INTERNET DRAFT Jae-Hoon Jeong Expires: July 2002 Jung-Soo Park Seung-Yun Lee Yong-Jin Kim ETRI February 2002 One-way Delay Measurement using IPv6 Source Routing 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." 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 Abstract This document specifies a methodology for measurement of the IETF IPPM WG's one-way IP performance metrics such as one-way delay and jitter of subpaths consisting of a specific end-to-end path in IPv6 network as well as end-to-end one-way IP performance metrics. The methodology measures one-way IP performance metrics in use of IPv6 source routing through IPv6 extension headers. Because the methodology can contribute to the finding of congested link or underutilized link, it can provide important information to configure and manage IPv6 network. Jeong, Park, Lee, Kim Expires July 2002 [Page 1] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 Table of Contents Status of this Memo Abstract 1. Introduction 2. Terminology 3. Subpath One-way Delay Measurement 3.1 Overview 3.2 Layout of Measurement Packet 3.3 Example 4. Considerations related to OWDP 5. IPv6 WG Considerations 6. Security Considerations 7. References Authors' Addresses 1. Introduction We need to measure network performance such as delay, loss and jitter in order to manage and configure network. Some tools such as Surveyor and RIPE have been made and being used for end-to-end one-way IP performance measurement [SURVEYOR][RIPE]. Because these can only measure end-to-end IP performance metrics, we can only know the occurrence of congestion in a specific end-to-end path of measured network [RFC2330][RFC2679][RFC2680][DELAY-VARIATION]. Therefore, we have a difficulty in finding exactly the congested or underutilized position of the measured network with these end-to- end measurement tools. In the result, we need to measure one-way delay of subpaths consisting of the problematic end-to-end path. If we try to measure subpath one-way delay between two separate nodes on an end-to-end path of two measurement systems with these tools, intermediate routers should participate in measurement in use of a new protocol for measurement [IPMP]. Namely, the routers should record timestamp in the passing measurement packet and forward the packet to next router or destination. This document describes a methodology that can measure one-way delay and jitter of subpaths consisting of a specific end-to-end path in IPv6 network as well as end-to-end one-way IP performance metrics such as one-way delay, one-way loss and jitter. The methodology doesn't need a new measurement protocol and can measure subpath one-way delay using IPv6 source routing through IPv6 extension headers. 2. Terminology 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 [RFC2119]. New terms are defined below: Jeong, Park, Lee, Kim Expires July 2002 [Page 2] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 Measurement System A host that runs One-way Delay Measurement Protocol [OWDP]. Subpath One-way The one-way delay on a subpath that composes Delay (SOD) an end-to-end path of two measurement systems. Subpath One-way The measurement of SOD. Delay Measurement (SODM) 3. Subpath One-way Delay Measurement 3.1 Overview SODM uses Destination Options header and Routing header to measure subpath one-way metrics between two separate nodes on an end-to-end path of two measurement systems like Figure 1. When a measurement packet transits along an end-to-end path between two measurement systems, all the routers specified in Routing header of a measurement packet timestamp in Destination Options header of the packet. With the timestamps, SOD can be calculated as follows: delay, delay, delay, delay where delay means SOD from node i to node j and node i can be separated from node j by one or more networks. R means intermediate router. [Sender] [R1] [R2] [R3] [Receiver] | || || || | |___[Net1]___||___[Net2]___||___[Net3]___||___[Net4]___| ---------> measurement packet Figure 1. Subpath One-way Delay Measurement (SODM) 3.2 Layout of Measurement Packet A measurement packet consists of IPv6 header, Destination Options header, Routing header, and OWDP-Test Packet as follows [IPv6] [OWDP]: +-------------+------------------+--------------+----------------+ |IPv6 header |Destination header|Routing header|OWDP-Test Packet| | | | | | |Next Header =|Next Header = |Next Header = | | | Destination | Routing | UDP | | +-------------+------------------+--------------+----------------+ Jeong, Park, Lee, Kim Expires July 2002 [Page 3] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 Figure 2. Layout of Measurement Packet for SODM The format of Destination Options header is like Figure 3 [IPv6]: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Next Header | Hdr Ext Len | Option Type | Opt Data Len | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + ~ Option Data ~ + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 3. Format of Destination Options header Next Header (NH) 8-bit selector. Identifies the type of header immediately following the Destination Options header. Uses the same values as the IPv4 Protocol field. Hdr Ext Len (HEL) 8-bit unsigned integer. Length of the Destination Options header in 8-octet units, not including the first 8 octets. Option Type (OT) 8-bit identifier of the type of option. This field has the value of X that indicates SODM. Opt Data Len (ODL) 8-bit unsigned integer. Length of the Option Data field of this option, in octets. Reserved Because the minimum size of extension header is 8 bytes, the remaining 4 bytes must be intialized to zero; ignored on reception. Option Data Variable-length field. Option-Type-specific data. This field contains timestamps. The format of Option Data of Destination Options header is like Figure 4 [OWDP]: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Timestamp[1] + | | Jeong, Park, Lee, Kim Expires July 2002 [Page 4] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + + ~ ~ ~ + + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | + Timestamp[n] + | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4. Format of Option Data of Destination Options header Timestamp[1..n] 64-bit timestamps written by intermediate routers, numbered 1 to n. Routing header is Type 0 and Address[1..n] of intermediate routers are written in Routing header [IPv6]. The format of UDP OWDP-Test Packet is that of UDP packet at OWDP-Test [OWDP]. 3.3 Example A new option type, X which indicates SODM is defined. SODM in Figure 1 is performed as follows: Step 1. Before a measurement packet leaves Sender. Sender timestamps in the payload of measurement packet in Ethernet frame level. Step 2. After a measurement packet leaves Sender and before the packet arrives at router R1. The values of fields of IPv6 header and extension headers are set as follows: IPv6 header: NH = 60 (Destination Options header) Source Address = Sender, Destination Address = R1 Destination Options header: NH = 43 (Routing header), HEL = 0, OT = X, ODL = 4 Routing header: NH = 17 (UDP Packet), HEL = 6, Routing Type = 0, Segments Left = 3 Address[1] = R2 Address[2] = R3 Address[3] = Receiver Step 3. After a measurement packet leaves router R1 and before the packet arrives at router R2. Jeong, Park, Lee, Kim Expires July 2002 [Page 5] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 IPv6 header: NH = 60 Source Address = Sender, Destination Address = R2 Destination Options header: NH = 43, HEL = 1, OT = X, ODL = 12 Timestamp[1] = T1 Routing header: NH = 17, HEL = 6, Routing Type = 0, Segments Left = 2 Address[1] = R1 Address[2] = R3 Address[3] = Receiver Step 4. After a measurement packet leaves router R2 and before the packet arrives at router R3. IPv6 header: NH = 60 Source Address = Sender, Destination Address = R3 Destination Options header: NH = 43, HEL = 2, OT = X, ODL = 20 Timestamp[1] = T1 Timestamp[2] = T2 Routing header: NH = 17, HEL = 6, Routing Type = 0, Segments Left = 1 Address[1] = R1 Address[2] = R2 Address[3] = Receiver Step 5. After a measurement packet leaves router R3 and before the packet arrives at Receiver. IPv6 header: NH = 60 Source Address = Sender, Destination Address = Receiver Destination Options header: NH = 43, HEL = 3, OT = X, ODL = 28 Timestamp[1] = T1 Timestamp[2] = T2 Timestamp[3] = T3 Routing header: NH = 17, HEL = 6, Routing Type = 0, Segments Left = 0 Address[1] = R1 Address[2] = R2 Address[3] = R3 Step 6. When Receiver receives the measurement packet. Jeong, Park, Lee, Kim Expires July 2002 [Page 6] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 Receiver timestamps in the payload of measurement packet in Ethernet Frame Level and copies the pairs of address and timestamp value from extension headers into the payload of the packet before delivering the packet to the upper layer, IPv6 layer. In the result, subpath one-way delay metrics such as one-way delay and jitter as well as end-to-end one-way delay metrics between two measurement systems can be calculated. 4. Considerations related to OWDP SODM of this document can be used nearly without modifying OWDP. The new OWDP Type-P for SODM must be defined. Type-P for SODM is defined as Type-P-One-way-Delay-Subpath-IPv6. 5. IPv6 WG Considerations IPv6 working group must define a new option type which indicates SODM. The option type must be encoded so that router that doesn't support the mechanism of this document relay measurement packet to next router or destination without discarding it. 6. Security Considerations The mechanism of this document follows the security considerations of One-way Delay Measurement Protocol [OWDP]. Measurement systems and routers that participate in measurement need security service. 7. References [RFC2119] S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997. [RFC2330] V. Paxon, G. Almes, J. Mahdavi, M. Mathis, "Framework for IP Performance Metrics" RFC 2330, May 1998. [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 Loss Metric for IPPM", RFC 2680, September 1999. [IPv6] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", RFC 2460, December 1998. [RIPE] RIPE NCC Test-Traffic Measurements home, http://www.ripe.net/test-traffic/ [SURVEYOR] Surveyor Home Page, http://www.advanced.org/surveyor/ Jeong, Park, Lee, Kim Expires July 2002 [Page 7] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 [DELAY-VARIATION] C. Demichelis and P. Chimento, "IP Packet Delay Variation Metric for IPPM", I-D draft-ietf-ippm-ipdv-07, Feb. 2001. http://www.ietf.org/internet-drafts/draft-ietf-ippm-ipdv-08.txt [IPMP] IP Measurement Protocol (IPMP), http://watt.nlanr.net/AMP//IPMP/ipmp-0.3.html [OWDP] S. Shalunov, B. Teitelbaum and M. Zekauskas, "A One-way Delay Measurement Protocol", I-D draft-ietf-ippm-owdp-03, Feb. 2001. http://www.ietf.org/internet-drafts/draft-ietf-ippm-owdp-03.txt Authors' Addresses Jae-Hoon Jeong ETRI / PEC 161 Gajong-Dong, Yusong-Gu Daejon 305-350 Korea Phone: +82 42 860 1664 EMail: paul@etri.re.kr Jung-Soo Park ETRI / PEC 161 Gajong-Dong, Yusong-Gu Daejon 305-350 Korea Phone: +82 42 860 6514 EMail: pjs@etri.re.kr Seung-Yun Lee ETRI / PEC 161 Gajong-Dong, Yusong-Gu Daejon 305-350 Korea Phone: +82 42 860 5508 EMail: syl@etri.re.kr Yong-Jin Kim ETRI / PEC 161 Gajong-Dong, Yusong-Gu Daejon 305-350 Korea Phone: +82 42 860 6564 EMail: kimyj@etri.re.kr Jeong, Park, Lee, Kim Expires July 2002 [Page 8] INTERNET-DRAFT 1way Measurement using IPv6 Source Routing February 2002 Expiration date: July 2002 Jeong, Park, Lee, Kim Expires July 2002 [Page 9]