Mobile Operators are evolving towards packet infrastructures using the GSM and UMTS air interfaces and 3G. Fixed Network Operators (FNOs) are deploying Next-Generation Networks (NGNs) and ISPs and ASPs are offering an ever-increasing range of services. The common protocol for all these networks and services is IP (Internet Protocol).

Mobile Operators are evolving towards packet infrastructures using the GSM and UMTS air interfaces and 3G. Fixed Network Operators (FNOs) are deploying Next-Generation Networks (NGNs) and ISPs and ASPs are offering an ever-increasing range of services. The common protocol for all these networks and services is IP (Internet Protocol).

All these commercial entities have the common objective of delivering traffic to each other in a profitable and cost effective way. Although these services can often be delivered via the Internet, there are issues around reliability, security and, above all, quality of service.

Service Providers are looking for an IP backbone that enables them to transfer traffic between each other under controlled circumstances, in compliance with minimum quality criteria using a business model that compensates everyone involved in delivering the service.

The IP backbone would be used to support a range of services including:

  • IP voice telephony services i.e. Voice over IP (VoIP). The voice service will be allocated a conversational Quality of Service (QoS) traffic class. Critically, tight end-to-end latency control must be maintained for voice telephony services to work effectively
  • Video telephony which, as with IP voice telephony, can originate on a circuit or packet bearer. Video telephony is a real-time service that also needs a conversational QoS traffic class
  • Push-to-talk over Cellular (PoC) that provides the ability for one person to communicate with a pre-defined list of others without the inconveniences, long set-up delays or inefficiencies of a circuit-switched conference call
  • Instant messaging (IM) between two or more people using text messages (and possibly small graphical images). IM usually relies on presence information to ensure that messages can be delivered to the recipients instantly
  • Presence that provides a way for users to communicate their status (online, offline, busy etc.) to another user or set of users
  • Video share services that allow users to share video (either live or pre-recorded) with another user, whilst maintaining a voice call

Service Providers will need to sign up to Service Level Agreements (SLAs) and Interconnect Contracts that support the following key business principles:

  • End-to-End service delivery
  • Service interoperability – universal service interworking (fixed and mobile)
  • Customer protection – against identity theft, fraud, invasion of privacy, unsolicited content etc.
  • Security, including isolating the IP backbone from the Internet
  • Service Quality: Conformance to strict SLAs defined for each service
  • Redundancy/Availability: Using alternate routing and multiple Points of Interconnect
  • Flexibility: Allow the rapid deployment of new services
  • A Billing model where the initiating party pays and cascading revenues are distributed from end-to-end
  • Value-based pricing with the ability to offer different end user prices depending on consumer preferences and quality selection

The IP backbone will support three interconnect models:

  • Bilateral – Transport Only: A bilateral connection between two Service Providers using the IP backbone Transport layer with guaranteed QoS end-to-end. Each Service Provider pays their IP backbone provider for the transport capacity, depending on the capacity and the level of QoS provided. Because the bilateral agreement is between the Service Providers, the payment of any termination charges is a matter for the Service Providers.
  • Bilateral – Service and Transport: A bilateral connection between two Service Providers using both the IP backbone Service layer and the Transport layer with guaranteed QoS end-to-end. In this case, the IP backbone provider also supplies cascading interconnect payment facilities. This enables an originating Service Provider to make a single payment to the IP backbone provider who pays the termination charge to the terminating Service Provider.
  • Multilateral – Hubbing: A multilateral connection using Hub functionality. Multilateral connectivity is where traffic is routed from one Service Provider to many other Service Providers through a single agreement with the IP backbone provider. The Multilateral Hub Service provides QoS transport and cascading interconnect payments to a number of interconnect partners via a single agreement between the Service Provider and IP backbone provider. This “one-to-many” model is operationally highly efficient for the Service Provider.

The benefits of using this “one to many” model include:

  • One commercial agreement opens connectivity and service interworking to tens or hundreds of other Service Providers
  • The ability to pass interconnect payments between the originating Service Provider and the terminating Service Provider without a direct contractual relationship between the two parties
  • Routing traffic to other Service Providers can be handled via a single route between the originating network and the IP backbone provider
  • The ability to manage and maintain an adequate level of QoS, security, anti-fraud, etc… from end to end

The challenge for the next generation of interconnect is to deliver secure, reliable and high quality services over an IP network that links fixed and mobile operators, ISPs and other service providers together. For this to work everyone involved in delivering these services must be compensated for their efforts and the mechanism for this is IP interconnect accounting.