT Aware Application Layer Gateways (ALGs) to fill out IP Addresses in RAQMON PDUs. 9. IANA Considerations This memo introduces 2 new ports for IANA registration. This specification registers port 5YYYY as specified in Section 4.5.1 and Port 5XXX as specified in section 4.5.2.2. at http://www.iana.org/numbers.html RMON WG Expires July 2003 [Page 25] INTERNET DRAFT RAQMON Framework Jan 2003 10. Authors' Addresses Anwar A. Siddiqui Avaya Labs 307 Middletown Lincroft Road Lincroft, New Jersey 07738 USA Tel: +1 732 852-3200 Fax: +1 732 817-5922 E-mail: anwars@avaya.com Dan Romascanu Avaya Inc. Atidim Technology Park, Bldg. #3 Tel Aviv, 61131 Israel Tel: +972-3-645-8414 Email: dromasca@avaya.com Eugene Golovinsky BMC Software Inc. 2101 CityWest Blvd. Houston, Texas 77042 USA Tel: +1 713 918-1816 Email: eugene_golovinsky@bmc.com A. 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RMON WG Expires July 2003 [Page 26] INTERNET DRAFT RAQMON Framework Jan 2003 This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS 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. RMON WG Expires July 2003 [Page 27]