draft-ietf-ippm-2330-ipv6-06.txt   rfc8468.txt 
Network Working Group A. Morton Internet Engineering Task Force (IETF) A. Morton
Internet-Draft AT&T Labs Request for Comments: 8468 AT&T Labs
Updates: 2330 (if approved) J. Fabini Updates: 2330 J. Fabini
Intended status: Informational TU Wien Category: Informational TU Wien
Expires: January 1, 2019 N. Elkins ISSN: 2070-1721 N. Elkins
Inside Products, Inc. Inside Products, Inc.
M. Ackermann M. Ackermann
Blue Cross Blue Shield of Michigan Blue Cross Blue Shield of Michigan
V. Hegde V. Hegde
Consultant Consultant
June 30, 2018 November 2018
IPv6, IPv4 and Coexistence Updates for IPPM's Active Metric Framework IPv4, IPv6, and IPv4-IPv6 Coexistence:
draft-ietf-ippm-2330-ipv6-06 Updates for the IP Performance Metrics (IPPM) Framework
Abstract Abstract
This memo updates the IP Performance Metrics (IPPM) Framework RFC This memo updates the IP Performance Metrics (IPPM) framework defined
2330 with new considerations for measurement methodology and testing. by RFC 2330 with new considerations for measurement methodology and
It updates the definition of standard-formed packets in RFC 2330 to testing. It updates the definition of standard-formed packets to
include IPv6 packets, deprecates the definition of minimal IP packet, include IPv6 packets, deprecates the definition of minimal IP packet,
and augments distinguishing aspects of packets, referred to as Type-P and augments distinguishing aspects, referred to as Type-P, for test
for test packets in RFC 2330. This memo identifies that IPv4-IPv6 packets in RFC 2330. This memo identifies that IPv4-IPv6 coexistence
co-existence can challenge measurements within the scope of the IPPM can challenge measurements within the scope of the IPPM framework.
Framework. Example use cases include, but are not limited to Example use cases include, but are not limited to, IPv4-IPv6
IPv4-IPv6 translation, NAT, or protocol encapsulation. IPv6 header translation, NAT, and protocol encapsulation. IPv6 header
compression and use of IPv6 over Low-Power Wireless Area Networks compression and use of IPv6 over Low-Power Wireless Area Networks
(6LoWPAN) are considered and excluded from the standard-formed packet (6LoWPAN) are considered and excluded from the standard-formed packet
evaluation. evaluation.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14[RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This document is not an Internet Standards Track specification; it is
provisions of BCP 78 and BCP 79. published for informational purposes.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Not all documents
approved by the IESG are candidates for any level of Internet
Standard; see Section 2 of RFC 7841.
This Internet-Draft will expire on January 1, 2019. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8468.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
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publication of this document. Please review these documents publication of this document. Please review these documents
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Without obtaining an adequate license from the person(s) controlling Without obtaining an adequate license from the person(s) controlling
the copyright in such materials, this document may not be modified the copyright in such materials, this document may not be modified
outside the IETF Standards Process, and derivative works of it may outside the IETF Standards Process, and derivative works of it may
not be created outside the IETF Standards Process, except to format not be created outside the IETF Standards Process, except to format
it for publication as an RFC or to translate it into languages other it for publication as an RFC or to translate it into languages other
than English. than English.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 3
3. Packets of Type-P . . . . . . . . . . . . . . . . . . . . . . 3 3. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Standard-Formed Packets . . . . . . . . . . . . . . . . . . . 5 4. Packets of Type-P . . . . . . . . . . . . . . . . . . . . . . 4
5. NAT, IPv4-IPv6 Transition and Compression Techniques . . . . 8 5. Standard-Formed Packets . . . . . . . . . . . . . . . . . . . 5
6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 6. NAT, IPv4-IPv6 Transition, and Compression Techniques . . . . 9
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 7. Security Considerations . . . . . . . . . . . . . . . . . . . 10
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 10 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 10 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
9.1. Normative References . . . . . . . . . . . . . . . . . . 10 9.1. Normative References . . . . . . . . . . . . . . . . . . 11
9.2. Informative References . . . . . . . . . . . . . . . . . 13 9.2. Informative References . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
1. Introduction 1. Introduction
The IETF IP Performance Metrics (IPPM) working group first created a The IETF IP Performance Metrics (IPPM) working group first created a
framework for metric development in [RFC2330]. This framework has framework for metric development in [RFC2330]. This framework has
stood the test of time and enabled development of many fundamental stood the test of time and enabled development of many fundamental
metrics. It has been updated in the area of metric composition metrics. It has been updated in the area of metric composition
[RFC5835], and in several areas related to active stream measurement [RFC5835] and in several areas related to active stream measurement
of modern networks with reactive properties [RFC7312]. of modern networks with reactive properties [RFC7312].
The IPPM framework [RFC2330] recognized (in section 13) that many The IPPM framework [RFC2330] recognized (in Section 13) that many
aspects of IP packets can influence its processing during transfer aspects of an IP packet can influence its processing during transfer
across the network. across the network.
In Section 15 of [RFC2330], the notion of a "standard-formed" packet In Section 15 of [RFC2330], the notion of a "standard-formed" packet
is defined. However, the definition was never updated to include is defined. However, the definition was never expanded to include
IPv6, as the original authors originally desired to do. IPv6, even though the authors of [RFC2330] explicitly identified the
need for this update in Section 15: "the version field is 4 (later,
we will expand this to include 6)".
In particular, IPv6 Extension Headers and protocols which use IPv6 In particular, IPv6 Extension Headers and protocols that use IPv6
header compression are growing in use. This memo seeks to provide header compression are growing in use. This memo seeks to provide
the needed updates. the needed updates to the original definition in [RFC2330].
2. Scope 2. Requirements Language
The purpose of this memo is to expand the coverage of IPPM metrics to The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
include IPv6, and to highlight additional aspects of test packets and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
make them part of the IPPM performance metric framework. "OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. Scope
The purpose of this memo is to expand the coverage of IPPM to include
IPv6, highlight additional aspects of test packets, and make them
part of the IPPM framework.
The scope is to update key sections of [RFC2330], adding The scope is to update key sections of [RFC2330], adding
considerations that will aid the development of new measurement considerations that will aid the development of new measurement
methodologies intended for today's IP networks. Specifically, this methodologies intended for today's IP networks. Specifically, this
memo expands the Type-P examples in section 13 of [RFC2330] and memo expands the Type-P examples in Section 13 of [RFC2330] and
expands the definition (in section 15 of [RFC2330]) of a standard- expands the definition (in Section 15 of [RFC2330]) of a standard-
formed packet to include IPv6 header aspects and other features. formed packet to include IPv6 header aspects and other features.
Other topics in [RFC2330] which might be updated or augmented are Other topics in [RFC2330] that might be updated or augmented are
deferred to future work. This includes the topics of passive and deferred to future work. This includes the topics of passive and
various forms of hybrid active/passive measurements. various forms of hybrid active/passive measurements.
3. Packets of Type-P 4. Packets of Type-P
A fundamental property of many Internet metrics is that the measured A fundamental property of many Internet metrics is that the measured
value of the metric depends on characteristics of the IP packet(s) value of the metric depends on characteristics of the IP packet(s)
used to make the measurement. Potential influencing factors include used to make the measurement. Potential influencing factors include
IP header fields and their values, but also higher-layer protocol IP header fields and their values, as well as higher-layer protocol
headers and their values. Consider an IP-connectivity metric: one headers and their values. Consider an IP-connectivity metric: one
obtains different results depending on whether one is interested in obtains different results depending on whether one is interested in,
connectivity for packets destined for well-known TCP ports or for example, connectivity for packets destined for well-known TCP
unreserved UDP ports, or those with invalid IPv4 checksums, or those ports or unreserved UDP ports, those with invalid IPv4 checksums, or
with TTL or Hop Limit of 16, for example. In some circumstances those with TTL or Hop Limit of 16. In some circumstances, these
these distinctions will result in special treatment of packets in distinctions will result in special treatment of packets in
intermediate nodes and end systems (for example, if Diffserv intermediate nodes and end systems -- for example, if Diffserv
[RFC2474], ECN [RFC3168], Router Alert [RFC6398], Hop-by-hop [RFC2474], Explicit Congestion Notification (ECN) [RFC3168], Router
extensions [RFC7045], or Flow Labels [RFC6437] are used, or in the Alert [RFC6398], Hop-by-Hop extensions [RFC7045], or Flow Labels
presence of firewalls or RSVP reservations). [RFC6437] are used, or in the presence of firewalls or RSVP
reservations.
Because of this distinction, we introduce the generic notion of a Because of this distinction, we introduce the generic notion of a
"packet of Type-P", where in some contexts P will be explicitly "packet of Type-P", where in some contexts P will be explicitly
defined (i.e., exactly what type of packet we mean), partially defined (i.e., exactly what type of packet we mean), partially
defined (e.g., "with a payload of B octets"), or left generic. Thus defined (e.g., "with a payload of B octets"), or left generic. Thus,
we may talk about generic IP-Type-P-connectivity or more specific IP- we may talk about generic IP-Type-P-connectivity or more specific
port-HTTP-connectivity. Some metrics and methodologies may be IP-port-HTTP-connectivity. Some metrics and methodologies may be
fruitfully defined using generic Type-P definitions which are then fruitfully defined using generic Type-P definitions, which are then
made specific when performing actual measurements. made specific when performing actual measurements.
Whenever a metric's value depends on the type of the packets involved Whenever a metric's value depends on the type of the packets
in the metric, the metric's name will include either a specific type involved, the metric's name will include either a specific type or a
or a phrase such as "Type-P". Thus we will not define an "IP- phrase such as "Type-P". Thus, we will not define an
connectivity" metric but instead an "IP-Type-P-connectivity" metric "IP-connectivity" metric but instead an "IP-Type-P-connectivity"
and/or perhaps an "IP-port-HTTP-connectivity" metric. This naming metric and/or perhaps an "IP-port-HTTP-connectivity" metric. This
convention serves as an important reminder that one must be conscious naming convention serves as an important reminder that one must be
of the exact type of traffic being measured. conscious of the exact type of traffic being measured.
If the information constituting Type-P at the Source is found to have If the information constituting Type-P at the Source is found to have
changed at the Destination (or at a measurement point between the changed at the Destination (or at a measurement point between the
Source and Destination, as in [RFC5644]), then the modified values Source and Destination, as in [RFC5644]), then the modified values
MUST be noted and reported with the results. Some modifications MUST be noted and reported with the results. Some modifications
occur according to the conditions encountered in transit (such as occur according to the conditions encountered in transit (such as
congestion notification) or due to the requirements of segments of congestion notification) or due to the requirements of segments of
the Source to Destination path. For example, the packet length will the Source-to-Destination path. For example, the packet length will
change if IP headers are converted to the alternate version/address change if IP headers are converted to the alternate version/address
family, or if optional Extension Headers are added or removed. Even family or optional Extension Headers are added or removed. Even
header fields like TTL/Hop Limit that typically change in transit may header fields like TTL/Hop Limit that typically change in transit may
be relevant to specific tests. For example Neighbor Discovery be relevant to specific tests. For example, Neighbor Discovery
Protocol (NDP) [RFC4861] packets are transmitted with Hop Limit value Protocol (NDP) [RFC4861] packets are transmitted with the Hop Limit
set to 255, and the validity test specifies that the Hop Limit MUST value set to 255, and the validity test specifies that the Hop Limit
have a value of 255 at the receiver, too. So, while other tests may MUST have a value of 255 at the receiver, too. So, while other tests
intentionally exclude the TTL/Hop Limit value from their Type-P may intentionally exclude the TTL/Hop Limit value from their Type-P
definition, for this particular test the correct Hop Limit value is definition, for this particular test, the correct Hop Limit value is
of high relevance and MUST be part of the Type-P definition. of high relevance and MUST be part of the Type-P definition.
Local policies in intermediate nodes based on examination of IPv6 Local policies in intermediate nodes based on examination of IPv6
Extension Headers may affect measurement repeatability. If Extension Headers may affect measurement repeatability. If
intermediate nodes follow the recommendations of [RFC7045], intermediate nodes follow the recommendations of [RFC7045],
repeatability may be improved to some degree. repeatability may be improved to some degree.
A closely related note: it would be very useful to know if a given A closely related note: It would be very useful to know if a given
Internet component (like host, link, or path) treats equally a class Internet component (like a host, link, or path) treats equally a
C of different types of packets. If so, then any one of those types class C of different types of packets. If so, then any one of those
of packets can be used for subsequent measurement of the component. types of packets can be used for subsequent measurement of the
This suggests we devise a metric or suite of metrics that attempt to component. This suggests we should devise a metric or suite of
determine class C (a designation which has no relationship to address metrics that attempt to determine class C (a designation that has no
assignments, of course). relationship to address assignments, of course).
Load balancing over parallel paths is one particular example where Load-balancing over parallel paths is one particular example where
such a class C would be more complex to determine in IPPM such a class C would be more complex to determine in IPPM
measurements. Load balancers and routers often use flow identifiers, measurements. Load balancers and routers often use flow identifiers,
computed as hashes of (specific parts of) the packet header, for computed as hashes (of specific parts) of the packet header, for
deciding among the available parallel paths a packet will traverse. deciding among the available parallel paths a packet will traverse.
Packets with identical hashes are assigned to the same flow and Packets with identical hashes are assigned to the same flow and
forwarded to the same resource in the load balancer's (or router's) forwarded to the same resource in the load balancer's (or router's)
pool. The presence of a load balancer on the measurement path, as pool. The presence of a load balancer on the measurement path, as
well as the specific headers and fields that are used for the well as the specific headers and fields that are used for the
forwarding decision, are not known when measuring the path as a forwarding decision, are not known when measuring the path as a black
black-box. Potential assessment scenarios include the measurement of box. Potential assessment scenarios include the measurement of one
one of the parallel paths, and the measurement of all available of the parallel paths, and the measurement of all available parallel
parallel paths that the load balancer can use. Knowledge of a load paths that the load balancer can use. Therefore, knowledge of a load
balancer's flow definition (alternatively: its class C specific balancer's flow definition (alternatively, its class-C-specific
treatment in terms of header fields in scope of hash operations) is treatment in terms of header fields in scope of hash operations) is a
therefore a prerequisite for repeatable measurements. A path may prerequisite for repeatable measurements. A path may have more than
have more than one stage of load balancing, adding to class C one stage of load-balancing, adding to class C definition complexity.
definition complexity.
4. Standard-Formed Packets 5. Standard-Formed Packets
Unless otherwise stated, all metric definitions that concern IP Unless otherwise stated, all metric definitions that concern IP
packets include an implicit assumption that the packet is *standard- packets include an implicit assumption that the packet is standard-
formed*. A packet is standard-formed if it meets all of the following formed. A packet is standard-formed if it meets all of the following
REQUIRED criteria: REQUIRED criteria:
+ It includes a valid IP header: see below for version-specific + It includes a valid IP header. See below for version-specific
criteria. criteria.
+ It is not an IP fragment. + It is not an IP fragment.
+ The Source and Destination addresses correspond to the intended + The Source and Destination addresses correspond to the intended
Source and Destination, including Multicast Destination addresses. Source and Destination, including Multicast Destination addresses.
+ If a transport header is present, it contains a valid checksum and + If a transport header is present, it contains a valid checksum and
other valid fields. other valid fields.
For an IPv4 ([RFC0791] and updates) packet to be standard-formed, the For an IPv4 packet (as specified in [RFC791] and the RFCs that update
following additional criteria are REQUIRED: it) to be standard-formed, the following additional criteria are
REQUIRED:
o The version field is 4 o The version field is 4.
o The Internet Header Length (IHL) value is >= 5; the checksum is o The Internet Header Length (IHL) value is >= 5; the checksum is
correct. correct.
o Its total length as given in the IPv4 header corresponds to the o Its total length as given in the IPv4 header corresponds to the
size of the IPv4 header plus the size of the payload. size of the IPv4 header plus the size of the payload.
o Either the packet possesses sufficient TTL to travel from the o Either the packet possesses sufficient TTL to travel from the
Source to the Destination if the TTL is decremented by one at each Source to the Destination if the TTL is decremented by one at each
hop, or it possesses the maximum TTL of 255. hop or it possesses the maximum TTL of 255.
o It does not contain IP options unless explicitly noted. o It does not contain IP options unless explicitly noted.
For an IPv6 ([RFC8200] and updates) packet to be standard-formed, the For an IPv6 packet (as specified in [RFC8200] and any future updates)
following criteria are REQUIRED: to be standard-formed, the following criteria are REQUIRED:
o The version field is 6. o The version field is 6.
o Its total length corresponds to the size of the IPv6 header (40 o Its total length corresponds to the size of the IPv6 header (40
octets) plus the length of the payload as given in the IPv6 octets) plus the length of the payload as given in the IPv6
header. header.
o The payload length value for this packet (including Extension o The payload length value for this packet (including Extension
Headers) conforms to the IPv6 specifications. Headers) conforms to the IPv6 specifications.
o Either the packet possesses sufficient Hop Limit to travel from o Either the packet possesses sufficient Hop Limit to travel from
the Source to the Destination if the Hop Limit is decremented by the Source to the Destination if the Hop Limit is decremented by
one at each hop, or it possesses the maximum Hop Limit of 255. one at each hop or it possesses the maximum Hop Limit of 255.
o Either the packet does not contain IP Extension Headers, or it o Either the packet does not contain IP Extension Headers or it
contains the correct number and type of headers as specified in contains the correct number and type of headers as specified in
the packet, and the headers appear in the standard-conforming the packet and the headers appear in the standard-conforming order
order (Next Header). (Next Header).
o All parameters used in the header and Extension Headers are found o All parameters used in the header and Extension Headers are found
in the IANA Registry of Internet Protocol Version 6 (IPv6) in the "Internet Protocol Version 6 (IPv6) Parameters" registry
Parameters, specified in [IANA-6P]. specified in [IANA-6P].
Two mechanisms require some discussion in the context of standard- Two mechanisms require some discussion in the context of standard-
formed packets, namely IPv6 over Low-Power Wireless Area Networks formed packets, namely IPv6 over Low-Power Wireless Area Networks
(6LowPAN, [RFC4944]) and Robust Header Compression (ROHC, [RFC3095]). (6LowPAN) [RFC4944] and Robust Header Compression (ROHC) [RFC3095].
IPv6 over Low-Power Wireless Area Networks (6LowPAN), as defined in 6LowPAN, as defined in [RFC4944] and updated by [RFC6282] with header
[RFC4944] and updated by [RFC6282] with header compression and compression and [RFC6775] with neighbor discovery optimizations,
[RFC6775] with neighbor discovery optimizations, proposes solutions proposes solutions for using IPv6 in resource-constrained
for using IPv6 in resource-constrained environments. An adaptation environments. An adaptation layer enables the transfer of IPv6
layer enables the transfer of IPv6 packets over networks having a MTU packets over networks having an MTU smaller than the minimum IPv6
smaller than the minimum IPv6 MTU. Fragmentation and re-assembly of MTU. Fragmentation and reassembly of IPv6 packets, as well as the
IPv6 packets, as well as the resulting state that would be stored in resulting state that would be stored in intermediate nodes, poses
intermediate nodes, poses substantial challenges to measurements. substantial challenges to measurements. Likewise, ROHC operates
Likewise, ROHC operates statefully in compressing headers on statefully in compressing headers on subpaths, storing state in
subpaths, storing state in intermediate hosts. The modification of intermediate hosts. The modification of measurement packets' Type-P
measurement packets' Type-P by ROHC and 6LowPAN, as well as by ROHC and 6LowPAN requires substantial work, as do requirements
requirements with respect to the concept of standard-formed packets with respect to the concept of standard-formed packets for these two
for these two protocols requires substantial work. Because of these protocols. For these reasons, we consider ROHC and 6LowPAN packets
reasons we consider ROHC and 6LowPAN packets to be out of the scope to be out of the scope of the standard-formed packet evaluation.
for the standard-formed packet evaluation.
The topic of IPv6 Extension Headers brings current controversies into The topic of IPv6 Extension Headers brings current controversies into
focus as noted by [RFC6564] and [RFC7045]. However, measurement use focus, as noted by [RFC6564] and [RFC7045]. However, measurement use
cases in the context of the IPPM framework like in-situ OAM cases in the context of the IPPM framework, such as in situ OAM
[I-D.ietf-ippm-ioam-data] in enterprise environments can benefit from [IOAM-DATA] in enterprise environments, can benefit from inspection,
inspection, modification, addition or deletion of IPv6 extension modification, addition, or deletion of IPv6 extension headers in
headers in hosts along the measurement path. hosts along the measurement path.
[RFC8250] endorses the use of IPv6 Destination Option for measurement [RFC8250] endorses the use of the IPv6 Destination Option for
purposes, consistent with other approved IETF specifications. measurement purposes, consistent with other relevant and approved
IETF specifications.
The following additional considerations apply when IPv6 Extension The following additional considerations apply when IPv6 Extension
Headers are present: Headers are present:
o Extension Header inspection: Some intermediate nodes may inspect o Extension Header inspection: Some intermediate nodes may inspect
Extension Headers or the entire IPv6 packet while in transit. In Extension Headers or the entire IPv6 packet while in transit. In
exceptional cases, they may drop the packet or route via a sub- exceptional cases, they may drop the packet or route via a
optimal path, and measurements may be unreliable or unrepeatable. suboptimal path, and measurements may be unreliable or
The packet (if it arrives) may be standard-formed, with a unrepeatable. The packet (if it arrives) may be standard-formed,
corresponding Type-P. with a corresponding Type-P.
o Extension Header modification: In Hop-by-Hop headers, some TLV o Extension Header modification: In Hop-by-Hop headers, some TLV-
encoded options may be permitted to change at intermediate nodes encoded options may be permitted to change at intermediate nodes
while in transit. The resulting packet may be standard-formed, while in transit. The resulting packet may be standard-formed,
with a corresponding Type-P. with a corresponding Type-P.
o Extension Header insertion or deletion: Although such behavior is o Extension Header insertion or deletion: Although such behavior is
not endorsed by current standards, it is possible that Extension not endorsed by current standards, it is possible that Extension
Headers could be added to, or removed from the header chain. The Headers could be added to, or removed from, the header chain. The
resulting packet may be standard-formed, with a corresponding resulting packet may be standard-formed, with a corresponding
Type-P. This point simply encourages measurement system designers Type-P. This point simply encourages measurement system designers
to be prepared for the unexpected, and to notify users when such to be prepared for the unexpected and notify users when such
events occur. There are issues with Extension Header insertion events occur. There are issues with Extension Header insertion
and deletion of course, such as exceeding the path MTU due to and deletion, of course, such as exceeding the path MTU due to
insertion, etc. insertion, etc.
o A change in packet length (from the corresponding packet observed o A change in packet length (from the corresponding packet observed
at the Source) or header modification is a significant factor in at the Source) or header modification is a significant factor in
Internet measurement, and REQUIRES a new Type-P to be reported Internet measurement and REQUIRES a new Type-P to be reported with
with the test results. the test results.
It is further REQUIRED that if a packet is described as having a It is further REQUIRED that if a packet is described as having a
"length of B octets", then 0 <= B <= 65535; and if B is the payload "length of B octets", then 0 <= B <= 65535; and if B is the payload
length in octets, then B <= (65535-IP header size in octets, length in octets, then B <= (65535-IP header size in octets,
including any Extension Headers). The jumbograms defined in including any Extension Headers). The jumbograms defined in
[RFC2675] are not covered by the above length analysis, but if the [RFC2675] are not covered by the above length analysis, but if the
IPv6 Jumbogram Payload Hop-by-Hop Option Header is present, then a IPv6 Jumbogram Payload Hop-by-Hop Option Header is present, then a
packet with corresponding length MUST be considered standard-formed. packet with corresponding length MUST be considered standard-formed.
In practice, the path MTU will restrict the length of standard-formed In practice, the path MTU will restrict the length of standard-formed
packets that can successfully traverse the path. Path MTU Discovery packets that can successfully traverse the path. Path MTU Discovery
for IP version 6 (PMTUD, [RFC8201]) or Packetization Layer Path MTU for IP version 6 (PMTUD, [RFC8201]) or Packetization Layer Path MTU
Discovery (PLPMTUD, [RFC4821]) is recommended to prevent Discovery (PLPMTUD, [RFC4821]) is recommended to prevent
fragmentation. fragmentation.
So, for example, one might imagine defining an IP connectivity metric So, for example, one might imagine defining an IP-connectivity metric
as "IP-type-P-connectivity for standard-formed packets with the IP as "IP-Type-P-connectivity for standard-formed packets with the IP
Diffserv field set to 0", or, more succinctly, "IP-type- Diffserv field set to 0", or, more succinctly,
P-connectivity with the IP Diffserv Field set to 0", since standard- "IP-Type-P-connectivity with the IP Diffserv field set to 0", since
formed is already implied by convention. Changing the contents of a standard-formed is already implied by convention. Changing the
field, such as the Diffserv Code Point, ECN bits, or Flow Label may contents of a field, such as the Diffserv Code Point, ECN bits, or
have a profound affect on packet handling during transit, but does Flow Label may have a profound effect on packet handling during
not affect a packet's status as standard-formed. Likewise, the transit, but does not affect a packet's status as standard-formed.
addition, modification, or deletion of extension headers may change Likewise, the addition, modification, or deletion of extension
the handling of packets in transit hosts. headers may change the handling of packets in transit hosts.
[RFC2330] defines the "minimal IP packet from A to B" as a particular [RFC2330] defines the "minimal IP packet from A to B" as a particular
type of standard-formed packet often useful to consider. When type of standard-formed packet often useful to consider. When
defining IP metrics no packet smaller or simpler than this can be defining IP metrics, no packet smaller or simpler than this can be
transmitted over a correctly operating IP network. However, the transmitted over a correctly operating IP network. However, the
concept of the minimal IP packet has not been employed (since typical concept of the minimal IP packet has not been employed (since typical
active measurement systems employ a transport layer and a payload) active measurement systems employ a transport layer and a payload),
and its practical use is limited. Therefore, this memo deprecates and its practical use is limited. Therefore, this memo deprecates
the concept of the "minimal IP packet from A to B". the concept of the "minimal IP packet from A to B".
5. NAT, IPv4-IPv6 Transition and Compression Techniques 6. NAT, IPv4-IPv6 Transition, and Compression Techniques
This memo adds the key considerations for utilizing IPv6 in two This memo adds the key considerations for utilizing IPv6 in two
critical conventions of the IPPM Framework, namely packets of Type-P critical conventions of the IPPM framework, namely packets of Type-P
and standard-formed packets. The need for co-existence of IPv4 and and standard-formed packets. The need for coexistence of IPv4 and
IPv6 has originated transitioning standards like the Framework for IPv6 has originated transitioning standards like the framework for
IPv4/IPv6 Translation in [RFC6144] or IP/ICMP Translation Algorithms IPv4/IPv6 translation in [RFC6144] or the IP/ICMP translation
in [RFC7915] and [RFC7757]. algorithms in [RFC7915] and [RFC7757].
The definition and execution of measurements within the context of The definition and execution of measurements within the context of
the IPPM Framework is challenged whenever such translation mechanisms the IPPM framework is challenged whenever such translation mechanisms
are present along the measurement path. In particular use cases like are present along the measurement path. In use cases like IPv4-IPv6
IPv4-IPv6 translation, NAT, protocol encapsulation, or IPv6 header translation, NAT, protocol encapsulation, or IPv6 header compression
compression may result in modification of the measurement packet's may result in modification of the measurement packet's Type-P along
Type-P along the path. All these changes MUST be reported. Example the path. All these changes MUST be reported. Example consequences
consequences include, but are not limited to: include, but are not limited to:
o Modification or addition of headers or header field values in o Modification or addition of headers or header field values in
intermediate nodes. IPv4-IPv6 transitioning or IPv6 header intermediate nodes. IPv4-IPv6 transitioning or IPv6 header
compression mechanisms may result in changes of the measurement compression mechanisms may result in changes of the measurement
packets' Type-P, too. Consequently, hosts along the measurement packets' Type-P, too. Consequently, hosts along the measurement
path may treat packets differently because of the Type-P path may treat packets differently because of the Type-P
modification. Measurements at observation points along the path modification. Measurements at observation points along the path
may also need extra context to uniquely identify a packet. may also need extra context to uniquely identify a packet.
o Network Address Translators (NAT) on the path can have o Network Address Translators (NAT) on the path can have an
unpredictable impact on latency measurement (in terms of the unpredictable impact on latency measurement (in terms of the
amount of additional time added), and possibly other types of amount of additional time added) and possibly other types of
measurements. It is not usually possible to control this impact measurements. It is not usually possible to control this impact
(as testers may not have any control of the underlying network or as testers may not have any control of the underlying network or
middleboxes). There is a possibility that stateful NAT will lead middleboxes. There is a possibility that stateful NAT will lead
to unstable performance for a flow with specific Type-P, since to unstable performance for a flow with specific Type-P, since
state needs to be created for the first packet of a flow, and state needs to be created for the first packet of a flow and state
state may be lost later if the NAT runs out of resources. may be lost later if the NAT runs out of resources. However, this
However, this scenario does not invalidate the Type-P for testing scenario does not invalidate the Type-P for testing; for example,
- for example the purpose of a test might be exactly to quantify the purpose of a test might be exactly to quantify the NAT's
the NAT's impact on delay variation. The presence of NAT may mean impact on delay variation. The presence of NAT may mean that the
that the measured performance of Type-P will change between the measured performance of Type-P will change between the source and
source and the destination. This can cause an issue when the destination. This can cause an issue when attempting to
attempting to correlate measurements conducted on segments of the correlate measurements conducted on segments of the path that
path that include or exclude the NAT. Thus, it is a factor to be include or exclude the NAT. Thus, it is a factor to be aware of
aware of when conducting measurements. when conducting measurements.
o Variable delay due to internal state. One side effect of changes o Variable delay due to internal state. One side effect of changes
due to IPv4-IPv6 transitioning mechanisms is the variable delay due to IPv4-IPv6 transitioning mechanisms is the variable delay
that intermediate nodes spend for header modifications. Similar that intermediate nodes experience for header modifications.
to NAT the allocation of internal state and establishment of Similar to NAT, the allocation of internal state and establishment
context within intermediate nodes may cause variable delays, of context within intermediate nodes may cause variable delays,
depending on the measurement stream pattern and position of a depending on the measurement stream pattern and position of a
packet within the stream. For example the first packet in a packet within the stream. For example, the first packet in a
stream will typically trigger allocation of internal state in an stream will typically trigger allocation of internal state in an
intermediate IPv4-IPv6 transition host. Subsequent packets can intermediate IPv4-IPv6 transition host. Subsequent packets can
benefit from lower processing delay due to the existing internal benefit from lower processing delay due to the existing internal
state. However, large inter-packet delays in the measurement state. However, large interpacket delays in the measurement
stream may result in the intermediate host deleting the associated stream may result in the intermediate host deleting the associated
state and needing to re-establish it on arrival of another stream state and needing to re-establish it on arrival of another stream
packet. It is worth noting that this variable delay due to packet. It is worth noting that this variable delay due to
internal state allocation in intermediate nodes can be an explicit internal state allocation in intermediate nodes can be an explicit
use case for measurements. use case for measurements.
o Variable delay due to packet length. IPv4-IPv6 transitioning or o Variable delay due to packet length. IPv4-IPv6 transitioning or
header compression mechanisms modify the length of measurement header compression mechanisms modify the length of measurement
packets. The modification of the packet size may or may not packets. The modification of the packet size may or may not
change the way how the measurement path treats the packets. change how the measurement path treats the packets.
6. Security Considerations 7. Security Considerations
The security considerations that apply to any active measurement of The security considerations that apply to any active measurement of
live paths are relevant here as well. See [RFC4656] and [RFC5357]. live paths are relevant here as well. See [RFC4656] and [RFC5357].
When considering privacy of those involved in measurement or those When considering the privacy of those involved in measurement or
whose traffic is measured, the sensitive information available to those whose traffic is measured, the sensitive information available
potential observers is greatly reduced when using active techniques to potential observers is greatly reduced when using active
which are within this scope of work. Passive observations of user techniques that are within this scope of work. Passive observations
traffic for measurement purposes raise many privacy issues. We refer of user traffic for measurement purposes raise many privacy issues.
the reader to the privacy considerations described in the Large Scale We refer the reader to the privacy considerations described in the
Measurement of Broadband Performance (LMAP) Framework [RFC7594], Large Scale Measurement of Broadband Performance (LMAP) framework
which covers active and passive techniques. [RFC7594], which covers active and passive techniques.
7. IANA Considerations
This memo makes no requests of IANA.
8. Acknowledgements 8. IANA Considerations
The authors thank Brian Carpenter for identifying the lack of IPv6 This document has no IANA actions.
coverage in IPPM's Framework, and for listing additional
distinguishing factors for packets of Type-P. Both Brian and Fred
Baker discussed many of the interesting aspects of IPv6 with the co-
authors, leading to a more solid first draft: thank you both. Thanks
to Bill Jouris for an editorial pass through the pre-00 text. As we
completed our journey, Nevil Brownlee, Mike Heard, Spencer Dawkins,
Warren Kumari, and Suresh Krishnan all contributed useful
suggestions.
9. References 9. References
9.1. Normative References 9.1. Normative References
[RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, [RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791,
DOI 10.17487/RFC0791, September 1981, DOI 10.17487/RFC0791, September 1981,
<https://www.rfc-editor.org/info/rfc791>. <https://www.rfc-editor.org/info/rfc791>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis, [RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
"Framework for IP Performance Metrics", RFC 2330, "Framework for IP Performance Metrics", RFC 2330,
skipping to change at page 11, line 33 skipping to change at page 11, line 46
Wiebke, T., Yoshimura, T., and H. Zheng, "RObust Header Wiebke, T., Yoshimura, T., and H. Zheng, "RObust Header
Compression (ROHC): Framework and four profiles: RTP, UDP, Compression (ROHC): Framework and four profiles: RTP, UDP,
ESP, and uncompressed", RFC 3095, DOI 10.17487/RFC3095, ESP, and uncompressed", RFC 3095, DOI 10.17487/RFC3095,
July 2001, <https://www.rfc-editor.org/info/rfc3095>. July 2001, <https://www.rfc-editor.org/info/rfc3095>.
[RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition [RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition
of Explicit Congestion Notification (ECN) to IP", of Explicit Congestion Notification (ECN) to IP",
RFC 3168, DOI 10.17487/RFC3168, September 2001, RFC 3168, DOI 10.17487/RFC3168, September 2001,
<https://www.rfc-editor.org/info/rfc3168>. <https://www.rfc-editor.org/info/rfc3168>.
[RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and M. [RFC4656] Shalunov, S., Teitelbaum, B., Karp, A., Boote, J., and
Zekauskas, "A One-way Active Measurement Protocol M. Zekauskas, "A One-way Active Measurement Protocol
(OWAMP)", RFC 4656, DOI 10.17487/RFC4656, September 2006, (OWAMP)", RFC 4656, DOI 10.17487/RFC4656, September 2006,
<https://www.rfc-editor.org/info/rfc4656>. <https://www.rfc-editor.org/info/rfc4656>.
[RFC4821] Mathis, M. and J. Heffner, "Packetization Layer Path MTU [RFC4821] Mathis, M. and J. Heffner, "Packetization Layer Path MTU
Discovery", RFC 4821, DOI 10.17487/RFC4821, March 2007, Discovery", RFC 4821, DOI 10.17487/RFC4821, March 2007,
<https://www.rfc-editor.org/info/rfc4821>. <https://www.rfc-editor.org/info/rfc4821>.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, [RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
DOI 10.17487/RFC4861, September 2007, DOI 10.17487/RFC4861, September 2007,
<https://www.rfc-editor.org/info/rfc4861>. <https://www.rfc-editor.org/info/rfc4861>.
[RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler, [RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler,
"Transmission of IPv6 Packets over IEEE 802.15.4 "Transmission of IPv6 Packets over IEEE 802.15.4
Networks", RFC 4944, DOI 10.17487/RFC4944, September 2007, Networks", RFC 4944, DOI 10.17487/RFC4944, September 2007,
<https://www.rfc-editor.org/info/rfc4944>. <https://www.rfc-editor.org/info/rfc4944>.
[RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and J. [RFC5357] Hedayat, K., Krzanowski, R., Morton, A., Yum, K., and
Babiarz, "A Two-Way Active Measurement Protocol (TWAMP)", J. Babiarz, "A Two-Way Active Measurement Protocol
RFC 5357, DOI 10.17487/RFC5357, October 2008, (TWAMP)", RFC 5357, DOI 10.17487/RFC5357, October 2008,
<https://www.rfc-editor.org/info/rfc5357>. <https://www.rfc-editor.org/info/rfc5357>.
[RFC5644] Stephan, E., Liang, L., and A. Morton, "IP Performance [RFC5644] Stephan, E., Liang, L., and A. Morton, "IP Performance
Metrics (IPPM): Spatial and Multicast", RFC 5644, Metrics (IPPM): Spatial and Multicast", RFC 5644,
DOI 10.17487/RFC5644, October 2009, DOI 10.17487/RFC5644, October 2009,
<https://www.rfc-editor.org/info/rfc5644>. <https://www.rfc-editor.org/info/rfc5644>.
[RFC5835] Morton, A., Ed. and S. Van den Berghe, Ed., "Framework for [RFC5835] Morton, A., Ed. and S. Van den Berghe, Ed., "Framework for
Metric Composition", RFC 5835, DOI 10.17487/RFC5835, April Metric Composition", RFC 5835, DOI 10.17487/RFC5835, April
2010, <https://www.rfc-editor.org/info/rfc5835>. 2010, <https://www.rfc-editor.org/info/rfc5835>.
skipping to change at page 12, line 42 skipping to change at page 13, line 10
[RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, [RFC6437] Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme,
"IPv6 Flow Label Specification", RFC 6437, "IPv6 Flow Label Specification", RFC 6437,
DOI 10.17487/RFC6437, November 2011, DOI 10.17487/RFC6437, November 2011,
<https://www.rfc-editor.org/info/rfc6437>. <https://www.rfc-editor.org/info/rfc6437>.
[RFC6564] Krishnan, S., Woodyatt, J., Kline, E., Hoagland, J., and [RFC6564] Krishnan, S., Woodyatt, J., Kline, E., Hoagland, J., and
M. Bhatia, "A Uniform Format for IPv6 Extension Headers", M. Bhatia, "A Uniform Format for IPv6 Extension Headers",
RFC 6564, DOI 10.17487/RFC6564, April 2012, RFC 6564, DOI 10.17487/RFC6564, April 2012,
<https://www.rfc-editor.org/info/rfc6564>. <https://www.rfc-editor.org/info/rfc6564>.
[RFC6775] Shelby, Z., Ed., Chakrabarti, S., Nordmark, E., and C. [RFC6775] Shelby, Z., Ed., Chakrabarti, S., Nordmark, E., and
Bormann, "Neighbor Discovery Optimization for IPv6 over C. Bormann, "Neighbor Discovery Optimization for IPv6 over
Low-Power Wireless Personal Area Networks (6LoWPANs)", Low-Power Wireless Personal Area Networks (6LoWPANs)",
RFC 6775, DOI 10.17487/RFC6775, November 2012, RFC 6775, DOI 10.17487/RFC6775, November 2012,
<https://www.rfc-editor.org/info/rfc6775>. <https://www.rfc-editor.org/info/rfc6775>.
[RFC7045] Carpenter, B. and S. Jiang, "Transmission and Processing [RFC7045] Carpenter, B. and S. Jiang, "Transmission and Processing
of IPv6 Extension Headers", RFC 7045, of IPv6 Extension Headers", RFC 7045,
DOI 10.17487/RFC7045, December 2013, DOI 10.17487/RFC7045, December 2013,
<https://www.rfc-editor.org/info/rfc7045>. <https://www.rfc-editor.org/info/rfc7045>.
[RFC7312] Fabini, J. and A. Morton, "Advanced Stream and Sampling [RFC7312] Fabini, J. and A. Morton, "Advanced Stream and Sampling
skipping to change at page 13, line 41 skipping to change at page 14, line 12
DOI 10.17487/RFC8201, July 2017, DOI 10.17487/RFC8201, July 2017,
<https://www.rfc-editor.org/info/rfc8201>. <https://www.rfc-editor.org/info/rfc8201>.
[RFC8250] Elkins, N., Hamilton, R., and M. Ackermann, "IPv6 [RFC8250] Elkins, N., Hamilton, R., and M. Ackermann, "IPv6
Performance and Diagnostic Metrics (PDM) Destination Performance and Diagnostic Metrics (PDM) Destination
Option", RFC 8250, DOI 10.17487/RFC8250, September 2017, Option", RFC 8250, DOI 10.17487/RFC8250, September 2017,
<https://www.rfc-editor.org/info/rfc8250>. <https://www.rfc-editor.org/info/rfc8250>.
9.2. Informative References 9.2. Informative References
[I-D.ietf-ippm-ioam-data] [IANA-6P] IANA, "Internet Protocol Version 6 (IPv6) Parameters",
<https://www.iana.org/assignments/ipv6-parameters>.
[IOAM-DATA]
Brockners, F., Bhandari, S., Pignataro, C., Gredler, H., Brockners, F., Bhandari, S., Pignataro, C., Gredler, H.,
Leddy, J., Youell, S., Mizrahi, T., Mozes, D., Lapukhov, Leddy, J., Youell, S., Mizrahi, T., Mozes, D., Lapukhov,
P., Chang, R., daniel.bernier@bell.ca, d., and J. Lemon, P., Chang, R., daniel.bernier@bell.ca, d., and J. Lemon,
"Data Fields for In-situ OAM", draft-ietf-ippm-ioam- "Data Fields for In-situ OAM", Work in Progress,
data-03 (work in progress), June 2018. draft-ietf-ippm-ioam-data-03, June 2018.
[IANA-6P] IANA, "IANA Internet Protocol Version 6 (IPv6)
Parameters", Internet Assigned Numbers Authority
https://www.iana.org/assignments/ipv6-parameters, January
2018.
[RFC7594] Eardley, P., Morton, A., Bagnulo, M., Burbridge, T., [RFC7594] Eardley, P., Morton, A., Bagnulo, M., Burbridge, T.,
Aitken, P., and A. Akhter, "A Framework for Large-Scale Aitken, P., and A. Akhter, "A Framework for Large-Scale
Measurement of Broadband Performance (LMAP)", RFC 7594, Measurement of Broadband Performance (LMAP)", RFC 7594,
DOI 10.17487/RFC7594, September 2015, DOI 10.17487/RFC7594, September 2015,
<https://www.rfc-editor.org/info/rfc7594>. <https://www.rfc-editor.org/info/rfc7594>.
Acknowledgements
The authors thank Brian Carpenter for identifying the lack of IPv6
coverage in IPPM's framework and listing additional distinguishing
factors for packets of Type-P. Both Brian and Fred Baker discussed
many of the interesting aspects of IPv6 with the coauthors, leading
to a more solid first draft: thank you both. Thanks to Bill Jouris
for an editorial pass through the pre-00 text. As we completed our
journey, Nevil Brownlee, Mike Heard, Spencer Dawkins, Warren Kumari,
and Suresh Krishnan all contributed useful suggestions.
Authors' Addresses Authors' Addresses
Al Morton Al Morton
AT&T Labs AT&T Labs
200 Laurel Avenue South 200 Laurel Avenue South
Middletown, NJ 07748 Middletown, NJ 07748
USA United States of America
Phone: +1 732 420 1571 Phone: +1 732 420 1571
Fax: +1 732 368 1192 Fax: +1 732 368 1192
Email: acmorton@att.com Email: acm@researh.att.com
URI: http://home.comcast.net/~acmacm/
Joachim Fabini Joachim Fabini
TU Wien TU Wien
Gusshausstrasse 25/E389 Gusshausstrasse 25/E389
Vienna 1040 Vienna 1040
Austria Austria
Phone: +43 1 58801 38813 Phone: +43 1 58801 38813
Fax: +43 1 58801 38898 Fax: +43 1 58801 38898
Email: Joachim.Fabini@tuwien.ac.at Email: Joachim.Fabini@tuwien.ac.at
URI: http://www.tc.tuwien.ac.at/about-us/staff/joachim-fabini/ URI: http://www.tc.tuwien.ac.at/about-us/staff/joachim-fabini/
Nalini Elkins Nalini Elkins
Inside Products, Inc. Inside Products, Inc.
Carmel Valley, CA 93924 Carmel Valley, CA 93924
USA United States of America
Email: nalini.elkins@insidethestack.com Email: nalini.elkins@insidethestack.com
Michael S. Ackermann Michael S. Ackermann
Blue Cross Blue Shield of Michigan Blue Cross Blue Shield of Michigan
Email: mackermann@bcbsm.com Email: mackermann@bcbsm.com
Vinayak Hegde Vinayak Hegde
Consultant Consultant
Brahma Sun City, Wadgaon-Sheri Brahma Sun City, Wadgaon-Sheri
Pune, Maharashtra 411014 Pune, Maharashtra 411014
INDIA India
Phone: +91 9449834401 Phone: +91 9449834401
Email: vinayakh@gmail.com Email: vinayakh@gmail.com
URI: http://www.vinayakhegde.com URI: http://www.vinayakhegde.com
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