Alcatel boosts DSL bandwidth

Alcatel’s recently unveiled 7301 DSL access multiplexer is designed to support high-end business-class DSL services and larger concentrations of residential users, making it easier for Alcatel carrier customers, such as Bell Canada and Telus, to expand their DSL footprints.

The key features of the 7301 Advanced Services Access Manager (ASAM) are a larger backplane and improved quality of service features, said Jay Fausch, senior director of marketing for Alcatel’s fixed networking division.

While the 7301’s predecessor, the 7300 ASAM, could support only 155Mbps of throughput per slot, the 7301 offers up to 1.5Gbps per slot and 170Gbps of overall throughput for the chassis.

“That’s more than enough throughput to handle any application you can conjure up, including multiple channels of broadcast-quality video to thousands of users,” Fausch said.

Alcatel estimates the 7301 can support up to 10,000 simultaneous DSL users through a combination of native ports and remote terminal connections.

The 7300 has traditionally been deployed in telco central offices, but Alcatel officials believe many carriers will deploy the 7301 in remote terminals. With its larger backplane, the 7301 can aggregate other remote terminal connections, saving carriers money on their backhaul line costs.

Instead of requiring a long backhaul run from each remote terminal to a central office, carriers could use shorter backhaul connections back to a 7301 in a remote terminal and then use one large backhaul link from the 7301 back to a central office for a more efficient use of backhaul bandwidth.

The 7301 also makes it easier for carriers to offer quality-of-service guarantees, Fausch said. With the 7300, carriers wishing to offer guaranteed service levels would need to commit a dedicated virtual circuit to each DSL line. With the 7301, carriers can take customers on separate connections, groom the traffic together and combine multiple virtual circuits into one, more economical, virtual path.

Connections out to remote terminals could be as small as a DS-1 or as large as an OC-12 or gigabit Ethernet interface. Backhaul connections to a central office can also range from a DS-1 to OC-12 or Gigabit Ethernet.

Alcatel 7300 customers can upgrade to the 7301 by adding a new line card per shelf and installing new software. Fausch said such an upgrade could be performed within a regular telco maintenance cycle.

The 7301 should appeal to Canadian DSL carriers who are trying to keep up with DSL demand. The country’s two largest DSL providers, Bell Canada and Telus, are Alcatel customers.

“In terms of DSL growth we don’t see an end,” said Iain Grant, managing director of telecom consultancy the Seaboard Group in Montreal. “We’re still seeing DSL rollouts and pushes by Bell, by Telus and even by Sprint now.”

There are currently about 3.5 million high-speed Internet connections in Canada and approximately half of those are DSL, according to Seaboard. DSL has fared better in the Canadian market against cable than it has in the U.S. market, because Canadian carriers have been more aggressive in marketing DSL than their U.S. counterparts, said Brian Sharwood, a principal with Seaboard.

The 7301 is in some carrier labs now and deployments could begin in the second half of this year, Fausch said.

At the high end, upgrading from a 7300 to a 7301 would cost about 25 per cent of the original cost of the 7300.