--- 1/draft-ietf-ippm-6man-pdm-option-11.txt 2017-06-08 07:14:20.446929636 -0700 +++ 2/draft-ietf-ippm-6man-pdm-option-12.txt 2017-06-08 07:14:20.514931249 -0700 @@ -1,21 +1,21 @@ INTERNET-DRAFT N. Elkins Inside Products R. Hamilton Chemical Abstracts Service M. Ackermann Intended Status: Proposed Standard BCBS Michigan -Expires: December 8, 2017 June 6, 2017 +Expires: December 10, 2017 June 8, 2017 IPv6 Performance and Diagnostic Metrics (PDM) Destination Option - draft-ietf-ippm-6man-pdm-option-11 + draft-ietf-ippm-6man-pdm-option-12 Abstract To assess performance problems, this document describes optional headers embedded in each packet that provide sequence numbers and timing information as a basis for measurements. Such measurements may be interpreted in real-time or after the fact. An implementation of the existing IPv6 Destination Options extension header, the Performance and Diagnostic Metrics (PDM) Destination Options extension header as well as the field limits, calculations, and usage @@ -59,68 +59,68 @@ described in the Simplified BSD License. Table of Contents 1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1 Terminology . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 Rationale for defined solution . . . . . . . . . . . . . . . 5 1.3 IPv6 Transition Technologies . . . . . . . . . . . . . . . . 6 2 Measurement Information Derived from PDM . . . . . . . . . . . . 6 2.1 Round-Trip Delay . . . . . . . . . . . . . . . . . . . . . . 6 - 2.2 Server Delay . . . . . . . . . . . . . . . . . . . . . . . . 8 - 3 Performance and Diagnostic Metrics Destination Option Layout . . 8 - 3.1 Destination Options Header . . . . . . . . . . . . . . . . . 8 - 3.2 Performance and Diagnostic Metrics Destination Option . . . 8 - 3.2.1 PDM Layout . . . . . . . . . . . . . . . . . . . . . . . 8 - 3.2.2 Base Unit for Time Measurement . . . . . . . . . . . . . 10 - 3.3 Header Placement . . . . . . . . . . . . . . . . . . . . . . 11 - 3.4 Header Placement Using IPSec ESP Mode . . . . . . . . . . . 11 - 3.4.1 Using ESP Transport Mode . . . . . . . . . . . . . . . . 11 - 3.4.2 Using ESP Tunnel Mode . . . . . . . . . . . . . . . . . 11 - 3.5 Implementation Considerations . . . . . . . . . . . . . . . 12 - 3.5.1 PDM Activation . . . . . . . . . . . . . . . . . . . . . 12 - 3.5.2 PDM Timestamps . . . . . . . . . . . . . . . . . . . . . 12 - 3.6 Dynamic Configuration Options . . . . . . . . . . . . . . . 12 - 3.7 Information Access and Storage . . . . . . . . . . . . . . . 12 - 4 Security Considerations . . . . . . . . . . . . . . . . . . . . 13 - 4.1 Resource Consumption and Resource Consumption Attacks . . . 13 - 4.2 Pervasive monitoring . . . . . . . . . . . . . . . . . . . . 13 - 4.3 PDM as a Covert Channel . . . . . . . . . . . . . . . . . . 14 - 4.4 Timing Attacks . . . . . . . . . . . . . . . . . . . . . . . 14 - 5 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 15 - 6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 - 6.1 Normative References . . . . . . . . . . . . . . . . . . . . 15 - 6.2 Informative References . . . . . . . . . . . . . . . . . . . 16 - Appendix A: Context for PDM . . . . . . . . . . . . . . . . . . . 16 - A.1 End User Quality of Service (QoS) . . . . . . . . . . . . . 16 - A.2 Need for a Packet Sequence Number (PSN) . . . . . . . . . . 16 - A.3 Rationale for Defined Solution . . . . . . . . . . . . . . . 17 - A.4 Use PDM with Other Headers . . . . . . . . . . . . . . . . . 17 - Appendix B : Timing Considerations . . . . . . . . . . . . . . . . 18 - B.1 Timing Differential Calculations . . . . . . . . . . . . . . 18 - B.2 Considerations of this time-differential representation . . 19 - B.2.1 Limitations with this encoding method . . . . . . . . . 19 - B.2.2 Loss of precision induced by timer value truncation . . 20 - Appendix C: Sample Packet Flows . . . . . . . . . . . . . . . . . 21 - C.1 PDM Flow - Simple Client Server . . . . . . . . . . . . . . 21 - C.1.1 Step 1 . . . . . . . . . . . . . . . . . . . . . . . . . 22 - C.1.2 Step 2 . . . . . . . . . . . . . . . . . . . . . . . . . 22 - C.1.3 Step 3 . . . . . . . . . . . . . . . . . . . . . . . . . 23 - C.1.4 Step 4 . . . . . . . . . . . . . . . . . . . . . . . . . 24 - C.1.5 Step 5 . . . . . . . . . . . . . . . . . . . . . . . . . 25 - C.2 Other Flows . . . . . . . . . . . . . . . . . . . . . . . . 25 - C.2.1 PDM Flow - One Way Traffic . . . . . . . . . . . . . . . 25 - C.2.2 PDM Flow - Multiple Send Traffic . . . . . . . . . . . . 27 - C.2.3 PDM Flow - Multiple Send with Errors . . . . . . . . . . 28 - Appendix D: Potential Overhead Considerations . . . . . . . . . . 29 - Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 30 - Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 31 + 2.2 Server Delay . . . . . . . . . . . . . . . . . . . . . . . . 7 + 3 Performance and Diagnostic Metrics Destination Option Layout . . 7 + 3.1 Destination Options Header . . . . . . . . . . . . . . . . . 7 + 3.2 Performance and Diagnostic Metrics Destination Option . . . 7 + 3.2.1 PDM Layout . . . . . . . . . . . . . . . . . . . . . . . 7 + 3.2.2 Base Unit for Time Measurement . . . . . . . . . . . . . 9 + 3.3 Header Placement . . . . . . . . . . . . . . . . . . . . . . 10 + 3.4 Header Placement Using IPSec ESP Mode . . . . . . . . . . . 10 + 3.4.1 Using ESP Transport Mode . . . . . . . . . . . . . . . . 10 + 3.4.2 Using ESP Tunnel Mode . . . . . . . . . . . . . . . . . 10 + 3.5 Implementation Considerations . . . . . . . . . . . . . . . 11 + 3.5.1 PDM Activation . . . . . . . . . . . . . . . . . . . . . 11 + 3.5.2 PDM Timestamps . . . . . . . . . . . . . . . . . . . . . 11 + 3.6 Dynamic Configuration Options . . . . . . . . . . . . . . . 11 + 3.7 Information Access and Storage . . . . . . . . . . . . . . . 11 + 4 Security Considerations . . . . . . . . . . . . . . . . . . . . 12 + 4.1 Resource Consumption and Resource Consumption Attacks . . . 12 + 4.2 Pervasive monitoring . . . . . . . . . . . . . . . . . . . . 12 + 4.3 PDM as a Covert Channel . . . . . . . . . . . . . . . . . . 13 + 4.4 Timing Attacks . . . . . . . . . . . . . . . . . . . . . . . 13 + 5 IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 14 + 6 References . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 + 6.1 Normative References . . . . . . . . . . . . . . . . . . . . 14 + 6.2 Informative References . . . . . . . . . . . . . . . . . . . 15 + Appendix A: Context for PDM . . . . . . . . . . . . . . . . . . . 15 + A.1 End User Quality of Service (QoS) . . . . . . . . . . . . . 15 + A.2 Need for a Packet Sequence Number (PSN) . . . . . . . . . . 15 + A.3 Rationale for Defined Solution . . . . . . . . . . . . . . . 16 + A.4 Use PDM with Other Headers . . . . . . . . . . . . . . . . . 16 + Appendix B : Timing Considerations . . . . . . . . . . . . . . . . 17 + B.1 Timing Differential Calculations . . . . . . . . . . . . . . 17 + B.2 Considerations of this time-differential representation . . 18 + B.2.1 Limitations with this encoding method . . . . . . . . . 18 + B.2.2 Loss of precision induced by timer value truncation . . 19 + Appendix C: Sample Packet Flows . . . . . . . . . . . . . . . . . 20 + C.1 PDM Flow - Simple Client Server . . . . . . . . . . . . . . 20 + C.1.1 Step 1 . . . . . . . . . . . . . . . . . . . . . . . . . 21 + C.1.2 Step 2 . . . . . . . . . . . . . . . . . . . . . . . . . 21 + C.1.3 Step 3 . . . . . . . . . . . . . . . . . . . . . . . . . 22 + C.1.4 Step 4 . . . . . . . . . . . . . . . . . . . . . . . . . 23 + C.1.5 Step 5 . . . . . . . . . . . . . . . . . . . . . . . . . 24 + C.2 Other Flows . . . . . . . . . . . . . . . . . . . . . . . . 24 + C.2.1 PDM Flow - One Way Traffic . . . . . . . . . . . . . . . 24 + C.2.2 PDM Flow - Multiple Send Traffic . . . . . . . . . . . . 26 + C.2.3 PDM Flow - Multiple Send with Errors . . . . . . . . . . 27 + Appendix D: Potential Overhead Considerations . . . . . . . . . . 28 + Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 29 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 30 1 Background To assess performance problems, measurements based on optional sequence numbers and timing may be embedded in each packet. Such measurements may be interpreted in real-time or after the fact. As defined in RFC2460 [RFC2460], destination options are carried by the IPv6 Destination Options extension header. Destination options include optional information that need be examined only by the IPv6 @@ -244,21 +243,26 @@ The IPv6 Performance and Diagnostic Metrics Destination Option (PDM) contains the following fields: SCALEDTLR: Scale for Delta Time Last Received SCALEDTLS: Scale for Delta Time Last Sent PSNTP : Packet Sequence Number This Packet PSNLR : Packet Sequence Number Last Received DELTATLR : Delta Time Last Received DELTATLS : Delta Time Last Sent - The alignment for PDM is per RFC2460 [RFC2460]. + PDM has alignment requirements. Following the convention in IPv6, + these options are aligned in a packet so that multi-octet values + within the Option Data field of each option fall on natural + boundaries (i.e., fields of width n octets are placed at an integer + multiple of n octets from the start of the header, for n = 1, 2, 4, + or 8) [RFC2460]. The PDM destination option is encoded in type-length-value (TLV) format 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Option Type | Option Length | ScaleDTLR | ScaleDTLS | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | PSN This Packet | PSN Last Received |