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.

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.

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

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.

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

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

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

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

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

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