A Head-end solution for broadcasting IP and Pay-media Services
by Norman Lievaart

SYNOPSIS -

Most pay-media services are currently delivered to subscribers via a broadcasting infrastructure. With growing pressure on the need to contain costs, service providers are increasingly considering the benefits of distributing their services via IP networks.

Irdeto Access Conditional Access (CA) systems and scramblers are now able to support the secure, disruption-free transition in service provision, from a traditional pay-TV DVB network to a pay-media IP infrastructure.  This article describes how this transition can be achieved by implementing a convergent pay-media head-end.

INTRODUCTION

The flexibility of digital technologies deployment is introducing a host of service opportunities that include data, entertainment and telephony service delivery to clients.  The technology and business models to support each of these service types are developing rapidly. Because of the bandwidth now available to operators, they are no longer restricted to offering a single service exclusively, but can combine services to meet the needs of a broader audience.

Broadband access systems, capable of delivering a wide variety of these services, are becoming commercially realisable.  For pay-media operators, however, there has never been a simple and seamless way of simultaneously managing the entitlements to pay-media content for both existing Digital Video Broadcasting (DVB) and new Internet Protocol (IP) services.  Recent Conditional Access (CA) developments however, have realised this ideal: CA systems have become available that offer support for simultaneous DVB and broadband services throughout the operation.

DVB SERVICES

The DVB group is a market-led consortium of private and public organisations in the broadcasting industry. It was formed in 1993, with Irdeto Access as a founding member. The aim of the group was to establish a framework for the introduction of MPEG-2 based digital broadcasting services. DVB specifications can also be used for all types of data broadcasting and bi-directional communications services associated with interactive broadcasting.  DVB services are therefore essentially digital broadcasting services with provisions for interactive services and encapsulated data.

INTERNET-BASED SERVICES

The Internet is a collection of packet-switched networks that are inter-connected by routers.  Transmission Control Protocol / Internet Protocol (TCP/IP) protocols allow these networks to function as a single, large inter-connected network. The Internet is thus a global network that permits millions of computers to exchange information.

TCP/IP is now the accepted way of delivering digital data and is increasingly being used to convey voice services. The range of data services that can be conveyed over a broadband IP network is almost unlimited. Often, the initial attraction of such a system is speed and quick access to the Internet via conventional browsers.

The technology does however have potential for even wider applications: the Internet is migrating towards becoming a platform for e-Commerce for both Business-To-Business (B2B) and Business-To-Consumer (B2C) applications. These developments are likely to accelerate with the further deployment of broadband networks and advanced CA systems that can securely protect both broadcasting and IP content.

PAY-MEDIA CONVERGENT NETWORK

Advanced CA systems permit the simultaneous CA management of (existing) DVB services and (new) IP services. It is thus relatively simple to establish a convergent multimedia head-end system using the same CA server. This is a good application for broadcasting service providers who are in the process of transitioning from a DVB-based distribution topology to an all-IP distribution format.

The DVB content is scrambled and distributed in the usual manner for these types of networks.  The client device for rendering the DVB content is either a Set Top Box (STB) or a PC for rendering IP content encapsulated into DVB packets. Both the STB and the PC card require a smart card to render scrambled DVB content.

The IP content is passed through the IP scrambler for delivery by the IP network and/or encapsulation by a suitable DVB multiplexer. The client device for rendering the IP content is either an IP STB or a PC. Both the STB and the PC card require a smart card to render scrambled IP content.

In convergent head-end architecture, this type of CA system is capable of generating the required CA messages for both the DVB and the IP content. 

A CONVERGENT CA APPLICATION

Irdeto M-Crypt (100k subscriber capacity) and psys (5-million subscriber capacity) CA systems support our DVB scrambler as well as our IP scrambler, a component of our IP security solution: Irdeto CypherCast.  Each DVB Scrambler supports the scrambling requirements for one DVB transport stream, while the IP scrambler supports a throughput of 40 Mb/s in its software implementation for low bandwidth requirements. High bandwidth requirements such as IP via multiple satellite transponders, Digital Subscriber Line (xDSL), Video On Demand (VOD) or telecoms backbone delivery are supported by the IP Scrambler’s 650 Mb/s hardware scrambler implementation.

Irdeto CypherCast operates in a wide variety of environments in both the uni- and bi-directional modes. It can be used with a variety of IP processing equipment such as encapsulators, routers, broadband infrastructures, satellite receivers and cable modems.    

The addition of an IP scrambler to a pay-media operation enables the same level of security to be achieved for both IP services and DVB services.  Key product associations can be shared across the two networks. For example, if the “digital package” for video services were ordered, the associated IP streaming music channels could be encrypted with the same product keys.  When the subscriber cancels his DVB “digital package” video service, the access rights to listen to the associated streaming IP music service will also be revoked.

A wide variety of DVB STB manufacturers support the Irdeto Access CA system.  PC cards suitable for Irdeto Access’s CA system are available from BroadLogic. Irdeto Access is well advanced in integrating its CA system with IP STB’s from Amino, Hauppage, Humax, IDC and Kreatel.  Suitable IP PC cards are available from BroadLogic. Although uni-directional DVB links are shown in the diagram, return-path systems implemented with Data Over Cable Service Interface Specification (DOCSIS) or Digital Audio Visual Interactive Council (DAVIC) protocols are also possible.

The same smart card can be deployed for both the DVB as well as the IP networks, thereby offering flexibility and lower-cost solutions for deploying convergent services, compared to two separate networks. The following diagram shows an application example for a typical convergent pay-media distribution system:

CONCLUSION

Pay-media operators are moving towards offering promising B2B and B2C IP services to new and existing subscribers as part of their service “mix”. Until recently however, there was no transition mechanism that would permit these new services to be integrated and delivered over satisfactorily functioning pay-broadcasting platforms. 

New CA system products have enabled this convergent head-end ideal to be realised with relatively modest capital outlays. The Irdeto Access CA systems described permit a full range of both broadcasting and IP services to be offered to a wide variety of subscriber terminal equipment types, over a substantially unmodified distribution infrastructure. These techniques enable the pay-media service provider to take advantage of a growing trend in the industry: delivery of new and familiar services via both DVB media and IP networks.