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Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 1
Mehmud Ameen, Consulting Systems Engineer (CSE)Cisco EXPO April 2007
SP Voice
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 2
SP Voice Technology
� From Traditional PSTN to SP Packet Telephony
� Cisco Open Packet Telephony (OPT) Model
� VoIP Signaling Protocols
� Overview of Applications Enabled by OPT
� Business Voice Services
� Next Generation IMS Architecture
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 3
PSTN Basic Architecture
SS7 Signaling Link
Bearer Trunk
Access Line
SSP = Service Switching Point
SCP = Service Control Point
STP = Signal Transfer Point
PBX = Private Branch eXchange
Trunk Network
SSP
SSP
SSP
SignalingNetwork
Tie Line(Analog)
ISDN PRI (T1/E1)
Analog or ISDN BRI2/4-Wires
T1/E1/T3/E3/SONET/SDH
T1/E1 DS0, V.35
PBX
STPSCP SCP
STP
STP
PBX
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 4
Call Setup with SS7 ISUP
IAM
Initial Address Message
ACM
Address Complete Message
ANM
Answer Message
CIC
Circuit Identification Code
CIC X CIC Y
Line SeizedDTMF
IAMPC/CIC X
IAMPC/CIC X
IAMPC/CIC X
IAMPC/CIC Y
IAMPC/CIC Y
Ringing
IAM
IAM
ACMACM
ANMANM
Off-HookDTMF
Ringing
Off Hook
Number AnalysisTrunk (CIC) Selection
Ringback
STPSTP
STP
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 5
Traditional PSTN Model Summary
Call Control
Services
Platform Embedded
Call
Logic
Switching
Logic
Service
Logic
Service Layer
IN Voice Services
Call-Control LayerSignaling and Call Control
Service Access Function
Connection Layer
Circuit Selection
Circuit Switching
Accessing Serv
ices SS7 (INAP/TCAP)
Voice Switching
64 kbps
STP
DB DB
STP
X XX X
BillingBilling
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 6
SP Packet Telephony Architecture
Cable
ATM/FREthernet
ISDN DSL
QoS-ManagedPacket Core
Flexible Aggregation
Standard Interfaces
New IP-BasedServices
Traditional PSTN Services
Call Signalingand Routing
LL
Rich SignalingCapability
SCP
SS7
Carrier
Interconnects
Efficient BW Utilization
Internet
STP
TDM
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 7
Cisco Open Packet Telephony Model
� Responds to requests from the call control plane by instructing it how to treat calls
� Provides connectivity to AIN applications and engraves for development of new IP-based service products
� Responsible for processing call requests
� Directs the connection control plane to establish bearers
� End-to-end call context is maintained
� May initiate a service request to the services plane
� Manages switching logic associated with the bearer channels
� Performs codec transcoding
� Negotiations for connections, bearer switching, SIP/H.323
ServiceLogic
Services PlaneIN Service LogicAAA Number/Address Resolution
CallLogic
Call Control Plane
Signaling and Call ControlService Access FunctionSwitch-Based Service LogicEnd-to-End Voice Services
SwitchingLogic
Connection Control PlaneConnection NegotiationTranscodingBearer SwitchingMedia Control
Open,Standandard
Interfaces
Open,Standandard
Interfaces
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 8
OPT Connection Control Plane
Packet Voice Bearer Switching and Transport Technology
SwitchingLogic
Connection Control Plane
Connection NegotiationTranscodingBearer SwitchingMedia Control
Switches, Routers, Gateways, Access Servers
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 9
Voice Packetization
DSPG.711
Analog Digital
(Predigitized)
Compressed Packetized
L3 L2
Reverse Process
Packet Transport
IP Network
Sampling (PAM)
Companding (A-Law, Mu-Law)
PCM Coding (PCM G.711)
G.726 ADPCM
G.728 LD-CELP
G.729(AB) CS-ACELP
G.723.1 ACELP/MPMLQ
VoIP (ovL2)
VoATM
(VoFR)
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 10
Voice Encapsulation over IP
� Designed to carry real-time traffic on top of IP
� Real-Time Protocol (RTP)—media
� Real-Time Transport Control Protocol (RTCP)—form of signaling between RTP termination points
Watches the quality of underlying infrastructure
� RFC1889 and 1890
RTP
RTCP
Voice Payload RTP UDP IP
Variable 12 8 20
L2
Cisco IOS® RTP UDP Port Range= <16384–32768>
Four Ports Dynamically Allocated per Single
Full-Duplex CallEven-Numbered Ports
Odd-Numbered Ports
Routing/Addressing
Ports Multiplexing/(CRC)
Sequence Numbers
Payload Type Identification
Timestamps
IP Network
Cisco IOS Voice Gateway
Cisco IOS Voice Gateway
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 11
Voice QoS Network Requirements
� Low delay
Long delays cause the listener to start to talk before the speaker is finished
� Low delay variation (jitter)
Jitter causes gaps in the speech pattern that cause the quality of voice to sound “jerky”
� Low packet loss
Packet loss causes voice to sound “jerky” and annoying
� Low echo
Listener annoyed by hearing the speaker twice phase-shifted
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 12
OPT Call Control Plane
H.323 SIP MGCP
Call Control and Signaling Equipment
Gatekeeper
Media GatewayController
SIP Server
GK
CallLogic
Call Control Plane
Signaling and Call ControlService Access FunctionSwitch-Based Service LogicEnd-to-End Voice Services
Softswitch
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 13
One logicalVoIP Gateway
Softswitch Signaling Architecture
Media Gateway
Media Gateway
Signaling Gateway
Signaling Gateway
Media Gateway
Controller
Media Gateway
ControllerMGCMGCGlobal Signaling
Signal Backhaul M
edia GW Control
Media Gateway
Media Gateway
Media Transport
PSTN Signaling
PSTN Bearer s
SIGTRAN MGCPH.248
SS7ISDNQ.Sig
T1/E1/PRIE&M
FXS/FXO
RTP/UDP/IPATM
AAL1,2,5
H.323SIP
ISUP/TCP
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 14
MGCP Architecture
Residential Gateway
Access Gateway
TrunkingGateway
Media Gateway Controller
C4/C5
IMTsFXS
PRI
AnalogPhone
PBX
SS7 Link
SS7 Link
MGCP
SS7 Q.931
PacketNetwork
RTP STP
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 15
Scope of H.323 Standards
Video CodecH.261, H.263
Call Control
H.225.0
System Control
Receive
Path
Delay
(Sync)
Audio Codec
G.711, G.722,
G.723, G.728,
G.729
RAS ControlH.225.0
UDP
H.245 Control
H.225
Layer
RTP
RTCP
TCP
UDP
IP
Audio I/O
Equipment
User Data Applications
T.120 etc.
System ControlUser Interface
Video I/O
Equipment
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 16
H.323 - Signaling Call Flow
H.323 VoIP NetworkH.323 VoIP Network
RTP / RTCP StreamRTP / RTCP StreamRTP / RTCP Stream
Setup
Call Proceeding
Alerting
Connect
H.225
(TCP Port 1720)
H.245 (Dynamic
TCP Ports)
Media (UDP)
Capabilities Exchange
Open Logical Channel
Open Logical Channel Acknowledge
Gatekeeper
Calling Party
PSTN
Called Party
PSTN
SignalingSignaling
MediaMedia
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 17
Cisco Multiservice IP-to-IP Gateway
� Reliable Billing
� Network Privacy and Security
� Call Admission and Routing Control
� Protocol Inter-working
• A new VoIP product to serve as a network demarcation pointnetwork demarcation point for:
323 - 323323 - 323
323 - SIP323 - SIP
SIP - SIPSIP - SIP
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 18
IP
A
Enterprise #1
Where VoIP Networks Interconnect
SMB
SP 2
GK
Call Control Server Farm
MGX, AS5000XM
PSTN
Residential Users with Linksys CPE
LI CollectionFunction
LI AdministrationFunction
Rich Media Inter-EnterpriseVoIP PSTN Hop-OffResidential with LawfulIntercept
MGX, AS5000XM
Protocol IWF, NAPT, VPN Interconnect, Security, QoS, SLA, Topology Hiding CAC, Transcoding
SBC
SBC
SBC
Protocol Translation, Topology Hiding, Security, Transcoding,
CCM Interworking, RSVP Proxy
SBC
SBC
SBC
Protocol Translation & interworking, Transcoding, Security, Billing
SBCSBC
CSCP
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 19
� SIP is an application layer control (signaling) protocol for creating, modifying and terminating multimedia sessions with one or more participants
� SIP entities can communicate via unicast, multicast, via a mesh of unicast relations or a combination of these
� SIP is using UDP, TCP, SCTP or TLS over TCP in IPv4 and IPv6 environments
Session Initiation Protocol
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 20
SIP Components
SIP User
Agents
Registrar RedirectLocation
Database
SIP Proxy
SIP
Servers/
Services
REGISTER“Here I am”
INVITE
“I want to talk to another UA
Proxied INVITE
“I’ll handle it for you”
“Where is this
name/phone#?”
3xx Redirection
“They moved, try this address”
SIP User
Agents SIP-GW
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 21
SIP Addressing
� Fully-Qualified Domain Names (FQDN)
sip:jdoe.cisco.com
� SMTP-style Domain Names [RFC 2368]
� E.164 style addresses [RFC 2806]
sip:[email protected]; user=phone
user=phone means this is a gateway
(gateway.com is the FQDN of the egress IP gateway)
� Mixed addresses
sip:[email protected]; user=phone
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 22
General SIP Packet format
IHL Total Length
Identification Flags Fragment Offset
Header ChecksumProtocolTime to Live
Source Address
Destination Address
PaddingOptions
Version DSCP ECN
IPv4 Header is 20 Bytes
and Binary
Source PortSource Port Destination PortDestination Port
ChecksumChecksumLengthLength
UDP Header is 8 Bytes and Binary(Layer 4 here could also be TCP or SCTP)
SIP Headers in US-ASCII(variable in length per header/per message)SIP Header is Text-based
and variable in length
SIP messages *sometimes* have a message body- a SIP message header indicates the type of body- could be text, data, audio, video or something else
SIP message body is also
variable, but not always
present (depending on
the Message-type)
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 23
Jam
es P
olk
20
05
05
03
Call Forking Flow
Invite
Invite
Alice
OfficePhone
OfficePhone
Bob’s
CellphoneCellphoneBob’s
- Biloxi.com Proxy Server is “Transaction Stateful” in order to properly generate Cancels
- If the Proxy is also “Dialog Stateful”, it will receive BYE Request from Alice or Bob
Invite
Invite Invite
Atlanta.com Biloxi.com 180 Rin
ging
180 Ringing
180 Ringing
200 OK
180 Ringing
200 OK
ACK 200 OK
Session Established
CANCEL
CANCEL
RFC 3261
Mobile LaptopMobile LaptopBob’s
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 24
Current Cisco SIP Product Portfolio
IP Phones
ATA 186Linksys
PIX Firewall(& IOS FW and NAT)
Load Balancer
Cisco SIP Proxy ServerCisco CSCP
Media Gateways
Softswitch(PGW2200 & BTS 10200)
Unity CPE (CCME, SRST, Unity Express)
Meeting PlaceDynamicsoft
Service Engines
Cisco CallManager
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 25
OPT Services Plane
� IN Services
� Unified communications
� IP contact centers
� Calling card
� Debit card
� International callback
� Operator services
� Directory assistance
� Lawful intercept
� Single number
� Billing/radius
� Web-enabled services
TCAP/INAP GKTMP SIP (J)TAPI SMDI
Open Standard Interfaces
ServiceLogic
Services PlaneIN Service LogicAAANumber/Address Resolution
Enables Innovative Services
DBDB
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 26
Packet Transit
� Packet network used for simple minute transport
� Investment in packet technology rather than TDM technology for “future proofing” and network utilization
SS7 SS7
PSTNPSTN
IP Network
RTP or PVC/SVC
Local/Transit
Exchange
MG
SLT SLT
MG
PSTN Gateway
MGC MGC
MGCP MGCP
Inter-MGC
Local/Transit
Exchange
SS7SS7
STPSTP
STPSTP
STPSTP
STPSTP
PSTN Gateway
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 27
EISUP
PSTN Gateway to H.323
� PSTN gateway faces PSTN—circuit to packet gateway
� SS7 interworking function to H.323
ITSP UsingH.323
RTP
H.323
H.323
H.323
GatekeeperNative H.323 Endpoints
CiscoCallManager
H.323 Gateways
RTP
MGCP
IP Network
SS7
PSTN
Local/Transit
Exchange
MG
PSTN Gateway
MGC
STPSTP
STPSTP Adjunct
SLTSS7
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 28
SS7
PSTN
Local/Transit
Exchange
MG
PSTN Gateway
MGC
STPSTP
STPSTP
PSTN Gateway to SIP
� PSTN gateway faces PSTN—circuit to packet gateway
� SS7 interworking function to SIP
SIP
SIP
SIP Proxy
ITSP UsingSIP
SIP Gateways
Native SIPEndpoints
SLTSS7
RTP
RTP
MGCP
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 29
PGW 2200PGW 2200
SIP Proxy ServerAS5X00AS5X00
MGCP
SIP
SS7 IMT
AS5X00AS5X00
PSTN
Accounting
ETTxxDSL
Cisco ATA
V V
V V
Cisco End to End Solution
B2 Bredband AB is a market leader in the area of broadband communication in Sweden and offers fiberto the building, LAN-Ethernet and DSL broadband services to households and small companies. It reached the goal to create the worlds first genuine two-way broadband infrastructure with access to data, voice and video.
The company is present in Sweden and Norway.
B2: PSTN Gateway to Residential Broadband
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 30
Residential Voice over Broadbandwith Cisco BTS 10200
Reference Transport Infrastructure
IP Network
PSTN
Broadband Network
Residential
GW
RTP/voice
VoIP Infrastructure
AnalogPhones
MGCP/SIP
PSTN
IMT
MGCPCisco
Softswitch
Softphone
IP
phone
ETTx, DSL, Cable
AS5000,MGX8000
Intelligent
NetworkLocal Number
Portability
Lawful
InterceptionBilling Advanced
Services
SS7
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 31
Cisco Solutions Architecture Integrated Broadband VoIP Services
AGGREGATIONCPE CORE
12K/CRS-1
Media Server
Network resourcesNetwork resources
7600
TRUNKING
MGX 8000ESR10K
PRIE1/PPP
IAD
AnnouncementServer
LIServer
BRI/PRIAggr. Router
CPE
DSLAM
HFC Plant
uBR7246/uBR10012
MTA / EMTA / SMTA BTS10200
UM Server
SS7 Cable
DSL
RKS Server
LL
ITP
IVR Server
ATA188Linksys
Catalyst
ETTx
V V
V
V
PGW2200
PSTN
CallCall ControlControl
IP
Backbone
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 32
VPN VPN
Docsis
SP VoIP Architecture
SoftswitchBTS10200
PSTN
SPA
Management and Self-Administration
ITP
PSTN GatewayPGW2200
VM / UM
Lawful Interception
DHCPTFTPDNS
SS7
CME
MGX8880VXSM
SIP
SCCP
SIP
MGCP
SIPSIGTRAN
AAA
STP
SIP
SAP
SAP
Firewall Internet
V V
ATA188
SIP
SBC
MGCP/NCS
CMTS
PBX
CMTS
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 33
Cisco SP BVS SolutionEnabling a Portfolio of Business Voice Services
Customer
Options
Service
ProviderServices
Remote IP Phones with Hosted IP-PBX
Managed Cisco CCME IP-PBX
SP BVS Infrastructure
SP BVS Infrastructure
Site-to-
Site Voice
SiteSite--toto--
Site VoiceSite VoicePSTN
Access
PSTNPSTN
AccessAccessEnhanced IP Services
e.g. XML, Video, IP Conferencing
Enhanced IP ServicesEnhanced IP Servicese.g. XML, Video, IP e.g. XML, Video, IP ConferencingConferencing
Unified
Communications
UnifiedUnified
CommunicationsCommunications
Managed VoIP GW with
TDM-PBX
Managed Cisco IP-PBX
A
Managed IAD w/ Analog Phones
Business
PhoneServices
BusinessBusiness
PhonePhone
ServicesServices
CallAccounting
CallAccounting
PSTNConnectivity
PSTNConnectivity
Regulatory
LNP, LI
Regulatory
LNP, LISecurity,
QoS
Security,
QoSScalabilityScalabilityCall
Routing
Call
Routing
BVSM - Business Voice Services Management
iBVS Platform
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 34
Multitenant iBVS Architecture
VV
V V
VV
V V
Business Voice
Services Manager
Business Voice
Services Manager
VOSSManagerSystem Management
VOSSManagerSystem Management
RDBMS &LDAP Directory
BVSM
PGW2200
HSI / GK
VM /UM
DHCPDNS
BAMS /
CNRCiscoWork
s
AS / MGX / SLT / ITP
CCM Cluster
PIX / FWSM
GKGK
GKGK
SS7PRI
ISDNQ.SIGDPNSS
SCCP SCCP
SCCPMGCP
MGCP
MGCP / SCTP
FTP SIPH.323
Customer 1 Customer 2 Customer 3
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 35
Next Generation IMS Architecture
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 36
IP Multimedia Subsystem (IMS)
� IMS is a framework, a concept and an architecture –NOT a protocol
� SIP is a Signaling protocol (RFC3261 and derivatives) which was adapted by 3GPP and 3GPP2
� 3GPP named SIP interface to the application layer in IMS by the letters ISC (IMS Service Control)
� ISC is one of the three pre-requisites for IMS (together with HSS and CSCF(s)) – as was defined lately in an interesting report by HeavyReading
� Yes – SPs can deploy SIP without IMS
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 37
IMS Basic Architecture Components
IP Core
HSS
ISC
Cx
Application Layer
Control Layer
Transport Layer
PSTN / PLMN
Media Gateway
Control Function
(MGCF)
Media Gateway (MGW)
H.248
SIGTRAN
SIP
Breakout Gateway
Control Function (BGCF)
Media Resource Function
Controller (MRFC)
Media Resource Function
Processing (MRFP)
Other VoIP
H.248
Application Server (AS)
Call Session
Control Function (CSCF)
Home Subscriber
Server (HSS)
and Subscriber Location
Function (SLF)
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 38
IMS based Services
� Push to Talk
From a Buddy List user interface select one or more users with whom to have 1 way, streamed, individual/group conversations like with CB Radio.
� Push to See
While in Circuit Switched conversational voice use your phone user interface to trigger Live video to the person you are talking to.
� Rich Voice
Enrich the Circuit Switched voice experience by providing a presence enabled Buddy List and network based address book from which conversational voice and other multimedia services can be launched.
� Peer to Peer Gaming
� Collaboration
The ability to share multimedia and applications while in a voice/video call.
Copyright © 2005, Cisco Systems, Inc. All rights reserved. Printed in USA.Presentation_ID.scr
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 39
High Level Target IMS Architecture
© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 40
Q and A
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© 2006 Cisco Systems, Inc. All rights reserved. Cisco ConfidentialPresentation_ID 41