Optical/IP Networks

Seranoa Tackles Backhaul Bandwidth

Seranoa Networks Inc. today introduced a family of service edge concentrators that reduce the bandwidth required for carriers to backhaul T1 traffic over Sonet metro access networks.

The basic sales pitch is that Seranoa believes its equipment can slash carriers’ capital expenditures by 70 percent and operating expenditures by 50 percent, by eliminating the backhaul of unused T1 bandwidth (See Secretive Seranoa Scores $15.75M.)

This is a very focused product strategy, and it's one that might work by allowing the myriad service providers selling to the enterprise networking market to lower their costs.

“It’s a real pragmatic approach to saving both product costs and, more importantly, metro bandwidth on the Sonet and SDH rings,” says Michael Howard, an analyst at Infonetics Research Inc.

Here's why: With all due respect to much-hyped metro Ethernet services, most small and medium businesses still use services like Internet access, IP virtual private networks, and local and long-distance voice via a T1 connection. The service providers, such as AT&T Corp. (NYSE: T) and Allegiance Telecom Inc., typically concentrate subscribers’ T1 connections in a central office (CO) owned by an incumbent local exchange carrier (ILEC) and backhaul the T1 traffic to their points of presence (POPs) over Sonet metro access networks.

The trouble is, most subscribers use only half the bandwidth on their T1s. Yet all of the T1 bandwidth, including the unused portion, gets backhauled to the service provider’s POP over another carrier’s Sonet network, and the service provider has no way of grooming the traffic or multiplexing IP packets at the CO to save bandwidth.

Seranoa is addressing these problems with its IPeX 200 and IPeX 400 boxes. “Our focus allows carriers to provide dramatic savings, particularly in backhaul bandwidth and operational cost savings,” says Sally Baman, senior VP of marketing at Seranoa.

Light Reading readers will recognize the IPeX 200 as a renamed version of the WANport, which Seranoa introduced last year (see Seranoa Surfaces and Seranoa Customers Pipe Up). The WANport sits in front of an edge router in a POP and aggregates T1 circuits into a Gigabit Ethernet port on the edge router. The approach costs about one third the price of feeding T1 circuits directly into a channelized T3 port on an edge router from Cisco Systems Inc. (Nasdaq: CSCO) or Juniper Networks Inc. (Nasdaq: JNPR), according to Seranoa.

The IPeX200 comes with an incremental software upgrade that improves the WANport’s command line interface, among other things. The IPeX400 differs more noticeably by adding grooming capabilities, the ability to accept clocking information for TDM traffic, and an on-board Ethernet switch. Designed for deployment at the CO, the IPeX400 grooms T1 traffic before it is backhauled via Sonet to the POP, cutting backhaul bandwidth consumption in half and increasing subscriber capacity by up to ten times, Seranoa says.

Infonetics' Howard points out that such an arrangement prevents the un-groomed information from being backhauled inefficiently over the rings and saves on costly edge router ports and DACS equipment at the POP.

"Rather than allocating bandwidth for each customer on an SDH or Sonet ring, you can do the grooming immediately," says Howard.

A service provider must decide whether the cost of adding another box to its network is worth the savings. The IPeX products list for $5,000 per channelized T3 port. Seranoa says channelized T3 ports on edge routers cost about $16,000 apiece and concentrate 28 T1 lines each.

North Atlantic Internet Inc. (NAII), an ISP in Boston, has been using the WANport since last year. “We’ve replaced a huge amount of Cisco gear with it,” says Burke Anderson, the company’s president and CEO. NAII plans to deploy the IPeX400 in its collocation facilities in the next two to four months.

“Now, if you have four T3s worth of T1s at the CO and maybe they’re only using two T3s' worth, why would you want to buy [the excess] for backhaul?” says Anderson, who hopes to eliminate the problem with the IPeX400.

Cisco had no comment on the NAII situation or Seranoa's claims. "Typically, Cisco doesn’t comment on competitive announcements,” says Robert Barlow, a Cisco spokesman.

— Justin Hibbard, Senior Editor, Light Reading

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