Transcript SP-7 - TMCnet

Leveraging SS7 to Deliver IP Services
Carl Bergstrom
Director – IN & IP Services
VeriSign Telecommunication Services
Internet Telephony Conference, February 6, 2003
1
VoIP’s Impact

VoIP’s most significant impact is from the separation of
session (call control) knowledge from the Network
Elements involved in call transport.
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–
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Unbundled transport and application layers
Services reside outside of switches
Commodity components
“Infinite” scalability
Where does the Intelligence go:
the Network or the Edge?
2
Open Telephony Architecture
Services Plane
Service
Logic
IN Service Logic
AAA,
Address Resolution
Call Control Plane
Signaling and Call Control
Service Access Function
Switch-Based Service Logic
End to End Voice
Call
Services
Logic
Interworking
Tool Set
Definition
Conversion
Simulator
Configuration
Analyzer
Connection Plane
Switching
Connection Negotiation
Transcoding
Logic
Bearer Switching
Media Control: SIP, H.323, PNNI, etc.
3
OSS
Billing
Net. Mgt.
Fault Mgt
Service
Provisioning
Cust.
Provisioning
Service Innovation
The Value of SS7

SS7 is still a significant component of telecom networks
– The U.S. SS7 network handles about 15 billion ISDN User Part
(ISUP) messages a day
– About 2B TCAP queries transverse SS7 databases each day

Circuit switches are not going away anytime soon
– Pure softswitch networks have been slow to evolve
– Carriers want solutions that leverage existing investments
– Access side of the network will remain PSTN until significant issues
are resolved:
Emergency services
 Reliability
 Feature transparency
 Calea, LNP, other regulatory issues

4
The SS7 network is the largest transaction
network in the world.
Phases of Network Evolution
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
Phase 1: Transport Cost Optimization

Phase 2: New Revenue Generation

Phase 3: Converged Multi-Service Access Networks
Phases of Network Evolution
Softswitch/
Signaling Gateway
SS7/
HLR
•
ISUP/TCAP/
MAP
ISP
PSTN
(Wireline/
Wireless)
Gateway/
RAS
Packet
Backbone
PBX
Enterprise
6
Gateway/
RAS
Phase 1: Transport cost
optimization
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Data Offload
Tandem Offload
Wireless Tandem
Leveraging AIN services
Converged Transport
Co-existence of TDM and
IP networks
Transport Cost Optimization:
Data Offload

Significant cost savings for dial-up sessions
– Use of Inter-machine Trunks (IMT) instead of Primary
Rate Interface (PRI) connections can realize average savings
of 50%
– Relieve switch congestion and reduce need to add switch
port capacity

7
Softswitch provides SS7 call set-up and SS7 to IP
conversion
SS7 Eliminates Network Congestion
STP
POTS or ISDN Access Lines
SSP
Interoffice Trunks
Data Trunks
Tandem
Switch
Network
SSP
SSP
SSP
SSP
Softswitch
8
 1998, Cisco Systems
Internet
Service
Provider
Transport Cost Optimization:
Tandem Offload
•
Required routing functionality
– Custom dialing and routing
plans
– LNP support
– Toll-free (8xx) routing
– Voice VPN support
– Local, intra-LATA and interLATA call routing
– International call routing
– Feature Group D services –
carrier selection
– Operator & directory
assistance
– Least cost routing
Softswitch/
Signaling Gateway
SCP
TCAP/SIP
SS7
SS7
MGCP
MGCP
IP/ATM
Network
PSTN
PSTN
IMT/
PRI
Media
Gateway / RAS
IMT/
PRI
RTP VoIP
PRI
PBX
Enterprise
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PSTN
Media
Gateway
Co-existent Networks /
Leveraging AIN Services
SCP
SCP
8XX
CNAM
LIDB
LNP
WIN/AIN
SCTP
SCP
SG
AS
AS
TCAP
SS7
SCTP
Softswitch/
SIP
Signaling Gateway
STP
SCTP
SIP+
IP
Network
SS7
IMT
H.323
Q.931
H.225/RAS
H.245
TRIP
H.225
Gatekeeper
SSP
Media Gateway
10
SGCP
MGCP
H.248
MEGACO
SIP
Proxy
SIP
SIP
SIP
Phases of Network Evolution
SIP/H.323/
JAIN
Application
Server
SS7/
HLR
SIP/H.323/
JAIN
Application
Server
Softswitch/
Signaling Gateway
•
–
–
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–
–
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ISUP/TCAP/
MAP
ISP
Gateway/
RAS
PSTN
(Wireline/
Wireless)
Gateway/
RAS
•
–
–
SIP
PBX
2G/2.5G
•
3G
Enterprise
PBX/
Key System
11
–
RNC
Enterprise/SMB
IAD
IAD
Out of region voice+data service
delivery
Peering/Inter-working with H.323 &
SIP Networks
Integration of best in Class
Application Servers
Enhanced Services for Businesses
Phase 3: Converged Multi-Service
Access Networks
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Residence
Data Offload
Tandem Offload
Wireless Tandem
Leveraging AIN services
Converged Transport
Co-existence of TDM and IP
networks
Phase 2: New Revenue generation
–
H.323
Packet
Backbone
Phase 1: Transport cost
optimization
Wireline / Wireless/ TDM/ ATM/ IP
networks
Business, Residential & Wireless
end-user segments
Ubiquitous service delivery via
common infrastructure