Building Applications Using SIP
Scott Hoffpauir
Vice President, Engineering
Fall 1999 VON, Atlanta
Baseline Architecture
Media
Gateway
Controller
Proxy / Redirect
Server
SIP
MGCP
Call
Management
System
SIP
SIP
MGCP
Packet Network
MGCP
SIP
MGCP
Media Gateways
User Agents
Multimedia Terminal
Adapters
Centralized
architecture for trunks
and signaling links
Distributed
architecture for
intelligent endpoints
Centralized
architecture for
residential phones
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Components
?
Enhanced Services
Media
Gateway
Controller
Proxy and
Call
Redirect Management
Server
System
Media
Gateway
Multimedia
Terminal
Adapter
Client
Phone




Basic Call Control
Authentication and Security
Billing
Bandwidth Management
 Packet Interface
 Signaling Interworking
 Media Transcoding
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SIP Application Server
SIP Proxy and
Redirect
Server
Enhanced
Services
Management
Application Server
Call Server
Feature Server
Web Server
Media Server
Enhanced
Services
Execution
Conferencing,
IVR
Resources
Using SIP, enhanced services, which
reside on an application server, are
separated from basic call functions
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Application Server Connectivity
Email
Servers
Application
Server
Directory
Servers
Media
Servers
Web
Servers
Media
Gateway
Controller
Call
Management
System
SIP
SIP
MGCP
SIP
Proxy / Redirect
Server
SIP
MGCP
Packet Network
MGCP
SIP
MGCP
Media Gateways
User Agents
Multimedia Terminal
Adapters
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Technology Convergence
Interactive
Voice
Response
Multimedia
Record &
Playback
Text to
Speech
Multimedia
Conferencing
Personal
Information
Managers
Unified
Messaging
Application Server
Directory
Services
Wireless PDA
Cable Set
Top Boxes
SIP
Billing
Systems
Multimedia
Streaming
OAMP
Web Browser
Communication Entities
Application servers provide a platform for integrating telephony
services with Internet, messaging, devices, and OAMP services
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SIP as an Enhanced Services Protocol
 Open, simple, extensible, and lightweight
protocol
 Internet heritage – easier to integrate with
telephony and Internet functions
 Already implemented or planned on most
softswitches and gateways
 Allows control of bearer path
 Supports multiple call legs (i.e., forking)
 Same protocol used between services and call
control entities
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Service Possibilities
Basic Call Control
Application Server
Invite
3XX Redirect
Basic Call Control
Application Server
Invite
200 OK
Basic Call Control
Application Server
Invite
Invite
Routing Services
Media Manipulation
Services
Event Notification
Services
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Service Execution
Screen out
900 and
976 Calls
To: Bob Smith
3019774295
Collect 4
Digits and
Validate PIN
Log call
attempt
Barring
Service
Directory
Service
PIN
Service
Logging
Service
Application
Server
Execution Environment
SIP
I/F
Media
Gateway
Controller
LDAP
I/F
IVR
I/F
Email
I/F
Retrieve
Directory
Information
Play Tone
Collect
DTMF
Send
E-mail
Invite
Invite
Call
Mgmt
System
Packet Network
Media Gateways
Multimedia Terminal
Adapters
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Summary
 Enhanced services are key to the success of
packet telephony
 SIP application servers can be used to augment
entities providing basic call control functions
 SIP application servers can be used across
different architectures (H.323, MGCP)
 SIP is a simple, open, and well-defined
interface encouraging third party application
services and vendor independence
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BroadSoft
Company
• Founded September 1998, in Gaithersburg, Maryland
Objective
• Deliver an enhanced services creation software suite
to service providers
Product
• Service execution, management, and creation
platform for broadband packet communications
networks
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Building Applications Using SIP
Scott Hoffpauir
BroadSoft, Inc.
200 Perry Parkway, Suite 1
Gaithersburg, MD 20877
(301) 977 4295
www.broadsoft.com
scott@broadsoft.com