draft-ietf-idr-rfc4893bis-03.txt   draft-ietf-idr-rfc4893bis-04.txt 
Network Working Group Q. Vohra Network Working Group Q. Vohra
Internet Draft Juniper Networks Internet Draft Juniper Networks
Obsoletes: 4893 (if approved) E. Chen Obsoletes: 4893 (if approved) E. Chen
Intended Status: Standards Track Cisco Systems Intended Status: Standards Track Cisco Systems
Expiration Date: April 5, 2011 October 4, 2010 Expiration Date: Jan 12, 2012 July 11, 2011
BGP Support for Four-octet AS Number Space BGP Support for Four-octet AS Number Space
draft-ietf-idr-rfc4893bis-03.txt draft-ietf-idr-rfc4893bis-04.txt
Status of this Memo Status of this Memo
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skipping to change at page 1, line 33 skipping to change at page 1, line 33
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Copyright Notice Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the Copyright (c) 2011 IETF Trust and the persons identified as the
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Abstract Abstract
Currently the Autonomous System (AS) number is encoded as a two-octet The Autonomous System (AS) number is encoded as a two-octet entity in
entity in BGP. This document describes extensions to BGP to carry the the base BGP specification. This document describes extensions to BGP
Autonomous System number as a four-octet entity. to carry the Autonomous System numbers as four-octet entities.
1. Introduction 1. Introduction
Currently the Autonomous System number is encoded as a two-octet In the base BGP specification [RFC4271] the Autonomous System number
entity in BGP [RFC4271]. To prepare for the anticipated exhaustion is encoded as a two-octet entity. To prepare for the anticipated
of the two-octet AS numbers, this document describes extensions to exhaustion of the two-octet AS numbers, this document describes
BGP to carry the Autonomous System number as a four-octet entity. extensions to BGP to carry the Autonomous System numbers as four-
octet entities.
More specifically, this document defines a new BGP capability, Four- More specifically, this document defines a BGP capability, "support
octet AS Number Capability, that can be used by a BGP speaker to for 4-octet AS number capability", to be used by a BGP speaker to
indicate its support for the four-octet AS numbers. Two new indicate its support for the four-octet AS numbers. Two attributes,
attributes, AS4_PATH and AS4_AGGREGATOR, are introduced that can be AS4_PATH and AS4_AGGREGATOR, are introduced that can be used to
used to propagate four-octet based AS path information across BGP propagate four-octet based AS path information across BGP speakers
speakers that do not support the four-octet AS numbers. This that do not support the four-octet AS numbers. This document also
document also specifies mechanisms for constructing the AS path specifies mechanisms for constructing the AS path information from
information from the AS_PATH attribute and the AS4_PATH attribute. the AS_PATH attribute and the AS4_PATH attribute.
The extensions specified in this document allow a gradual transition The extensions specified in this document allow a gradual transition
from 2-octet AS numbers to 4-octet AS numbers. from 2-octet AS numbers to 4-octet AS numbers.
2. Specification of Requirements 2. Specification of Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
3. Protocol Extensions 3. Protocol Extensions
For the purpose of this document we define a BGP speaker that does For the purpose of this document we define a BGP speaker that does
not support the new 4-octet AS number extensions as an OLD BGP not support the new 4-octet AS number extensions as an OLD BGP
speaker, and a BGP speaker that supports the new 4-octet AS number speaker, and a BGP speaker that supports the new 4-octet AS number
extensions as a NEW BGP speaker. extensions as a NEW BGP speaker.
BGP carries the Autonomous System number in the "My Autonomous BGP carries the Autonomous System numbers in the "My Autonomous
System" field of the OPEN message, in the AS_PATH attribute of the System" field of the OPEN message, in the AS_PATH attribute of the
UPDATE message, and in the AGGREGATOR attribute of the UPDATE UPDATE message, and in the AGGREGATOR attribute of the UPDATE
message. BGP also carries the Autonomous System number in the BGP message. BGP also carries the Autonomous System numbers in the BGP
Communities attribute. Communities attribute.
A NEW BGP speaker uses BGP Capability Advertisements [RFC5492] to A NEW BGP speaker uses BGP Capability Advertisements [RFC5492] to
advertise to its neighbors (either internal or external) that it advertise to its neighbors (either internal or external) that it
supports 4-octet AS number extensions, as specified in this document. supports 4-octet AS number extensions, as specified in this document.
The Capability that is used by a BGP speaker to convey to its BGP The Capability that is used by a BGP speaker to convey to its BGP
peer the 4-octet Autonomous System number capability, also carries peer the 4-octet Autonomous System number capability, also carries
the Autonomous System number (encoded as a 4-octet entity) of the the Autonomous System number (encoded as a 4-octet entity) of the
speaker in the Capability Value field of the Capability Optional speaker in the Capability Value field of the Capability Optional
Parameter. The Capability Length field of the Capability is set to Parameter. The Capability Length field of the Capability is set to
4. 4.
NEW BGP speakers carry AS path information expressed in terms of 4- The AS path information exchanged between NEW BGP speakers are
octet Autonomous Systems numbers by using the existing AS_PATH carried in the existing AS_PATH attribute, except that each AS number
attribute, except that each AS number in this attribute is encoded in the attribute is encoded as a 4-octet entity (instead of a 2-octet
not as a 2-octet, but as a 4-octet entity. The same applies to the entity). The same applies to the AGGREGATOR attribute - the same
AGGREGATOR attribute - NEW BGP speakers use the same attribute, attribute is used between NEW BGP speakers, except that the AS number
except that the AS carried in this attribute is encoded as a 4-octet carried in the attribute is encoded as a 4-octet entity.
entity.
To preserve AS path information with 4-octet AS numbers across OLD The AS_PATH attribute and the AGGREGATOR attribute carried between a
BGP speakers, this document defines a new AS path attribute, called NEW BGP speaker and an OLD BGP speaker will continue to contain 2-
AS4_PATH. This is an optional transitive attribute that contains the octet AS numbers.
AS path encoded with 4-octet AS numbers. The AS4_PATH attribute has
the same semantics as the AS_PATH attribute, except that it is To preserve the AS path information with 4-octet AS numbers across
optional transitive, and it carries 4-octet AS numbers. OLD BGP speakers, this document defines a new AS path attribute,
called AS4_PATH. This is an optional transitive attribute that
contains the AS path encoded with 4-octet AS numbers. The AS4_PATH
attribute has the same semantics as the AS_PATH attribute, except
that it is optional transitive, and it carries 4-octet AS numbers.
To prevent the possible propagation of confederation path segments To prevent the possible propagation of confederation path segments
outside of a confederation, the path segment types AS_CONFED_SEQUENCE outside of a confederation, the path segment types AS_CONFED_SEQUENCE
and AS_CONFED_SET [RFC5065] are declared invalid for the AS4_PATH and AS_CONFED_SET [RFC5065] are declared invalid for the AS4_PATH
attribute, and MUST NOT be carried in an UPDATE message. attribute, and MUST NOT be included in the AS4_PATH attribute of an
UPDATE message.
Similarly, this document defines a new aggregator attribute called Similarly, this document defines a new aggregator attribute called
AS4_AGGREGATOR, which is optional transitive. The AS4_AGGREGATOR AS4_AGGREGATOR, which is optional transitive. The AS4_AGGREGATOR
attribute has the same semantics as the AGGREGATOR attribute, except attribute has the same semantics as the AGGREGATOR attribute, except
that it carries a 4-octet AS number. that it carries a 4-octet AS number.
Currently assigned 2-octet Autonomous System numbers are converted Currently assigned 2-octet Autonomous System numbers are converted
into 4-octet Autonomous System numbers by setting the two high-order into 4-octet Autonomous System numbers by setting the two high-order
octets of the 4-octet field to zero. Such a 4-octet AS number is octets of the 4-octet field to zero. Such a 4-octet AS number is
said to be mappable to a 2-octet AS number. said to be mappable to a 2-octet AS number.
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this special AS number as AS_TRANS for ease of description in the this special AS number as AS_TRANS for ease of description in the
rest of this specification. This AS number is also placed in the "My rest of this specification. This AS number is also placed in the "My
Autonomous System" field of the OPEN message originated by a NEW BGP Autonomous System" field of the OPEN message originated by a NEW BGP
speaker, if the speaker does not have a (globally unique) 2-octet AS speaker, if the speaker does not have a (globally unique) 2-octet AS
number. number.
4. Operations 4. Operations
4.1. Interaction Between NEW BGP Speakers 4.1. Interaction Between NEW BGP Speakers
A BGP speaker that supports 4-octet Autonomous System numbers SHOULD A BGP speaker that supports 4-octet Autonomous System numbers SHALL
advertise this to its peers using the BGP Capability Advertisements. advertise this to its peers using the BGP Capability Advertisements.
The Autonomous System number of the BGP speaker MUST be carried in The Autonomous System number of the BGP speaker MUST be carried in
the capability value field of the advertised capability. the capability value field of the "support for 4-octet AS number
capability".
When a NEW BGP speaker processes an OPEN message from another NEW BGP When a NEW BGP speaker processes an OPEN message from another NEW BGP
speaker, it MUST use the Autonomous System number encoded in the speaker, it MUST use the Autonomous System number encoded in the
Capability Value field of the Capability in lieu of the "My Capability Value field of the Capability in lieu of the "My
Autonomous System" field of the OPEN message. Autonomous System" field of the OPEN message.
A BGP speaker that advertises such capability to a particular peer, A BGP speaker that advertises such capability to a particular peer,
and receives from that peer the advertisement of such capability MUST and receives from that peer the advertisement of such capability MUST
encode Autonomous System numbers as 4-octet entities in both the encode Autonomous System numbers as 4-octet entities in both the
AS_PATH and the AGGREGATOR attributes in the updates it sends to the AS_PATH and the AGGREGATOR attributes in the updates it sends to the
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the AS4_PATH attribute. the AS4_PATH attribute.
In the AS_PATH attribute encoded with 2-octet AS numbers, non- In the AS_PATH attribute encoded with 2-octet AS numbers, non-
mappable 4-octet AS numbers are represented by the well-known 2-octet mappable 4-octet AS numbers are represented by the well-known 2-octet
AS number, AS_TRANS. This will preserve the path length property of AS number, AS_TRANS. This will preserve the path length property of
the AS path information and also help in updating the AS path the AS path information and also help in updating the AS path
information received on a NEW BGP speaker from an OLD speaker, as information received on a NEW BGP speaker from an OLD speaker, as
explained in the next section. explained in the next section.
The NEW speaker constructs the AS4_PATH attribute from the AS path The NEW speaker constructs the AS4_PATH attribute from the AS path
information. In the case where the AS path information contains information. Whenever the AS path information contains the
either AS_CONFED_SEQUENCE or AS_CONFED_SET path segments, the NEW AS_CONFED_SEQUENCE or AS_CONFED_SET path segment, the NEW BGP speaker
speaker, when constructing the AS4_PATH attribute from the AS path MUST exclude such path segments from the AS4_PATH attribute being
information, MUST exclude such path segments. The AS4_PATH attribute constructed.
will be carried across a series of OLD BGP speakers without
modification and will help preserve the non-mappable 4-octet AS The AS4_PATH attribute, being optional transitive, will be carried
numbers in the AS path information. across a series of OLD BGP speakers without modification and will
help preserve the non-mappable 4-octet AS numbers in the AS path
information.
Similarly, if the NEW speaker has to send the AGGREGATOR attribute, Similarly, if the NEW speaker has to send the AGGREGATOR attribute,
and if the aggregating Autonomous System's AS number is a non- and if the aggregating Autonomous System's AS number is a non-
mappable 4-octet AS number, then the speaker MUST use the mappable 4-octet AS number, then the speaker MUST use the
AS4_AGGREGATOR attribute, and set the AS number field in the existing AS4_AGGREGATOR attribute, and set the AS number field in the existing
AGGREGATOR attribute to the reserved AS number, AS_TRANS. Note that AGGREGATOR attribute to the reserved AS number, AS_TRANS. Note that
if the AS number is 2-octets only, then the AS4_AGGREGATOR attribute if the AS number is 2-octets only, then the AS4_AGGREGATOR attribute
MUST NOT be sent. MUST NOT be sent.
4.2.3. Processing Received Updates 4.2.3. Processing Received Updates
When a NEW BGP speaker receives an update from an OLD one, it should When a NEW BGP speaker receives an update from an OLD one, it MUST be
be prepared to receive the AS4_PATH attribute along with the existing prepared to receive the AS4_PATH attribute along with the existing
AS_PATH attribute. If the AS4_PATH attribute is also received, both AS_PATH attribute. If the AS4_PATH attribute is also received, both
the attributes will be used to construct the exact AS path the attributes will be used to construct the exact AS path
information, and therefore the information carried by both the information, and therefore the information carried by both the
attributes will be considered for AS path loop detection. attributes will be considered for AS path loop detection.
Note that a route may have traversed a series of autonomous systems Note that a route may have traversed a series of autonomous systems
with 2-octet AS numbers and OLD BGP speakers only. In that case, if with 2-octet AS numbers and OLD BGP speakers only. In that case, if
the route carries the AS4_PATH attribute, this attribute must have the route carries the AS4_PATH attribute, this attribute must have
remained unmodified since the route left the last NEW BGP speaker. remained unmodified since the route left the last NEW BGP speaker.
The trailing AS path information (representing autonomous systems The trailing AS path information (representing autonomous systems
with 2-octet AS numbers and OLD BGP speakers only) is contained only with 2-octet AS numbers and OLD BGP speakers only) is contained only
in the current AS_PATH attribute (encoded in the leading part of the in the current AS_PATH attribute (encoded in the leading part of the
AS_PATH attribute). AS_PATH attribute).
Under certain conditions, it may not be possible to reconstruct the Under certain conditions, it may not be possible to reconstruct the
entire AS path information from the AS_PATH and the AS4_PATH entire AS path information from the AS_PATH and the AS4_PATH
attributes of a route. This occurs when two or more routes that attributes of a route. This occurs, for example, when two or more
carry the AS4_PATH attribute are aggregated by an OLD BGP speaker, routes that carry the AS4_PATH attribute are aggregated by an OLD BGP
and the AS4_PATH attribute of at least one of these routes carries at speaker, and the AS4_PATH attribute of at least one of these routes
least one 4-octet AS number (as oppose to a 2-octet AS number that is carries at least one 4-octet AS number (as oppose to a 2-octet AS
encoded in 4 octets). Depending on the implementation, either the number that is encoded in 4 octets). Depending on the
AS4_PATH attribute would be lost during route aggregation, or both implementation, either the AS4_PATH attribute would be lost during
the AS_PATH attribute and the AS4_PATH attribute would contain valid, route aggregation, or both the AS_PATH attribute and the AS4_PATH
partial information that cannot be combined seamlessly, resulting in attribute would contain valid, partial information that cannot be
incomplete AS path information in these cases. combined seamlessly, resulting in incomplete AS path information in
these cases.
A NEW BGP speaker should also be prepared to receive the A NEW BGP speaker MUST also be prepared to receive the AS4_AGGREGATOR
AS4_AGGREGATOR attribute along with the AGGREGATOR attribute from an attribute along with the AGGREGATOR attribute from an OLD BGP
OLD BGP speaker. When both the attributes are received, if the AS speaker. When both the attributes are received, if the AS number in
number in the AGGREGATOR attribute is not AS_TRANS, then: the AGGREGATOR attribute is not AS_TRANS, then:
- the AS4_AGGREGATOR attribute and the AS4_PATH attribute SHALL - the AS4_AGGREGATOR attribute and the AS4_PATH attribute SHALL
be ignored, be ignored,
- the AGGREGATOR attribute SHALL be taken as the information - the AGGREGATOR attribute SHALL be taken as the information
about the aggregating node, and about the aggregating node, and
- the AS_PATH attribute SHALL be taken as the AS path - the AS_PATH attribute SHALL be taken as the AS path
information. information.
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As specified in [RFC1997], when the high-order two-octets of the As specified in [RFC1997], when the high-order two-octets of the
community attribute is neither 0x0000 nor 0xffff, these two octets community attribute is neither 0x0000 nor 0xffff, these two octets
encode the Autonomous System number. Quite clearly this would not encode the Autonomous System number. Quite clearly this would not
work for a NEW BGP speaker with a non-mappable 4-octet AS number. work for a NEW BGP speaker with a non-mappable 4-octet AS number.
Such BGP speakers should use the Four-octet AS Specific Extended Such BGP speakers should use the Four-octet AS Specific Extended
Communities [RFC5668] instead. Communities [RFC5668] instead.
6. Error Handling 6. Error Handling
The general guidelines presented in [OPT-TRANS] apply to the error
handling of the AS4_PATH and AS4_AGGREGATOR attributes introduced in
this document. It is noted, however, that the nature (i.e., NEW
speaker or OLD speaker) of a direct neighbor based on the
announcement of the 4-octet AS Capability allows a local speaker to
determine unequivocally whether the direct neighbor recognizes these
new attributes. Thus there is no need to examine the the attribute
flags (somewhat weaker indicator in this case) for that
determination.
Given that the two-octet AS numbers dominate during the transition, Given that the two-octet AS numbers dominate during the transition,
and are carried in the AS_PATH attribute by an OLD BGP speaker, in and are carried in the AS_PATH attribute by an OLD BGP speaker, in
this document the "attribute discard" approach is chosen to handle a this document the "attribute discard" approach is chosen to handle a
malformed AS4_PATH attribute. malformed AS4_PATH attribute.
Similarly, as the AS4_AGGREGATOR is just informational, the Similarly, as the AS4_AGGREGATOR is just informational, the
"attribute discard" approach is chosen to handle a malformed "attribute discard" approach is chosen to handle a malformed
AS4_AGGREGATOR attribute. AS4_AGGREGATOR attribute.
The AS4_PATH attribute and AS4_AGGREGATOR attribute MUST NOT be The AS4_PATH attribute and AS4_AGGREGATOR attribute MUST NOT be
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The scheme described in this document allows a gradual transition The scheme described in this document allows a gradual transition
from 2-octet AS numbers to 4-octet AS numbers. One can upgrade one from 2-octet AS numbers to 4-octet AS numbers. One can upgrade one
Autonomous System or one BGP speaker at a time. Autonomous System or one BGP speaker at a time.
To simplify transition, this document assumes that an Autonomous To simplify transition, this document assumes that an Autonomous
System could start using a 4-octet AS number only after all the BGP System could start using a 4-octet AS number only after all the BGP
speakers within that Autonomous System have been upgraded to support speakers within that Autonomous System have been upgraded to support
4-octet AS numbers. 4-octet AS numbers.
An OLD BGP speaker MUST NOT use AS_TRANS as its Autonomous System
number.
A non-mappable 4-octet AS number cannot be used as a "Member AS A non-mappable 4-octet AS number cannot be used as a "Member AS
Number" of a BGP Confederation until all the BGP speakers within the Number" of a BGP Confederation until all the BGP speakers within the
Confederation have transitioned to support 4-octet AS numbers. Confederation have transitioned to support 4-octet AS numbers.
In an environment where an Autonomous System that has OLD BGP In an environment where an Autonomous System that has OLD BGP
speakers peers with two or more Autonomous Systems that have NEW BGP speakers peers with two or more Autonomous Systems that have NEW BGP
speakers and use AS_TRANS (rather than having a globally unique AS speakers and use AS_TRANS (rather than having a globally unique AS
number), use of Multi-Exit Discriminators by the Autonomous System number), use of Multi-Exit Discriminators by the Autonomous System
with the OLD speakers may result in a situation where Multi-Exit with the OLD speakers may result in a situation where Multi-Exit
Discriminator will influence route selection among the routes that Discriminator will influence route selection among the routes that
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This document expands the pool for AS numbers from 0 - 65535 to 0 - This document expands the pool for AS numbers from 0 - 65535 to 0 -
4294967295. The AS numbers are managed by the IANA "Autonomous 4294967295. The AS numbers are managed by the IANA "Autonomous
System Numbers" registry. Other than expanding the AS number pool, System Numbers" registry. Other than expanding the AS number pool,
this document does not propose any modifications to the existing this document does not propose any modifications to the existing
policies and procedures pertaining to the AS number allocation. policies and procedures pertaining to the AS number allocation.
This document uses a BGP Capability code to indicate that a BGP This document uses a BGP Capability code to indicate that a BGP
speaker supports the 4-octet AS numbers. The Capability Code 65 has speaker supports the 4-octet AS numbers. The Capability Code 65 has
been assigned by IANA per [RFC5492]. been assigned by IANA per [RFC5492].
In addition, this document introduces two new BGP optional transitive In addition, this document introduces two BGP optional transitive
attributes, and their type codes have been assigned by the IANA. The attributes, and their type codes have been assigned by the IANA. The
first one is the AS4_PATH attribute, value 17, which preserves the AS first one is the AS4_PATH attribute, value 17, which preserves the AS
path information with 4-octet AS numbers across old BGP speakers. path information with 4-octet AS numbers across old BGP speakers.
The second one is the AS4_AGGREGATOR attribute, value 18, which is The second one is the AS4_AGGREGATOR attribute, value 18, which is
similar in use to the current AGGREGATOR attribute, but it carries a similar in use to the current AGGREGATOR attribute, but it carries a
4-octet AS number. 4-octet AS number.
Finally, this document introduces a reserved 2-octet AS number -- Finally, this document introduces a reserved 2-octet AS number --
AS_TRANS. The AS number 23456 has been assigned by the IANA for AS_TRANS. The AS number 23456 has been assigned by the IANA for
AS_TRANS. AS_TRANS.
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10. Acknowledgments 10. Acknowledgments
The authors would like to thank Yakov Rekhter, Chaitanya Kodeboyina, The authors would like to thank Yakov Rekhter, Chaitanya Kodeboyina,
and Jeffrey Haas for the numerous discussions that went into the and Jeffrey Haas for the numerous discussions that went into the
making of this document. making of this document.
The authors would also like to thank members of the IDR Working Group The authors would also like to thank members of the IDR Working Group
for their review and comments. for their review and comments.
11. References 11. Normative References
11.1. Normative References
[RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
Border Gateway Protocol 4 (BGP-4)", RFC 4271, January Border Gateway Protocol 4 (BGP-4)", RFC 4271, January
2006. 2006.
[RFC1997] Chandra, R., Traina, P., and T. Li, "BGP Communities [RFC1997] Chandra, R., Traina, P., and T. Li, "BGP Communities
Attribute", RFC 1997, August 1996. Attribute", RFC 1997, August 1996.
[RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement [RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement
with BGP-4", RFC 5492, February 2009. with BGP-4", RFC 5492, February 2009.
[RFC5065] Traina, P., McPherson, D., and J. Scudder, "Autonomous [RFC5065] Traina, P., McPherson, D., and J. Scudder, "Autonomous
System Confederations for BGP", RFC 5065, August 2007. System Confederations for BGP", RFC 5065, August 2007.
[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, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
11.2. Informative References
[RFC5668] Rekhter, Y., Ramachandra, S., and D. Tappan, "4-Octet AS [RFC5668] Rekhter, Y., Ramachandra, S., and D. Tappan, "4-Octet AS
Specific BGP Extended Community", RFC 5668, October 2009. Specific BGP Extended Community", RFC 5668, October 2009.
[OPT-TRANS] Scudder, J. and E. Chen, "Error Handling for Optional
Transitive BGP Attributes", Work in Progress, March 2010.
Appendix A. Comparison with RFC 4893 Appendix A. Comparison with RFC 4893
This document includes several minor editorial changes, and specifies This document includes several editorial changes, and specifies the
the error handling for the new attributes. error handling for the new attributes.
12. Authors' Addresses 12. Authors' Addresses
Quaizar Vohra Quaizar Vohra
Juniper Networks Juniper Networks
1194 N. Mathilda Ave. 1194 N. Mathilda Ave.
Sunnyvale, CA 94089 Sunnyvale, CA 94089
USA
EMail: quaizar.vohra@gmail.com EMail: quaizar.vohra@gmail.com
Enke Chen Enke Chen
Cisco Systems, Inc. Cisco Systems, Inc.
170 W. Tasman Dr. 170 W. Tasman Dr.
San Jose, CA 95134 San Jose, CA 95134
USA
EMail: enkechen@cisco.com EMail: enkechen@cisco.com
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