Carrier gateway set to support wireless network roaming

A new gateway may soon make it possible for mobile workers to roam among existing and emerging cellular data networks as well as public-access wireless LANs.

The carrier-based gateway being developed by Megisto Systems Inc. of Germantown, Md., identifies a mobile subscriber, assigns a mobile IP address, and then tracks the subscriber’s activities and net usage. The gateway uses this data, plus a set of interfaces to the carrier’s existing network billing and service systems, to associate specific services with each subscriber and create a single bill.

While this kind of subscriber data is widely used in cellular voice nets today, Megisto’s gateway appears to be the first product that extends this kind of provisioning to wireless data nets connecting to the Internet, including users accessing net services via a public wireless LAN (WLAN) in a convention centre, airport or coffee shop. Enterprise users could log on to corporate data using a WLAN service at a convention centre, and at another location, check their e-mail using a Code Division Multiple Access (CDMA) or Time Division Multiple Access cellular net, or in the future, a higher-bandwidth 3G net. All connections and services would appear on one bill.

In theory, the users could ignore any details of which radio technology was handling the connection. But that may take some time: Device makers will have to incorporate new code into their handsets, PDAs and portable computers to automatically detect spectrum changes. And the client devices themselves will have to include interface cards to each net, such as CDMA cellular nets and 802.11b WLANs.

ISPs and carriers building public access WLANs, sometimes called hotspots, have been forging billing arrangements so that each subscriber doesn’t have to set up a different account, with a different logon and possibly a different configuration, for each provider. But these billing deals don’t solve the problems created by the use of different wireless technologies, says Carol Politi, co-founder and vice-president of marketing for Megisto.

Megisto, founded in May 2000, is taking on a big project. In effect, it’s creating the hardware and software infrastructure that will let carriers and mobile operators use several wireless technologies to connect hundreds of thousands, even millions, of mobile subscribers to IP data services from the carriers, and from carrier partners.

The management team has technical and marketing experience with such companies as Ericsson’s IP Infrastructure Division, Bell Labs and Advanced Switching Communications. Robert Pavlak, vice-president of engineering formerly with Bell Labs, has been involved in developing GSM and 3G Universal Mobile Telecommunications System technology.

Investors such as Columbia Capital, Bessemer Venture Partners, and Lucent Venture Partners have shelled out about US$50 million in funding.

The first Megisto gateways will ship later this year.