Internet DRAFT - draft-amjads-ipsecme-ikev2-data-channel
draft-amjads-ipsecme-ikev2-data-channel
Network Working Group Amjad. Inamdar
Internet-Draft R. Singh
Intended status: Standards Track Cisco
Expires: September 13, 2014 March 12, 2014
IKEv2 based lightweight secure data communication
draft-amjads-ipsecme-ikev2-data-channel-01 (D-IKE)
Abstract
The Internet Key Exchange (IKEv2) protocol provides authentication,
confidentiality, integrity, data-origin authentication and anti-
replay. Currently, IKEv2 is mainly used as a control channel to
negotiate IPsec SA(s). IPsec is not well suited to provide transport
layer security for applications as it resides at the network layer
and most of the IPsec implementations require integration into
operating systems making it difficult to deploy. IPsec uses
different sessions for control and data traffic which is not NAT and
load balancer friendly. TLS/DTLS, the other popular security
mechanism to provide the above security services does not mandate
mutual peer authentication and Diffie Hellman exchange.
This document describes an IKEv2 based lightweight secure data
communication protocol and a way to provide transport layer security
for UDP client/server applications. The protocol provides integrity
protected encryption and integrity-only protection based on
application needs. As most of the IoT applications are UDP based,
IKEv2 can be used for key management as well secure data
communication in IoT due to its simplicity, scalability,
lightweightedness and ease of deployment.
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
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 13, 2014.
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Copyright Notice
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document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. D-IKE comparision with IPsec . . . . . . . . . . . . . . . . 3
4. D-IKE comparision with DTLS . . . . . . . . . . . . . . . . . 4
5. D-IKE Description . . . . . . . . . . . . . . . . . . . . . . 4
6. Securing UDP applications with D-IKE . . . . . . . . . . . . 4
7. Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . 7
8. Protocol Outline . . . . . . . . . . . . . . . . . . . . . . 7
9. D-IKE capabilities . . . . . . . . . . . . . . . . . . . . . 7
9.1. Encryption and Integrity protection . . . . . . . . . . . 7
9.2. Integrity only protection . . . . . . . . . . . . . . . . 8
10. D-IKE negotiation . . . . . . . . . . . . . . . . . . . . . . 8
11. D-IKE packet and payload formats . . . . . . . . . . . . . . 9
11.1. D-IKE_SUPPORTED Notify payload . . . . . . . . . . . . . 9
11.2. D-IKE Control and Data packets . . . . . . . . . . . . . 10
11.3. D-IKE payload . . . . . . . . . . . . . . . . . . . . . 11
12. Security Considerations . . . . . . . . . . . . . . . . . . . 11
13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
14. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12
15. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 12
15.1. Draft -01 . . . . . . . . . . . . . . . . . . . . . . . 12
16. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
16.1. Normative References . . . . . . . . . . . . . . . . . . 13
16.2. Informative References . . . . . . . . . . . . . . . . . 13
Appendix A. Design decisions . . . . . . . . . . . . . . . . . . 13
A.1. Use of the existing IKEv2 control channel . . . . . . . . 13
A.2. IKEv2 header modification . . . . . . . . . . . . . . . . 14
A.3. Use of separate UDP port for data channel . . . . . . . . 14
Appendix B. Possible extensions . . . . . . . . . . . . . . . . 14
B.1. Securing TCP client/server applications using D-IKE . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Introduction
The Internet Key Exchange Protocol version 2 (IKEv2), specified in
RFC5996 [1], is a UDP based protocol that provides a secure
communication channel similar to ESP defined in RFC4303 [2]. IKEv2
defines mechanisms for mutual authentication of peers, key
management, SA management and exchange of configuration information.
IKEv2 is mainly used as a secure control channel to negotiate child
IPsec SAs. As IKEv2 provides encryption, integrity protection, data
origin authenication and replay protection similar to ESP, IKEv2 can
be leveraged for secure data communication. This document defines an
IKEv2 based secure data communication mechanism (henceforth referred
to as D-IKE) and describes a way to secure UDP applications with
D-IKE. While the IKE control channel is always encryption and
integrity protected, the IKE data channel can provide encryption and
integrity protection as well as integrity-only protection depending
on the needs of the application.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [7].
3. D-IKE comparision with IPsec
o D-IKE being UDP based is easier to deploy as it resides in the
operating system application space and does not require
integration with the operating system kernel unlike most of the
IPsec implementations
o D-IKE is lighter with fewer keys and protocol exchanges as it uses
the same channel for control messages and data
o D-IKE is simpler as it does not involve programming the Security
Policy Database (SPD)
o D-IKE being at transport layer is better suited to provide
granular and end-to-end security to applications than IPsec which
provides network layer security suitable for site to site
o D-IKE control and data channels run over a single UDP port and
hence D-IKE is load balancer friendly
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4. D-IKE comparision with DTLS
o D-IKE provides better enforcement of security through mandatory
mutual peer authentication and Diffie Hellman key exchange
o D-IKE supports comprehensive authentication methods and has built-
in support for mobility, DOS attack mitigation and load balancing
5. D-IKE Description
Each UDP application using D-IKE for security will use different UDP
port numbers. So with D-IKE, IKEv2 packets are no longer identified
by UDP ports 500 and 4500. D-IKE will use a different UDP port
number for each UDP application to carry the D-IKE control messages
for IKEv2 negotiation as well as application data. The first octet
in the UDP payload will identify D-IKE control and data packets.
D-IKE control packets will carry the IKEv2 header and payloads as
defined in RFC5996 [1] and will be used to negotiate a childless
IKEv2 session between UDP client and server. D-IKE data packets will
carry encrypted and authenticated UDP application data.
The following diagram depicts the format of UDP encapsulated D-IKE
control and Data packets.
+------------+------+----------+---------------------------+
| UDP Header | Type | RESERVED | D-IKE Control/Data Packet |
+------------+------+----------+---------------------------+
|<---------------- UDP Payload -------------->|
Encapsulation of D-IKE packets
D-IKE can provide integrity-only protection in addition to integrity
protected encryption. D-IKE does not negotiate child IPsec SAs in
the IKEv2 initial exchange and subsequently as depicted in D-IKE
Negotiation section, similar to Childless IKEv2 defined in RFC6023
[3].
Please refer the appendix section of this document for details on the
alternative mechanisms that were considered for data communication
over IKEv2 and their drawbacks.
6. Securing UDP applications with D-IKE
This document introduces the concept of D-IKE sockets to secure
communication between UDP client/server applications. D-IKE socket
is an IKEv2 session between a UDP client and server uniquely
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identified by the 4 tuple of client and server IP addresses and UDP
ports.
+--------------+ +--------------+
| UDP Client | | UDP Service |
+--------------+ +--------------+
| D-IKE socket | | D-IKE socket |
+--------------+ +--------------+
| UDP | | UDP |
+--------------+ +--------------+
| IP |<------------>| IP |
+--------------+ +--------------+
D-IKE Sockets
o A UDP service will register with D-IKE socket specifying the UDP
port it wants to listen to. D-IKE will listen on the UDP port
number on behalf of the application
o A UDP client will open a D-IKE socket specifying the server IP
address and the UDP port number. D-IKE will open a UDP socket to
the server on behalf of the client
o D-IKE will initiate an IKEv2 session without any child SA from UDP
client to the server
o After successful negotiation of IKEv2 session, the client and
server can securely exchange data over D-IKE socket
UDP Client UDP Server
---------- ----------
| |
|<-------- IKE negotiation --------->|
| |
|<----- Secure Data Transfer ------->|
| |
Secure UDP communication over D-IKE
For a node running multiple UDP applications(Clients and/or
Services), each UDP application will have a unique D-IKE socket
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+----------------+----------------+----------------+
| UDP App 1 | UDP App 2 | UDP App N |
+----------------+----------------+----------------+
| D-IKE socket 1 | D-IKE socket 2 | D-IKE socket N |
+----------------+----------------+----------------+
| UDP |
+--------------------------------------------------+
| IP |
+--------------------------------------------------+
D-IKE socket per UDP Application
A well known UDP service can simultaneously open a UDP socket as well
as D-IKE socket.
+--------------+ +---------------------------+ +------------+
| UDP Client | | UDP Service | | UDP Client |
+--------------+ +---------------------------+ +------------+
| D-IKE socket | | D-IKE socket | UDP Socket |<-->| UDP Socket |
+--------------+ +--------------+------------+ +------------+
| UDP |<-->| UDP | |<-- Unsecured -->|
+--------------+ +--------------+ Communication
|<----- Secure ----->|
Communication
Securing UDP Applications using D-IKE
The following diagram shows the format of D-IKE packet.
|<------------- D-IKE packet -------------->|
+----+------+--------+-------------+---------+----------+
| IP | UDP | D-IKE | UDP App | D-IKE | D-IKE |
| | | Header | Data | Trailer | Checksum |
+----+------+--------+-------------+-- ------+----------+
| |<----- Encrypted ----->|
|<----- Integrity Protected ---->|
D-IKE packet format
D-IKE packet consists of D-IKE header, UDP application data, an
optional D-IKE trailer and D-IKE integrity checksum value.
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7. Benefits
o Lightweight, scalable and simpler with fewer keys and protocol
exchanges
o Support for integrity-only protection, in addition to integrity
protected encryption
o Works seamlessly with load balancers and PAT devices as D-IKE uses
the same UDP port as the IKEv2 control channel
8. Protocol Outline
This document proposes following extensions to IKEv2 protocol for
data communication:
o IKEv2 Notify type 'D-IKE_SUPPORTED' to negotiate the use of IKEv2
for data communication
o D-IKE packet formats
9. D-IKE capabilities
D-IKE will support the following data protection modes:
o Encryption and Integrity protection
o Integrity only protection
9.1. Encryption and Integrity protection
This protection mode provides encryption and integrity protection of
D-IKE packets similar to the IKEv2 Encrypted payload as defined in
RFC5996 [1]
The UDP app data and D-IKE trailer are encrypted and the D-IKE
header, UDP app data and D-IKE trailer are integrity protected.
+----+------+--------+-------------+---------+----------+
| IP | UDP | D-IKE | UDP App | D-IKE | D-IKE |
| | | Header | Data | Trailer | Checksum |
+----+------+--------+-------------+-- ------+----------+
| |<----- Encrypted ----->|
|<----- Integrity Protected ---->|
Encryption and Integrity protection
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9.2. Integrity only protection
This protection mode provides integrity protection of IKEv2 data
packets and no encryption similar to ESP null encryption as described
in RFC4303 [2]. This is suitable for applications that just need
data integrity and not confidentiality such as routing protocol
exchanges. It may be noted that integrity only protection applies
only to D-IKE packets and that D-IKE control packets will always use
integrity protected encryption.
The UDP app data and D-IKE trailer are encrypted and the D-IKE
header, UDP app data and D-IKE trailer are integrity protected.
+----+------+--------+-------------+----------+
| IP | UDP | D-IKE | UDP App | D-IKE |
| | | Header | Data | Checksum |
+----+------+--------+-------------+----------+
|<---- Integrity ----->|
Protected
Integrity only protection
10. D-IKE negotiation
IKEv2 nodes can negotiate to use D-IKE and its capabilities by
exchanging D-IKE_SUPPORTED Notify type in IKE_SA_INIT exchange.
o IKEv2 initiator can communicate its intent to use D-IKE by
including a notify payload of type D-IKE_SUPPORTED along with the
proposed capabilities in IKE_SA_INIT request
o IKEv2 responder can indicate its willingness to use D-IKE with the
proposed capabilities by including a notify payload of type
D-IKE_SUPPORTED along with the same capabilities in IKE_SA_INIT
response
o If the capabilities proposed by IKEv2 Initiator are not acceptable
to IKEv2 responder, it MUST NOT include D-IKE_SUPPORTED Notify
type in IKE_SA_INIT response
o The absence of Notify payload of type D-IKE_SUPPORTED in
IKE_SA_INIT response indicates the incapability or unwillingness
of the IKEv2 responder to use D-IKE
o If IKEv2 responder does not include the same capabilities as
proposed by IKEv2 initiator, IKEv2 initiator MUST treat this as
unsuccessful negotiation of D-IKE
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o On unsuccessful negotiation of D-IKE, IKEv2 initiator and
responder MUST NOT use D-IKE for data transfer. However rest of
the IKEv2 negotiation can proceed as normal
o On successful negotiation of D-IKE, IKEv2 Initiator and Responder
MUST exclude any payloads related to Child SA negotiation in
IKE_AUTH exchange and can use D-IKE for data transfer
Initiator Responder
------------------------------------------------------
HDR, SAi1, KEi, Ni
[N(D-IKE_SUPPORTED)] -->
<-- HDR, SAr1, KEr, Nr, [CERTREQ]
N(D-IKE_SUPPORTED)
HDR, SK {IDi, [CERT,]
[CERTREQ,] [IDr,]
AUTH, [CP(CFG_REQUEST)] -->
<-- HDR, SK {IDr, [CERT,] AUTH,
[CP(CFG_REPLY)]
IKEv2 data channel negotiation
11. D-IKE packet and payload formats
11.1. D-IKE_SUPPORTED Notify payload
1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! Next Payload !C! RESERVED ! Payload Length !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! Protocol ID ! SPI Size ! Notify Message Type !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! Flags ! RESERVED !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
D-IKE_SUPPORTED Notify payload
o Protocol ID (1 octet): MUST be 1, as this message is related to an
IKEv2 SA
o SPI Size (1 octet): MUST be zero, in conformance with section 3.10
of [RFC5996]
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o Notify Message Type (2 octets): MUST be xxxxx, the value assigned
for D-IKE_SUPPORTED by IANA
o Flags (8 bits): Specify the IKEv2 Data channel properties
* bit 0:
0 - Encryption and Integrity protection
1 - Integrity-only protection
* bit 1-7:
Reserved, sender MUST set these bits to zero and receiver
MUST ignore it
11.2. D-IKE Control and Data packets
The first octet in the UDP payload will identify D-IKE control and
data packets. D-IKE control packets will carry the IKEv2 header and
payloads as defined in RFC 5996 and will be used to negotiate a
childless IKEv2 session between UDP client and server. D-IKE data
packets will carry encrypted and authenticated UDP application data.
1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ IKEv2 Header and payloads ~
| or |
| D-IKE data payload |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
D-IKE Control and Data packets
o Type (1 octet, unsigned integer): Identifies D-IKE control and
data packet
* 0 - D-IKE control packet
* 1 - D-IKE data packet
* 2 - 7 - RESERVED
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11.3. D-IKE payload
1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length | RESERVED |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| SPI |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Initialization Vector |
| (length is block size for encryption algorithm) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Encrypted/Cleartext Data ~
+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Padding (0-255 octets) |
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
| | Pad Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
~ Integrity Checksum Data ~
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
D-IKE payload
o Length (2 octets, unsigned integer): Length in octets of the
entire IKEv2 Data packet
o Reserved (2 octets): Sender MUST set these bits to zero and
receiver MUST ignore these bits
o SPI (8 octets): A value used by receiver to lookup the session
associated with the packet in order to verify integrity and
decrypt the data packet. This value is usually the data packet
receiver's IKE SPI
o Sequence Number (4 octets): This field identifies the D-IKE packet
sequence numbers, used for anti-replay checks
12. Security Considerations
This protocol variation inherits all the security properties of
regular IKEv2 as described in [RFC5996]. The new notification
carried in the initial exchange advertises the capability, and cannot
be forged or added by an adversary without being detected, because
the response to the initial exchange is authenticated with the AUTH
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payload of the IKE_AUTH exchange. IKEv2 data payload inherits all
security properties of ESP protocol defined in [RFC4303].
13. IANA Considerations
This document introduces one new IKEv2 Notification Message types as
described in Section 11.1. The new Notify Message Types must be
assigned values between 16429 and 40959.
o D-IKE_SUPPORTED
For UDP applications that need a well known port number to secure the
application using D-IKE (for example, CoAP over D-IKE), the port
number MUST be reserved from IANA.
14. Acknowledgements
We would like to thank following people (in alphabetical order) for
their review comments and valuable suggestions for idea and initial
version of the document: Amit Phadnis, Arif Shouqi, Balaji B L, Brian
Weis, Cheryl Madson, Frederic Detienne, J P Vasseur, Kalyani
Garigipati, Mike Sullenberger, Naresh Sunkara, Nick Doyle, Paul
Hoffman, Rajiv Shankar Daulath, Ramesh Nethi, Sandeep Rao, Scott
Fluhrer, and Thamil Kandasamy.
15. Change Log
This section lists all the changes in this document.
NOTE TO RFC EDITOR: Please remove this section in before final RFC
publication.
15.1. Draft -01
Reworked the draft with more focus on UDP application security.
Updated the problem statement. Added comparision with IPsec and TLS/
DTLS. Updated D-IKE Notify and Data payloads. Added possible
extensions.
16. References
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16.1. Normative References
[1] Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen,
"Internet Key Exchange Protocol Version 2: IKEv2", RFC
5996, September 2010.
[2] Kent, S., "IP Encapsulating Security Payload (ESP)", RFC
4303, December 2005.
[3] Nir, Y., Tschofenig, H., Deng, H., and R. Singh, "A
Childless Initiation of IKEv2 SA", RFC 6023, October 2010.
[4] Smyslov, V., "IKEv2 Fragmentation", draft-ietf-ipsecme-
ikev2-fragmentation-02 (work in progress), September 2013.
[5] Rowles, S., Yeung, A., Tran, P., and Y. Nir, "Group Key
Management using IKEv2", draft-yeung-g-ikev2-06 (work in
progress), April 2013.
[6] Kivinen, T., "Minimal IKEv2", draft-ietf-lwig-
ikev2-minimal-00.txt (work in progress), April 2013.
[7] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
16.2. Informative References
[8] Devarapalli, V. and K. Weniger, "Redirect Mechanism for
IKEv2", RFC 5685, November 2009.
Appendix A. Design decisions
This section describes the alternative mechanisms for data
communication over IKEv2 that were considered and their drawbacks.
A.1. Use of the existing IKEv2 control channel
The existing IKEv2 control channel can be used for data transfer
using a new IKEv2 exchange type DATA exchange similar to
INFORMATIONAL exchange, and a new payload type to encapsulate
cleartext data that will be protected by Encrypted payload.
A drawback with this approach is that the data packets will incur the
overhead of IKEv2 header (28 octets) and a minimum of two generic
payload headers (4 octets each) with a total protocol overhead of 36
octets per data packet. Also, it is difficult to support
unacknowledged data transfer and integrity-only protection for data
packets.
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A.2. IKEv2 header modification
IKEv2 header can be modified to allow differentiation between control
and data packets using the first four bytes of the header and the
rest of the header can be different for control and data packets. A
possible way to accomplish this is to move the Exchange type field to
the beginning of IKEv2 header.
The obvious drawback with this approach is that it is not backward
compatible with existing IKEv2 protocol. Also, it makes it difficult
to support unacknowledged data transfer and integrity-only protection
for data packets.
A.3. Use of separate UDP port for data channel
A separate UDP port e.g 501 can be used for IKEv2 data channel that
allows to leverage the IKEv2 protocol's security and reliability
mechanisms and security parameters for data communication while
avoiding the overhead of IKEv2 header and generic payload headers for
data packets. Use of a fixed UDP port for data channel instead of
dynamically negotiated UDP ports has the advantage of not requiring
the firewalls to snoop the IKEv2 control channel to be able to
determine and allow the traffic on data channel UDP port.
A drawback with this approach is that the use of different ports for
IKEv2 control and data channels makes it difficult for load balancers
to associate an IKEv2 control channel with its data channel when
there are multiple IKEv2 initiators behind a PAT device. Also when
IKEv2 initiator is behind a PAT device, the data packets from
responder will be dropped by the PAT device as port 501 will not be
open unless there is data traffic from initiator.
Appendix B. Possible extensions
This section describes the possible extensions to D-IKE protocol.
B.1. Securing TCP client/server applications using D-IKE
D-IKE can be used to secure TCP applications using one of the
following methods.
o While IKE control channel can run over UDP, the IKE data channel
can negotiate and run over a TCP session carring D-IKE protected
application data. A drawback with this approach is that using
differnet sessions for control and data may not be friendly with
load balancers
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o If IKEv2 were to run over TCP, IKEv2 over TCP can be used to
secure TCP applications
o D-IKE tunnel mode can be defined that can encapsulate TCP or any
other protocol over D-IKE tunnel
Authors' Addresses
Amjad S. Inamdar
Cisco Systems India Pvt. Ltd.
SEZ Unit, Cessna Business Park
Sarjapur Marathahalli Outer Ring Road
Bangalore, Karnataka 560087
India
Phone: +91 80 4426 4834
Email: amjads@cisco.com
Rajeshwar Singh Janwar
Cisco Systems India Pvt. Ltd.
SEZ Unit, Cessna Business Park
Sarjapur Marathahalli Outer Ring Road
Bangalore, Karnataka 560087
India
Phone: +91 80 4426 2731
Email: rsj@cisco.com
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