Internet Engineering Task Force INTERNET-DRAFT Scott Poretsky Expires in: August 2006 Reef Point Systems Rajiv Papneja Isocore Takumi Kimura NTT SIL Jerry Perser Veriwave February 2006 Benchmarking Terminology for Protection Performance Intellectual Property Rights (IPR) statement: By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Status of this Memo 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Copyright Notice Copyright (C) The Internet Society (2006). Abstract This document provides common terminology and metrics for benchmarking the performance of sub-IP layer protection mechanisms. The performance benchmarks are measured at the IP-Layer, so avoid dependence on specific sub-IP protections mechanisms. The benchmarks and terminology can be applied in methodology documents for different sub-IP layer protection mechanisms such as Automatic Link Protection (APS) for SONET/SDH, Resilient Packet Ring (RPR) for Ethernet, and Fast Reroute for Multi-Protocol Label Switching (MPLS). Poretsky, Papneja, Perser, and Kimura [Page 1] INTERNET-DRAFT Protection Performance Terminology February 2006 Table of Contents 1. Introduction .............................................. 3 2. Existing definitions ...................................... 4 3. Term definitions .......................................... 4 3.1 Paths 3.1.1 Path ............................................... 4 3.1.2 Working Path ....................................... 5 3.1.3 Primary Path ....................................... 5 3.1.4 Protected Primary Path .............................. 6 3.1.5 Backup Path ........................................ 6 3.1.6 Standby Backup Path ................................ 6 3.1.7 Dynamic Backup Path ................................ 7 3.2 Protection 3.2.1 Protection Switching System ......................... 7 3.2.2 Link Protection .................................... 8 3.2.3 Node Protection .................................... 8 3.2.4 Path Protection .................................... 8 3.2.5 Backup Span ........................................ 9 3.3 Failure 3.3.1 Failure Detection .................................. 9 3.3.2 Failover ........................................... 10 3.3.3 Failover Event ...................................... 10 3.3.4 Failure Recovery ................................... 10 3.3.5 Reversion .......................................... 11 3.4 Nodes 3.4.1 Protection-Switching Node .......................... 11 3.4.2 Non-Protection-Switching Node ...................... 12 3.4.3 Failover Node ...................................... 12 3.4.4 Merge Node ......................................... 12 3.5 Metrics 3.5.1 Failover Packet Loss ............................... 13 3.5.2 Reversion Packet Loss ...............................13 3.5.3 Primary Path Latency ............................... 14 3.5.4 Backup Path Latency ................................ 14 3.6 Benchmarks 3.6.1 Failover Time ...................................... 14 3.6.2 Additive Backup Latency ............................. 15 3.6.3 Reversion Time ...................................... 15 4. IANA Considerations ........................................ 16 5. Security Considerations ................................... 16 6. References ................................................ 16 7. Authors' Addresses ........................................ 17 Poretsky, Papneja, Perser, and Kimura [Page 2] INTERNET-DRAFT Protection Performance Terminology February 2006 1. Introduction The IP network layer provides route convergence to protect data traffic against planned and unplanned failures in the internet. Fast convergence times are critical to maintain reliable network connectivity and performance. Technologies that function at sub-IP layers can be enabled to provide further protection of IP traffic by providing the failure recovery at the sub-IP layers so that the outage is not observed at the IP-layer. Such technologies include High Availability (HA) stateful failover. Virtual Router Redundancy Protocol (VRRP), Automatic Link Protection (APS) for SONET/SDH, Resilient Packet Ring (RPR) for Ethernet, and Fast Reroute for Multi-Protocol Label Switching (MPLS). Benchmarking terminology and methodology have been defined for IP-layer route convergence [7,8,9]. New terminology and methodologies specific to benchmarking sub-IP layer protection mechanisms are required. This will enable different implementations of the same protection mechanisms to be benchmarked and evaluated. In addition, different protection mechanisms can be benchmarked and evaluated. The metrics for benchmarking the performance of sub-IP protection mechanisms are measured at the IP layer, so that the results are always measured in reference to IP and independent of the specific protection mechanism being used. The purpose of this document is to provide a single terminology for benchmarking sub-IP protection mechanisms. It is intended that there can exist unique methodology documents for each sub-IP protection mechanism. Figure 1 shows the fundamental model that is to be used in benchmarking sub-IP protection mechanisms. Protection Switching consists of a minimum of two Protection-Switching Nodes with a Primary Path and a Backup Path. A Failover Event occurs along the Primary Path. A tester is set outside the two nodes as it sends and receives IP traffic along the Working Path. The Working Path is the Primary Path prior to the Failover Event and the Backup Path following the Failover Event. If Reversion is supported then the +-----------+ +--------------------| Tester |<-------------------+ | +-----------+ | | IP Traffic | Failover IP Traffic | | | Event | | Primary | | | +--------+ Path v +--------+ | | | |------------------------>| | | +--->| Node 1 | | Node 2 |----+ | |- - - - - - - - - - - - >| | +--------+ Backup Path +--------+ | IP-Layer Forwarding | +-------------------------------------------+ Figure 1. System Under Test (SUT) for Sub-IP Protection Mechanisms Poretsky, Papneja, Perser, and Kimura [Page 3] INTERNET-DRAFT Protection Performance Terminology February 2006 Working Path is the Primary Path after Failure Recovery. The tester MUST record the IP packet sequence numbers, departure time, and arrival time so that the metrics of Failover Time, Additive Latency, and Reversion Time can be measured. The Tester may be a single device or a test system. 2. Existing definitions This document draws on existing terminology defined in other BMWG work. Examples include, but are not limited to: Latency [RFC 1242, section 3.8] Frame Loss Rate [RFC 1242, section 3.6] Throughput [RFC 1242, section 3.17] Device Under Test (DUT) [RFC 2285, section 3.1.1] System Under Test (SUT) [RFC 2285, section 3.1.2] Out-of-order Packet [Ref.[4], section 3.3.2] Duplicate Packet [Ref.[4], section 3.3.3] This document adopts the definition format in Section 2 of RFC 1242. 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 RFC 2119. 3. Term definitions 3.1 Path 3.1.1 Path Definition: A sequence of nodes, , with the following properties: - R1 is the ingress node and forwards IP packets, which input into DUT/SUT, to R2 as sub-IP frames. - Ri is a node which forwards data frames to R[i+1] for all i, 1