News

IPX: a Global, Private, IP Network for Everyone

Bob Emmerson says the title is not an oxymoron - it’s a private IP interconnection solution for fixed and mobile network operators as well as trusted service providers.

“We’ll all be using this IPX service delivery solution in future, one reason being the availability of high quality, low cost roaming. Think of it a powerful, parallel Internet. Network operators are being challenged by Internet-centric service providers like Google and Skype. On the other hand there is a huge opportunity. As indicated in an earlier article, around 5 billion people will have a mobile subscription by 2015, most of the growth coming from the emerging markets, principally China and India.

What’s needed is a way of combining the cost model of the Internet with the quality, security and reliability of a telecoms network. And that way starts by migrating network cores to IP, i.e. by using a more efficient transport mechanism in order to reduce OPEX.

It will continue via the use of air interfaces that make better use of the spectrum and that don’t drain the battery, thereby enabling users to stay on-line all day. And then you need to have the kind of international roaming that we take for granted.

So, is it doable? Mobile operators are migrating their network cores to IP: high-speed packetised air interfaces will arrive in the 2010/11 timeframe: and the last part is a development known as IPX (IP eXchange). In a nutshell, this is a private IP interworking network that operators will use to exchange traffic. It won’t be accessible from the Internet, so it should be secure, and QoS will be managed using the DiffServ traffic class methodology.

TAKING ROAMING FOR GRANTED

The ability to roam is great: the cost isn’t. We therefore have solutions such as FMC (Fixed Mobile Convergence) that transfer cellular calls to and from WLANs in hot spots, homes and offices. But wouldn’t it be nice if we could stop all the high-tech ‘band-aid solutions’ and just get low-cost, high-quality telephony anywhere and at anytime. That’s what the emerging markets need and that is what IPX looks set to enable. So, say goodbye to FMC and hello to FMS (Fixed Mobile Substitution). We can therefore look forward to employing mobile services having fixed line quality at IP prices.

IT WAS A BUSINESS ISSUE

IPX isn’t rocket science. Fixed and mobile network operators as well as service providers simply connect to each other via the fat pipes of a “carrier’s carrier” using agreed specifications. Large operators may connect direct to each other, but since there are around 740 mobile operators around the world bilateral deals are clearly impractical. Instead operators will employ the services of a trusted ‘broker”, i.e. operators connect to the nearest broker.

Brokers aggregate the traffic and they connect to other brokers in order to create a global network. Thus, everybody has a virtual connection to everybody else. Brokers also handle the billing. Parties who meet their mutual obligations in the value chain receive a fair commercial return.

Setting up an operation of this size clearly takes time and it’s a very significant development, but it’s driven by the need to be competitive with those Internet-centric service providers. If they weren’t there it wouldn’t happen.

BROADBAND AIR INTERFACES

End-user data rates for Mobile WiMAX will probably vary between 2 and 12 Mbps. LTE is a newer technology that is in field trials and rates here should be 3 to 4 times higher. The former services look set to roll out in a 2009-10 time frame: the latter will come a couple of years later.

Marry these rates to the IPX service delivery model and you get a lot more than high-quality, low-cost telephony. Mobile multimedia services like real-time video and IPTV will be delivered at low-cost and they’ll have fixed-line quality.