wdiff draft-wu-pce-dns-pce-discovery-01.txt draft-wu-pce-dns-pce-discovery-02.txt

PCE Working Group Q. Wu
Internet-Draft D. Dhody
Intended status: Standards Track Huawei
Expires: January 16, February 13, 2014 July 15, D. King
Old Dog Consulting
D. Lopez
Telefonica I+D
August 12, 2013

Path Computation Element (PCE) Discovery using Domain Name System(DNS)
draft-wu-pce-dns-pce-discovery-01
draft-wu-pce-dns-pce-discovery-02

Abstract

Discovery of the Path Computation Element (PCE) within an IGP area or
routing domain is possible using OSPF [RFC5088] and IS-IS [RFC5089].
However, in some deployment scenarios PCEs may not wish, or be able,
to participate within the IGP process,therefore process, therefore it would be
beneficial for the Path Computation Client (PCC) (or other PCEs) to
discover PCEs via an alternative mechanism to those proposed in
[RFC5088] and [RFC5089].

This document specifies the requirements, use cases, procedures and
extensions to support discovery via DNS for PCE.

Status of this Memo

This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.

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 http://datatracker.ietf.org/drafts/current/.

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."

This Internet-Draft will expire on January 16, February 13, 2014.

This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
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carefully, as they describe your rights and restrictions with respect
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Table of Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Requirements . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions used in this document . . . . . . . . . . . . . . 4 5
3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . 5 6
3.1. Load Sharing of Path Computation Requests Outside the Routing Domain . . . . . . . . 5
3.2. Network Address Translation Gateway . . . . . . . . 6
3.2. Query-Response v/s Advertisement . . . 5
3.3. Multiple-Provider Domains . . . . . . . . . . 7
3.3. Network Address Translation Gateway . . . . . . 5
3.4. Multiple PCE Servers . . . . . 7
4. Other Considerations . . . . . . . . . . . . . . 6
3.5. End to End Path Computation . . . . . . . 8
4.1. Load Sharing of Path Computation Requests . . . . . . . . 6
4. 8
5. Discovering a Path Computation Element . . . . . . . . . . . . 7
4.1. 9
5.1. Determining the PCE Service and transport protocol . . . . 8
4.2. 10
5.2. Determining the IP Address of the PCE . . . . . . . . . . 8
4.3. 10
5.3. Determining path computation scope,the scope,capability,the PCE
domains and Neighbor PCE domains . . . . . . . . . . . . . 11
5.4. Relationship between PCE-Domain and DNS Domain-Name . . . . . . 9
5. 12
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
6. 13
7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
7. 14
8. Acknowledges . . . . . . . . . . . . . . . . . . . . . . . . . 13
8. 15
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. 16
9.1. Normative References . . . . . . . . . . . . . . . . . . . 14
8.2. 16
9.2. Informative References . . . . . . . . . . . . . . . . . . 15 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16 18

1. Introduction

The Path Computation Element Communication Protocol (PCEP) is a
transaction-based protocol carried over TCP[RFC4655]. TCP [RFC4655]. In order to
be able to direct path computation requests to the Path Computation
Element (PCE), a Path Computation Client (PCC) (or other PCEs) needs
to know the location and capability of a PCE.

In a network where an IGP is used and where the PCE participates in
the IGP, discovery mechanisms exist for PCC (or PCE) to learn the
identity and capability of each PCE. [RFC5088] defines a PCE
Discovery (PCED) TLV carried in an OSPF Router LSA. Similarly,
[RFC5089] defines the PCED sub-TLV for use in PCE Discovery using
IS-IS. Scope of the advertisement is limited to IGP area/level or
Autonomous System (AS).

However in certain scenarios not all PCEs will participate in the IGP
instance, section 3 (Motivation) outlines a number of use cases. In
these cases, current PCE Discovery mechanisms are therefore not
appropriate and another PCE discovery function would be required.

This document describes PCE discovery via DNS. The mechanism with
which DNS comes to know about the PCE and its capability is out of
scope of this document.

1.1. Terminology

The following terminology is used in this document.

Domain: As per [RFC4655], any collection of network elements within
a common sphere of address management or path computational
responsibility. Examples of domains include Interior Gateway
Protocol (IGP) areas and Autonomous Systems (ASs).

Domain-Name: TBD.

1.2. Requirements

As described in [RFC4674], the PCE Discovery information should at
least be composed of:

o The PCE location: an IPv4 and/or IPv6 address that is used to
reach the PCE. It is RECOMMENDED to use an address that is always
reachable if there is any connectivity to the PCE;

o The PCE path computation scope (i.e., intra-layer, inter-area,
inter-AS, or inter-layer);

o The set of one or more PCE-Domain(s) into which the PCE has
visibility and for which the PCE can compute paths;

o The set of zero, one, or more neighbor PCE-Domain(s) toward which
the PCE can compute paths;

that allows PCCs to select appropriate PCEs:

This document specifies an extension to DNS for the above PCE
information discovery, which is complements the existing discovery
mechanism.

2. Conventions used in this document

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 [RFC2119].

3. Motivation

This section discusses in more detail the motivation and use cases
for an alternative DNS based PCE discovery mechanism.

3.1. Load Sharing of Path Computation Requests

Multiple PCE servers can be present in a single network domain for
redundancy. However load balance decision is made by PCC,it doesn't
enable real load balance across Outside the PCE servers if PCC still tries
PCE one by one and PCE doesn't indicate the load status to the PCC.

Inherent DNS based load balancing may be used for inbound load
balancing and implemented at Routing Domain

When the application level in both servers
and clients. Multiple host IP addresses are configured in DNS for a
single host server name. Also DNS is query-response based mechanism
and capable of automatically detecting and reacting to errors. These
allow you to provide load balancing across two separate Systems and
facilitate PCE system failover and recovery.

Comparing with advertisement based PCE discovery
[RFC5088][RFC5089],it can mitigate flooding issue (see section 3.2 of
[RFC5088])and avoid unwanted traffic and reduce is a large amount of
unnecessary advertisement, especially when PCE information needs
frequent changes.

3.2. Network Address Translation router participating in the Interior Gateway

PCEP uses TCP as
Protocol (IGP), or even a server participating passively in the transport [RFC5440]. To secure TCP connection
that underly IGP,
with all PCEP sessions, TLS can be used besides using TCP-MD5.
When NAT gateway is speakers in place, a TCP or TCP/TLS connection can be
opened by ICE for the purpose same routing domain, a simple and
efficient way to announce PCEs consists of connectivity checks. However using IGP flooding.

But the
TCP connection cannot be established existing mechanism does not work in cases where one of the agents
is behind a NAT with connection-dependent filtering properties
[RFC5382]. Therefore IGP discovery is limited within an IGP following situations:

Inter-AS: Per domain
and cannot be used in this case.

3.3. Multiple-Provider Domains path computation mechanism [RFC5152] or
Backward recursive path computation (BRPC) [RFC5441] MAY be used
by cooperating PCEs to compute inter-domain path. In which case
these cooperating PCEs should be known to other PCEs. In case of
inter-AS where the PCE PCEs do not participate in a common IGP, the
existing IGP discovery mechanism cannot be used to discover
inter-AS PCE.

Also in the case

Hierarchy of multiple ASes within different service provider
networks, the PCE: The H-PCE [RFC6805] architecture does not require
disclosure of internals of a child domain to the parent PCE. It
may be necessary for a third party to manage the parent PCEs
according to commercial and policy agreements from each of the
participating service providers. providers [PCE-QUESTION]. [RFC6805]
specifies that a child PCE must be configured with the address of
its parent PCE in order for it to interact with its parent PCE.
However handling changes in parent PCE identities and coping with
failure events would be an issue for a configured system. There
is no scope for parent PCEs to advertise their presence,
however there is potential for directory systems (such as DNS
[RFC4848] as used in presence to child
PCEs when they are not a part of the ALTO discovery function [I-D.ietf-alto-
server-discovery]).

3.4. Multiple PCE Servers

In some cases, each network domain may have multiple PCE server, only
one main PCE sever is responsible for Establish topology database same routing domain.

BGP: [I.D.draft-ietf-idr-ls-distribution] describes a mechanism by
participating in OSPF/ISIS
which links state and traffic engineering information can be
collected from networks and shared with external components using
the BGP routing protocol, protocol. An external PCE MAY use this mechanism
to populate its TED and not take part in the other same IGP routing
domain.

NMS/OSS: PCE server
gains MAY gain the knowledge of Topology information either
from TED maintained by some management system (e.g.,NMS/OSS) and not take part in
the main PCE server or same routing domain. Also note that in some case PCC may not
be a router and instead be a management system(e.g.,NMS/OSS). In such
cases, system like NMS and may
not be able to discover PCE via IGP discovery.

3.2. Query-Response v/s Advertisement

Advertisement based IGP PCE discovery [RFC5088] and [RFC5089] floods
the PCE information to an area, a subset of areas or to a full
routing domain. By the very nature of flooding and advertisements it is desirable
generates unwanted traffic and may lead to use unnecessary advertisement,
especially when PCE information needs frequent changes.

DNS is a query-response based mechanism mechanism, a client (say PCC) can use
DNS to discover PCE.

3.5. End to End Path Computation

To compute end to end paths across domains, a PCE has only when it needs it and does not require any
other node in the following
limitations:

o Within network to be involved.

Incase of Intermittent PCEP session, where PCEP sessions are
systematically open and closed for each PCEP request, a single area, DNS based
query-response mechanism is more suitable. One may utilize DNS based
load-balancing and recovery functions.

3.3. Network Address Translation Gateway

PCEP uses TCP as the transport [RFC5440]. To secure TCP connection
that underlay PCEP sessions, TLS can be used besides using TCP-MD5
[RFC2385] and TCP-AUTH [RFC5295]. When PCC and PCE support TCP-MD5
or TCP-AUTH while NAT does not, TCP connection establishment fails.
When NAT gateway is in presence, a TCP or TCP/TLS connection can not offers enhanced
computational power be
opened by Interactive Connectivity Establishment (ICE) [RFC5245] for end to end path computation,e.g.,
coordination
the purpose of computation across connectivity checks. However the whole area.

o A single router participating TCP connection
cannot be established in IGP area lacks visibility cases where one of
complete topology the peers is behind a NAT
with its own TED.

Per connection-dependent filtering properties [RFC5382]. Therefore
IGP discovery is limited within an IGP domain path computation mechanism[RFC5152]can and cannot be used to compute
end to end path, however it may lead to sub-optimal paths or result in no end to end path to be found when the
this case.

4. Other Considerations

4.1. Load Sharing of Path Computation Requests

Multiple PCE only has visibility
into the IGP area it serves. This issue servers can be resolved when one
powerful PCE is responsible present in a single network domain for
redundancy. DNS supports inherent load balancing where multiple areas,i.e., PCE sits PCEs
(with different IP addresses) are known in one
area it serves and also can get access to topology information
provided by DNS for a single PCE
server in other IGP area using BGP. name and are hidden from the PCC.

In such case, an IGP advertisement based PCE discovery, one learns of all the
PCEs and it
will be desirable is the job of the PCC to use do load-balancing.

A DNS based load-balancing mechanism works well in case of
Intermittent PCEP sessions and request are load-balanced among PCEs
similar to discover those PCE
that has visibility to multiple areas.

4. HTTP request without any complexity at the client.

5. Discovering a Path Computation Element

The Dynamic Delegation Discovery System (DDDS) [RFC3401] is used to
implement lazy binding of strings to data, in order to support
dynamically configured delegation systems. The DDDS functions by
mapping some unique string to data stored within a DDDS database by
iteratively applying string transformation rules until a terminal
condition is reached. When DDDS uses DNS as a distributed database
of rules, these rules are encoded using the Naming Authority Pointer
(NAPTR) Resource Record (RR). One of these rules is the First Well
Known Rule, which says where the process starts.

In current specifications, the First Well Known Rule in a DDDS
application [RFC3403] is assumed to be fixed, i.e., the domain in the
tree where the lookups are to be routed to, is known. This document
proposes the input to the First Well Known Rule to be dynamic, based
on the search path the resolver discovers or is configured to use.

The search path of the resolver can either be pre-configured, or
discovered using DHCP.

When the PCC or other PCEs needs to discover PCEs in the domain into
which the PCEP speaker has visibility (e.g.,local domain), the input
to the First Well Known Rule MUST be the domain the PCC knows, which
is assumed to be pre- configured pre-configured in the PCC or discovered using DHCP.

When the PCC needs to discover PCE in the other domain (e.g., AS,
Parent PCE in the parent domain)into which the PCC has no visibility,
it SHOULD know the domain name of that domain and use DHCP to
discover IP address of the PCE in that domain that provides path
computation service along with some PCE location information useful
to a PCC for PCE selection, and contact it directly. In some
instances, the discovery may result in a per protocol/application
list of domain names that are then used as starting points for the
subsequent NAPTR lookups. If neither the IP address or nor other PCE
location information can be discovered with the above procedure, the
PCC MAY request a domain search list, as described in [RFC3397] and
[RFC3646], and use it as input to the DDDS application.

When the PCC does not find valid domain names using the procedures
above, it MUST stop the attempt to discover any PCE.

The dynamic rule described above SHOULD NOT be used for discovering
services other than Path computation services described in this
document, unless stated otherwise by a future specification.

The procedures defined here result in an IP address, PCE domain,
neighboring PCE domain and PCE Computation Scope where the PCC can
contact the PCE that hosts the service the PCC is looking for.

4.1.

5.1. Determining the PCE Service and transport protocol

The PCC should know the service identifier for the Path Computation
Discovery service. The service identifier for the Path Computation
Discovery service is defined as "PCED", The PCE supporting "PCED"
service MUST support only TCP as transport, as described in
[RFC5440].

The services relevant for the task of transport protocol selection
are those with NAPTR service fields with values "ID+M2X", where ID is
the service identifier defined in the previous section, and X is a
letter that corresponds to a transport protocol supported by the
domain. This specification only defines M2T for TCP. This document
also establishes an IANA registry for mappings of NAPTR service name
to transport protocol.

These NAPTR [RFC3403] records provide a mapping from a domain to the
SRV [RFC2782] record for contacting a PCE with the specific transport
protocol in the NAPTR services field. The resource record MUST
contain an empty regular expression and a replacement value, which
indicates the domain name where the SRV record for that particular
transport protocol can be found. As per [RFC3403], the client
discards any records whose services fields are not applicable.

The PCC MUST discard any service fields that identify a resolution
service whose value is not "M2T", for values of T that indicate TCP
transport protocols supported by the client. The NAPTR processing as
described in RFC 3403 will result in the discovery of the most
preferred transport protocol of the PCE that is supported by the
client, as well as an SRV record for the PCE.

4.2.

5.2. Determining the IP Address of the PCE

As an example, consider a client that wishes to find "PCED" PCED service in
the example.com domain. The client performs a NAPTR query for that
domain, and the following NAPTR records are returned:

Order Pref Flags Service Regexp Replacement
IN NAPTR 50 50 "s" "PCED" ""
_PCED._tcp.example.com
IN NAPTR 90 50 "s" "PCED+M2T" ""
_PCED._tcp.example.com

This indicates that the domain does have a PCE providing Path
Computation services over TCP, in that order of preference. Since
the client only supports TCP, TCP will be used, targeted to a host
determined by an SRV lookup of _PCED._tcp.example.com. That lookup
would return:

;; Priority Weight Port Target
IN SRV 0 1 XXXX server1.example.com
IN SRV 0 2 XXXX server2.example.com

where XXXX represents the port number at which the service is
reachable.

Note that the regexp field in the NAPTR example above is empty. The
regexp field MUST NOT be used when discovering path computation
services, as its usage can be complex and error prone. Also, the
discovery of the path computation service does not require the
flexibility provided by this field over a static target present in
the TARGET field.

If the client is already configured with the information about which
transport protocol is used for a path computation service in a
particular domain, it can directly perform an SRV query for that
specific transport using the service identifier of the path
computation Service. For example, if the client knows that it should
be using TCP for path computation service, it can perform a SRV query
directly for_PCED._tcp.example.com.

Once the server providing the desired service and the transport
protocol has been determined, the next step is to determine the IP
address.

According to the specification of SRV RRs in [RFC2782], the TARGET
field is a fully qualified domain name (FQDN) that MUST have one or
more address records; the FQDN must not be an alias, i.e., there MUST
NOT be a CNAME or DNAME RR at this name. Unless the SRV DNS query
already has reported a sufficient number of these address records in
the Additional Data section of the DNS response (as recommended by
[RFC2782]), the PCC needs to perform A and/or AAAA record lookup(s)
of the domain name, as appropriate. The result will be a list of IP
addresses, each of which can be contacted using the transport
protocol determined previously.

4.3.

5.3. Determining path computation scope,the scope,capability,the PCE domains and
Neighbor PCE domains

DNS servers MAY use DNS TXT record to give additional information
about PCE service and add new RRsets TXT record to the additional information
section that are relevant to the answer and have the same
authenticity as the data (the IP Address (Generally this will be made up of the PCE)in A and SRV
records)in the answer section. RRsets include The additional information includes
path computation scope, capability, the PCE domains and Neighbor PCE
domains associated with the PCE. the PCC MAY inspect those Additional
Information section and be capable of handling responses from
nameservers that never fill in the Additional Information part of a
response.

5.4. Relationship between PCE-Domain and DNS Domain-Name

As per [RFC4655], PCE-Domain is a collection of network elements
within a common sphere of address management or path computational
responsibility. Examples of PCE-domains include Interior Gateway
Protocol (IGP) areas and Autonomous Systems (ASs). The DNS domain-
name should have a mechanism to link the IGP area or AS to the DNS
namespace.

Editors Note - To be discussed further

6. IANA Considerations

The usage of NAPTR records described here requires well-known values
for the service fields for the transport supported by Path
Computation Services. The table of mappings from service field
values to transport protocols is to be maintained by IANA.

The registration in the RFC MUST include the following information:

Service Field: The service field being registered.

Protocol: The specific transport protocol associated with that
service field. This MUST include the name and acronym for the
protocol, along with reference to a document that describes the
transport protocol.

Name and Contact Information: The name, address, email address,
and telephone number for the person performing the registration.

The following values have been placed into the registry:

Service Fields Protocol
PCED+M2T TCP

New Service Fields are to be added via Standards Action as defined in
[RFC5226].

IANA is also requested to register PCED as service name in the
Protocol and Service Names registry.

7. Security Considerations

It is believed that this proposed DNS extension introduces no new
security considerations (i.e., A list of known threats to services
using DNS) beyond those described in [RFC3833]. For most of those
identified threats, the DNS Security Extensions [RFC4033] does
provide protection. It is therefore recommended to consider the
usage of DNSSEC [RFC4033] and the aspects of DNSSEC Operational
Practices [RFC4641] [RFC6781] when deploying Path Computation Services.

In deployments where DNSSEC usage is not feasible, measures should be
taken to protect against forged DNS responses and cache poisoning as
much as possible. Efforts in this direction are documented in
[RFC5452].

Where inputs to the procedure described in this document are fed via
DHCP, DHCP vulnerabilities can also cause issues. For instance, the
inability to authenticate DHCP discovery results may lead to the Path
Computation service results also being incorrect, even if the DNS
process was secured.

8. Acknowledges

The author would like to thank Claire Bi,Ning Kong and Kong, Liang Xia Xia,
Stephane Bortzmeyer,Yi Yang, Ted Lemon and Adrian Farrel for their
review and comments that help improvement to this document.

9. References

8.1.

9.1. Normative References

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", March 1997.

[RFC2782] Gulbrandsen, A., "A DNS RR for specifying the location of
services (DNS SRV)", RFC 2782, February 2000.

[RFC3397] Aboba, B., "Dynamic Host Configuration Protocol (DHCP)
Domain Search Option", RFC 3397, November 2002.

[RFC3403] Mealling, M., "Dynamic Delegation Discovery System (DDDS)
Part Three: The Domain Name System (DNS) Database",
RFC 3403, October 2002.

[RFC3646] Droms, R., "DNS Configuration options for Dynamic Host
Configuration Protocol for IPv6 (DHCPv6)", RFC 3646,
December 2003.

[RFC4033] Arends, R., "DNS Security Introduction and Requirements",
RFC 4033, March 2005.

[RFC4641] Kolkman, O., "DNSSEC Operational Practices",

[RFC4655] Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
Element (PCE)-Based Architecture", RFC 4641,
September 4655, August 2006.

[RFC4674] Droms, R., "Requirements for Path Computation Element
(PCE) Discovery", RFC 4674, December 2003.

[RFC4848] Daigle, D., "Domain-Based Application Service Location
Using URIs and the Dynamic Delegation Discovery Service
(DDDS)", RFC 4848, April 2007.

[RFC5226] Narten, T., "Guidelines for Writing an IANA Considerations
Section in RFCs", RFC 5226, May 2008.

[RFC5440] Le Roux, JL., "Path Computation Element (PCE)
Communication Protocol (PCEP)", RFC 5440, April 2007.

[RFC6781] Kolkman, O., Mekking, W., and R. Gieben, "DNSSEC
Operational Practices, Version 2", RFC 6781,
December 2012.

[RFC6805] King, D. and A. Farrel, "The Application of the Path
Computation Element Architecture to the Determination of a
Sequence of Domains in MPLS and GMPLS", RFC 6805,
November 2012.

8.2.

9.2. Informative References

[ALTO] Kiesel, S., "ALTO Server Discovery",
ID draft-ietf-alto-server-discovery-08, March 2013.

[BGP-LS] Gredler, H., "North-Bound Distribution of Link-State and
TE Information using BGP",
ID draft-ietf-idr-ls-distribution-03, May 2013.

[PCE-QUESTION]
Farrel, A., "Unanswered Questions in the Path Computation
Element Architecture",
ID http://tools.ietf.org/html/draft-ietf-pce-questions-00,
July 2013.

[RFC2385] Heffernan, A., "Protection of BGP Sessions via the TCP MD5
Signature Option", RFC 2385, August 1998.

[RFC3401] Mealling, M., "Dynamic Delegation Discovery System (DDDS)
Part One: The Comprehensive DDDS", RFC 3401, October 2002.

[RFC3833] Atkins, D., "Threat Analysis of the Domain Name System
(DNS)", RFC 3833, August 2004.

[RFC5088] Le Roux, JL., "OSPF Protocol Extensions for Path
Computation Element (PCE) Discovery", RFC 5088,
January 2008.

[RFC5089] Le Roux, JL., "IS-IS Protocol Extensions for Path
Computation Element (PCE) Discovery", RFC 5089,
January 2008.

[RFC5245] Rosenberg, J., "Interactive Connectivity Establishment
(ICE): A Protocol for Network Address Translator (NAT)
Traversal for Offer/Answer Protocols", RFC 5245,
April 2010.

[RFC5295] Touch, J., "The TCP Authentication Option", RFC 5295,
June 2010.

[RFC5382] Guha, S., "NAT Behavioral Requirements for TCP", RFC 5382,
October 2008.

[RFC5452] Hubert, A., "Measures for Making DNS More Resilient
against Forged Answers", RFC 5452, January 2009.

Authors' Addresses

Qin Wu
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China

Email: sunseawq@huawei.com

Dhruv Dhody
Huawei
Leela Palace
Bangalore, Karnataka 560008
INDIA

Email: dhruv.ietf@gmail.com dhruv.dhody@huawei.com

Daniel King
Old Dog Consulting
UK

Email: daniel@olddog.co.uk

Diego R. Lopez
Telefonica I+D

Email: diego@tid.es