A new report published by the Commerce Commission says Telecom’s claim that unconstrained broadband will lead to a loss of service for tens of thousands of customers is bogus.
It says it is based on incorrect technical assumptions.
The report comes hard on the heels of Telecom’s network management company, Alcatel, stating that unless the last-mile copper network is in excellent repair, only customers living very close to exchanges will get fast broadband.
Alcatel echoes Telecom’s claim that unconstrained broadband will lead to a large number of customers losing service.
However, the report, which is on local-loop spectrum management and was prepared by Paul Brooks, of Australian consultancy Layer Ten, says Telecom’s claim that unconstrained broadband will diminish service reach is wrong.
Telecom claims that unconstrained DSL increases interference and says bit-rates have to be decreased so as to reduce transmission power.
However, Brooks says the notion of bit-rate limiting as a form of transmission power control has little merit. More importantly, it confers absolutely no benefit when it comes to improving the reach of services on long lines.
Instead, Brooks says, any reduction in data rates is caused by the number of devices operating on the same line. This effect is actually more of a problem on shorter reaches of line rather than longer ones when it comes to ADSL, he says.
At the moment, Telecom does not have a spectrum management plan for its DSL network, which was deployed in 1999.
The term “spectrum management” is something of a misnomer, says Brooks. He adds that the goal of any plan should be to minimise the effects of interference (as per international norms).
Brooks says it’s surprising a carrier of Telecom’s size hasn’t referenced any previous engineering standards or guides.
A prudent network operator would have installed a spectrum management scheme before the introduction of ADSL. This would ensure important business services were not disrupted during a future widespread consumer broadband roll-out.
Brooks doesn’t see any significant value in putting a plan into place now, as first-generation ADSL has already been deployed. Moving to next-generation ADSL2 would take care of many outstanding issues, says Brooks. The newer equipment has much improved transmission power-control and error-correction compared with the first generation technology still being used in New Zealand.
ADSL2, and the adjunct ADSL2+ standards, were ratified in 2002 and 2003, respectively, and have been rolled out around the world. In contrast, Telecom says it plans to focus on unconstrained bit-stream this year and delay the introduction of ADSL2+ until the second half of 2007 — this is despite Telecom chief executive Theresa Gattung promising the latter would come on-line in June this year.
Telecom fought unconstrained DSL tooth and nail during the consultative process that preceded the Commerce Commission’s determination on TelstraClear’s application.
One of the arguments Telecom used was that customers in rural and provincial areas would be left without a broadband service should unconstrained broadband be allowed.
However, the telco could provide such a service to these remote customers through Reach Extended ADSL2, says Brooks. This technology sacrifices some performance but can go a great deal further than standard broadband, he says.
A key reason why Telecom wants to resist unconstrained broadband is identified in the report: symmetric DSL. This technology, which Telecom uses for its high-value Frame-Relay service, as well as similar services, is adversely affected when it comes to reach by increased ADSL deployment.
Despite protesting about the detrimental effects unconstrained DSL has on customer connections, Telecom has already started marketing unconstrained DSL for its Xtra ISP business.
In addition, it is in negotiation with its wholesale partners over access to a similar service which could be up-and-running by September or October.