Transcript Converged Services - Best IT Documents

Converged Services
Three Aspects of Convergence
1) Interworking of “traditional” PSTN with the IP infrastructure to support
voice over IP
2) Interworking of PSTN with the IP infrastructure to deliver IP-based
service control for “traditional” PSTN calls (i.e., IP Telephony without
voice over IP)
3) Interworking of PSTN with the IP infrastructure to provide remote
access to IP networks via PSTN lines
Adjusting the PSTN to the Internet
(PSTN access to IP networks)

Exploiting the bandwidth that can be supported by two-wire telephone
access lines
+ Pulse Code Modulation (PCM) modem
+ Digital Subscriber’s Line (DSL)
 Offloading Internet traffic from the PSTN
PSTN Congestion due to Internet Traffic
PSTN
Internet
User
Ingress
Switch
SS7
Network
Egress
Switch
Remote
Access
Server
ISP
Internet
congestion
An Internet Offload Solution
Ingress
Switch
PSTN
Internet
User
SS7
Network
Egress
Switch
Softswitch
Remote
Access
Server
ISP
Internet
Adjusting the Internet to the PSTN (two aspects)
1) Support of the IP telephony requirements:
 A new IP endpoint--IP telephony gateway--is required to interconnect
the Internet and the PSTN
 QoS must be enforced
 The IP and PSTN naming and addressing schemes must interwork
2) The Internet-based support of the PSTN services requirement:
 Keep the intelligence at the edges! (Or, at least, share it with the edges)
PC-to-PC (1)
PSTN as an access vehicle
IP Network
PSTN
Network
Access Server
dialup
access
PC-to-PC (2)
PSTN as the backbone transport
PSTN
Enterprise B
Enterprise A
IP PBX
Gateway
Gateway
IP PBX
Phone-to-PC or vice versa
IP Network
PSTN
Gateway
Phone-to-phone
IP trunking
Home
Gateway
PSTN
IP Network
Enterprise
Gateway
Gateway
Why IP telephony?

Toll bypass avoids long-distance call charges.
 One type of networks for both voice and data simplifies network
operation, administration, and management.
 Easy integration with other IP applications promises richer than ever
telephony services.
Converged IP Telephony Architecture
IVR
System
Public Switched
Telephone Network
SCP
SS7
voice
Media
Gateway
H.323
Terminal
H.248
Soft Switch
voice
SIP/H.323
SIP
User
Agent
SIP User
Agent
H.323
Terminal
Gatekeeper Cloud
SIP Server Cloud
IP Network
PSTN/Internet Interworking (PINT)
PINT
Client
Internet
PINT
Gateway
SIP
SCP
PSTN
Requests

Request to call

Request to hear content

Request to fax

Future: Request to Conference
Internet Enhancing PSTN Call Control
PINT has successfully concluded, but …
There are potential services for the future
•
•
•
•
•
•
•
•
Multimedia conferencing
Free calls (paid by advertisers)
– with the profiling feature
Speed Call list provisioning
Service Subscription
Follow-me service provisioning
Access to communications bills
Account information changes
VPN Provisioning