1. Software interoperability in the NGN Service layer
Presentation Title
Software interoperability in the NGN Service layer
Dave Penkler
CTO OpenCall, HP
Copyright © 2003 HP corporate presentation. All rights reserved.

2. Presentation Outline Why Software Interoperability for NGN
Presentation Title
Why Software Interoperability for NGN
Preliminaries
NGN Service layer
Software Portability versus Interoperability
Protocols versus API’s
APIs and Protocols in the service layer
Conclusion
4/21/2019 HP
Copyright © 2003 HP corporate presentation. All rights reserved.

3. Why Software Interoperability for NGN
Interoperability from the user’s perspective:
Ability to create, use and share information and services on different devices with software from different vendors over multiple networks and service providers.
The value is in the applications
Application innovation happens elsewhere:
Standard developers can hardly anticipate all useful applications and business models
The cost, complexity and delay incurred by striving for convergence at the protocol level will likely kill aspiring NGN business cases.
Programmability of the network = Application innovation for NGN
Clear separation of network and application functionality
Defining abstractions of network capabilities as software interfaces
The interface specifications are open and implementations testable for interoperability
Software functions can be invoked transparently across the network
Restore end to end transparency: protocol & SW interoperability
4/21/2019 HP

4. Common Service Infrastructure
Presentation Title
Next Generation Network Architecture
Common Service Infrastructure
(e.g. IMS)
Adapted from ITU-T FGNGN-FRA
Service stratum
Network
Application
Interface
Application Functions
Service
User
Profile
Functions
Network
Resources &
Capabilities I/F
Service and Control
Functions
Management Functions
Transport
User
Profile
Functions
Network
Transport Control
Attachment
Media
Functions
Control Functions
Handling
Functions
Customer
Gateway
Other
Other
Functions
Functions
networks
networks
Access
Access
Access
Transport
Edge
Core Transport
Core Transport
Functions
Transport
Functions
Functions
Functions
functions
functions
UNI
NNI
Transport stratum
Control
Transport Network
Independence
Access Network
Independence
Media
Management
4/21/2019 HP
Copyright © 2003 HP corporate presentation. All rights reserved.

5. Software Portability vs Interoperability
Code that can be deployed and executed on different systems with the same behaviour
Source code: portability ensured by compiler and libraries
Binary code: portability ensured by application binary interface
Network code: (Code that can be sent over a network and executed at the destination) portability ensured by run-time environment (eg: Java, ECMAscript, XML scripts)
Software interoperability
Code developed to one side of an interface specification that can interact as expected with heterogeneous implementations the of the other side either locally or remotely.
4/21/2019 HP

6. Application Programming Interfaces vs Protocols
NGN supports the delivery of end-user services through application servers, rather than directly embedding services as capabilities in the control protocols
Protocols define what bits are sent on the wire between 2 entities – Technology neutral.
APIs are defined in terms of the operations and data-structures exchanged between 2 software entities either locally or remotely.
API’s are implemented as a service interface to protocols or as a higher level interface usefully combining a number of lower level or remote peer functions.
Applications interact with users, network resources and with one another through API’s
NGN and IMS standards development is primarily done at the protocol level.
Adopting all IP and IETF protocol standards is not enough to enable end to end network transparency.
SIP protocol specs for IMS are already horribly complicated
Web Services: A viable technology neutral way to define interfaces and achieve software interoperability over the network.
4/21/2019 HP

7. API complexity trade-off
Remote
Invocation
Application
Level of Abstraction
Level of
Expressivity
of API
Number of Programmers
Application
Programming
Simplicity
Implementation
Complexity of
API
Service
Enabler
API
Application
Function
Service
Building Block
API
Middleware
High Level
Protocol API
Low Level
Protocol API
Protocol
Implementation
Transport
Network
Functions
4/21/2019 HP

8. APIs and Protocols in the Service Layer
External ASPs &
IT services
Applications in service provider and terminal domains
Network applications and capabilities, exposed via XML and Web Service
interfaces (e.g. ParlayX, OMA web services).
Interactive
Voice & Video
Applications
Instant Group
Communication
Applications
Next-Generation
Messaging
Applications
Frameworks
for
Network
Applications
Network Application
Layer
service provisioning and management
Common frameworks for
Network Resources & Capabilities exposed as API’s or protocols
Media Processing,
Media Control,
Media Storage
Identity
Management
Authentication
Authorisation
Subscriber
Profile
Management
Billing
&
Rating
User Information
Management
(presence, contact
list, location)
Device
Capabilities
Resources
Network
IMS Core Network
Circuit Switched
Core Network
Packet Switched
Core Network
Network
Core
4/21/2019 HP

9. Conclusion
To enable innovation the NGN must be programmable from the edge.
Expose network resources, capabilities and applications as standard API’s
End to end network transparency
Simple protocols
Facilitate protocol and software interoperability
User expects things to work the same everywhere
Software interoperability is key
necessary but not sufficient
4/21/2019 HP

10. Presentation Title 4/21/2019 HP
Copyright © 2003 HP corporate presentation. All rights reserved.