An IPX hub is designed to be a secure, commercial-class environment for voice and media exchange over IP, and to link telecoms service providers, including fixed and mobile operators, content providers, internet service providers and others. The current focus of IPX will be on enabling seamless, national and international roaming for voice services, SMS and multimedia messaging. IPX hubs will also provide interoperability between different networks and platforms such as interworking between instant messaging (IM) and SMS. And as demand among the user community for multimedia services grows, the IPX hub will evolve to support IMS-based multimedia communications, like those enabled by the rich communications suite (RCS). In the future, the IP proxy model will enable roaming and interconnect of IMS traffic, which will be driven by the migration to all-IP radio access networks as new IP-based technologies such as HSPA(+) and LTE become much more widely implemented.
How does IPX differ from IP?
IPX differs from the standard IP interconnect in a number of ways. First of all, as the IPX hub is not addressable from the internet, it provides a more secure peering environment than standard network-to-network IP peering. Secondly, the IPX hub provides a standards-based, reduced-error environment for communications that enables multilateral peering with more providers.
Perhaps most importantly, the IPX is designed to provide a commercial-grade environment that facilitates quality of service assurance and cascading billing payments with multiple peers and across multiple service and pricing levels. The ability to prioritise high-quality services like voice and video in favour of less demanding SMS or instant messaging, enables providers to meet service level agreements (SLAs) and deliver superior customer service, even when bandwidth is limited during peak usage periods.
Of equal importance for service providers is the ability to track cascading payments involving multiple service providers in the IPX hub. Service providers can leverage multilateral agreements or develop their own bilateral agreements between peers to create individual pricing and billing structures for the services that they purchase and sell, then track them more easily.
As demand for complex user interactions involving multimedia content, location-based and Web 2.0 services potentially from multiple different players (ASPs, mobile operators, app stores), this will become especially important.
What is driving the move to IPX?
End-user demand for mobile broadband is growing rapidly and more roaming users are therefore requiring an IP interconnection to their home network. At the same time, mobile network operators are migrating their networks to IP infrastructures. IPX therefore enables traffic to go seamlessly from traditional TDM to VoIP and SMS all over the same IP network.
IPX also enables operators and service providers to accommodate new services, such as the GSMA’s rich communications suite – an industry recommendation for the delivery of multimedia services. RCS can enhance the existing mobile phone capabilities, by enabling different types of communication such as live video streaming. The globalisation of RCS will be possible with IPX interconnection, as these multimedia services require an IP connection end-to-end.
The cost reduction argument
IPX also helps to reduce costs, providing an end-to-end IP network, which facilitates guaranteed SLAs from the hub operator and significantly reduces the cost of traffic going forward. Complete IP-to-IP peering provides a secure and effective border which is estimated to be five to 10 times less costly than converting the traffic at the gateway.
The ongoing operational cost of the network is also significantly lower as the network requires less equipme nection. Until such standards are agreed however, operators should look for the following six characteristics of a multilateral peering environment when considering an IPX interconnect solution: security, interoperability, quality of service, billing models, routing services and scalability.
