Unisphere unites ATM and IP in one box

Looking to smooth service providers’ paths toward offering advanced services based on IP (Internet Protocol), Unisphere Networks Inc. on Monday announced a new series of routing switches for the edge of service-provider networks.

The MRX Multi-Service Edge Router combines native IP routing and ATM (Asynchronous Transfer Mode) switching and allows service providers to offer either type of service on any port or any individual circuit on a port, according to Bill Glynn, senior product line manager for Unisphere’s IP routing group.

Many incumbent service providers provide voice and data services using ATM, which can offer a guaranteed quality of service (QoS) for delay-sensitive traffic. Some are now migrating to IP, which promises to let them eventually offer sophisticated services such as voice calls, multimedia and videoconferencing over a single network. The migration is intended to simplify networks, meet growing bandwidth demands and lower costs, which could be passed on to customers.

With the MRX, carriers will be able to continue offering ATM services to some customers, with full support for the classes of service built in to ATM. At the same time, the carriers can shift other customers on to new IP services one circuit at a time. Using standard IP mechanisms such as MPLS (Multiprotocol Label Switching) and DiffServ (Differentiated Services), plus proprietary capabilities for treatment of traffic within the Unisphere switch, the MRX platform lets carriers keep giving the same kind of treatment to special traffic after the migration to IP, Glynn said. For example, the MRX never puts packets of voice traffic in queues to wait behind other traffic, he said.

Corporations are demanding reliable high-speed data connections, such as 155M bps (bit-per-second) OC-3 links, and in some cases the capability to do videoconferencing, said Christin Flynn, an analyst at Yankee Group Inc., in Boston. Many incumbent carriers have used ATM to provide those services, but they hope eventually to move to a single, converged network. However, swapping ATM switches for IP routers one box at a time is highly disruptive, she said.

“To truly migrate your Layer 2 (switched) networks to an IP-based core … you have to be able to do native ATM,” Flynn said. “You may want to move some of their traffic over to the IP core, but not all of it,” she added.

It remains to be seen whether Unisphere’s advanced functions will let carriers control service quality as well as they do with ATM, but the company is looking in the right direction, she said.

“Service providers are looking for something a little more deterministic in their IP networks,” Flynn said.

Many incumbent carriers are reaching the limits of capacity on their metropolitan ATM networks, which are based on aging ATM switches paired with traditional IP routers, said Tracey Vanik, an analyst at RHK Inc., in South San Francisco, Calif. In addition to providing ATM services to corporations, those networks may aggregate consumer broadband traffic from DSLAMs (digital subscriber line access multiplexers). The MRX gives them a chance to expand that capacity and also move from multiple boxes to one device, thus freeing up space in their facilities at the same time, Vanik said.

An MRX chassis can provide from 40Gbps to 320Gbps of total capacity depending on the number and type of modules deployed in it. Carriers can set up a wide range of optical interfaces, ranging from OC-3 to OC-48 (2.5Gbps) as well as Gigabit Ethernet. The MRX is available now. One chassis, with software, costs US$115,000. Pricing of interface modules varies depending on configuration, according to Unisphere spokeswoman Susan Ursch.

Unisphere, an affiliate of Siemens AG, is in Westford, Mass., and can be reached at http://www.unispherenetworks.com.