LTE drives interest in IP Exchange

Figure 1: Best describes an IPX platform (Source: Telecom Asia)Operators are starting to prick up their ears at mention of IP exchange (IPX), as IP core networks become the norm and looming mass market LTE services make adoption of the GSM Association-defined traffic exchange mechanism a more urgent concern. However, carriers say more clarity over what constitutes an IPX network and the service-level-agreements that underpin them is needed before the market can truly take off.

Almost two-thirds of global operators plan to deploy IPX services in the next one to three years, with the shift to LTE a major driver of interest in the exchange networks, research by Telecom Asia reveals.

The study - conducted for IPX provider Sybase 365 - found that 63% of global carriers plan to launch the networks within three years, with the majority believing the networks will become an essential component to offering LTE services during that period. Factors turning operators on to IPX include the security, ease of deploying end-to-end IP services, promises of lower costs, and the potential to ease the migration to next-generation networks.

More than 50% of the operators surveyed rated all the elements as key benefits of IPX currently, however, a breakdown of the numbers shows that many operators see the ease of IP deployment element as the chief purpose of IPX (see Figure 1).

While IP deployment and service quality top the list, carriers are also attracted by the potential to lower costs using IPX. Justin Middleton, intercarrier commercial manager at Vodafone Hutchison Australia (VHA), explains one of the main cost saving measures is reducing the number of IP exchange hubbing partners from the 10-12 VHA has currently, to potentially just one. "I'm curious to see what results we'll derive from that," he notes.

Despite the current benefits, it is for LTE networks that IPX holds the greatest appeal. There is a clear correlation between the number of operators planning to deploy IPX in the next three years and those that consider the networks essential for LTE services. And many operators also see the exchange networks as a means to shore up relationships with fixed-line carriers and over-the-top service providers.

Relationship building aside, operators rank roaming, IP signaling and streaming as the principal services IPX will bring to next-generation networks. In the longer term, they will also expect their IPX to handle fraud detection.

Paul Hodges, executive VP of corporate, wholesale and international at Hong Kong-based CSL, believes it will be up to IPX carriers to implement the new services offered by the networks. His view is echoed by Bernd Hoogkamp, mobile data sales manager at TeliaSonera's international carrier division, who says his firm will expect the IPX to offer new services rather than build services to suit the new networks.

Figure 2: Operator deployments by carrier type (Source: Telecom Asia)IPX today

All the talk about the future potential of IPX overshadows the fact that 34% of carriers surveyed have already deployed IP exchange networks. The networks are currently most popular among integrated operators, followed by wireless providers and wholesalers (see Figure 2).

However, these early deployments have flagged some problems in terms of implementing IPX - not least of which is whether current networks truly live up to the GSM Association's definition of an IP exchange.

At its simplest level, IPX is the modern version of the GSMA's GPRS Roaming Exchange (GRX) specifications. The association has laid out common specifications for the end-to-end delivery of IP traffic and the quality of service operators can expect, but it has left the market to decide how to implement those specifications.

CSL's Hodges notes the specifications are necessary, particularly for the data roaming traffic that is expected to dominate early IPX deals. "When you are talking about data speeds up to 100 Mbps, without guaranteed quality of service in the underlying MPLS network, the connectivity we are used to such as the conventional GRX simply would not be able to support this kind of data speed."

The problem, though, is a lack of clarity on how to achieve the service level agreements (SLAs) that underpin IPX, Hodges notes. He says defining SLAs covering Diameter and SIP proxy, and voice hubbing have "yet to be clearly defined in the IPX ecosystem."

Despite that lack of clarity, Hodges says the main hindrance to IPX deployment currently is a lack of compatible networks to hook up with. "For basic IPX data connectivity, we're ready now. The schedule for implementation of other services such as voice and signaling largely depends on the readiness of other mobile operators."

Assessing that readiness is one of the major stumbling blocks to IPX currently, says Telia Sonera's Hoogkamp. He notes the phrase has become another industry buzzword, which makes it hard to assess which carriers are ready to roll. "A lot [of carriers] have an IPX, but how do you assure end-to-end quality of service?"

The uncertainty makes Hoogkamp wary of Asia-Pacific operator's claims to have launched high-level IPX networks covering end-to-end service delivery, and he says more specific regulations are needed to clarify the situation.

Hoogkamp's views are not shared by the GSMA. Dan Warren senior director of technology at the association, stands by the view that it is for the market to decide how interconnection works, noting that IPX is similar to the GRX agreements already in place for GPRS traffic. As such, no new standards should be needed to cover the in-depth details of commercial agreements, he says.

Mitigating the potential spat is Mark Dioguardi, executive VP and head of network and technology at Maxis. He told Telecom Asia the solution is for operators to agree a clear implementation strategy for IPX. "The challenge is in working closely with different vendors to establish the full range of possible benefits which stem from IPX's current applications, while assessing the need for a certain amount of investment in things such as session border control equipment."

While LTE interconnect may currently be hindered by small number of 4G networks, Deutsche Telekom spokesman Ralf Sauerzapf says that doesn't stop IPX being a commercial reality. "IPX transport is a reality today and will increase with RCS-e and Diameter signaling over the next 12 months."

Warren concedes "some technical work" is necessary for future and emerging services, including RCS-e and VoLTE, to ensure "operators are working in the same way." He says the association has the task in hand, and expects to finalize the work in the next six months.