TelstraSaturn sources say the company already has customers lined up for its planned mixed-media 1Gbit/s IP-based network, but likely large users appear more tentative.
A highly placed company staffer says TVNZ has expressed interest in becoming an early customer. Other unnamed customers or strong prospects are in medical imaging - transmission of X-rays and other diagnostic images - among hospitals and "one of the banks". A publisher has also expressed interest in using the network, the source says.
TVNZ technology chief Neil Andrews says, however, that no decision has been made yet on using the network. He puts it in the category of a new development that the company is watching, "just as we try to keep aware of other new developments in IT and telecommunications - but there are no specific plans for it”.
Paul Richards, a spokesman for publisher INL, tells a similar story.
Other possible prospective customers in these areas either give flat denials of firm plans, or did not immediately return calls.
The network, being constructed by Ericsson as prime contractor, is planned to be available in Auckland, Wellington and Christchurch by June.
TelstraSaturn will ensure quality of service (QoS) on the network by tagging packets with a "QoS parameter" and using application-specific integrated circuits (ASICS) to access that parameter without delay to the packet, says TelstraSaturn engineering spokesman Tony Baird. The service will provide 16 levels of service quality, with voice-over-IP and other delay-sensitive services like video at the top of the range, he says.
If the network becomes congested, lower-priority packets will be dropped.
IP is notorious for delay and dropping of packets, with consequent disruption to high-bandwidth communication. Work is going on to alleviate this problem with the new version 6 of IP (IPv6). But the current IPv4 already has a QoS field in the packet, says Baird. “The trouble is that it’s quite a way down the packet, and the [network equipment] has to drill down to find it.” This potentially creates its own delay problems.
The ASICS, supplied by subcontractor Extreme Networks, will get round this problem by finding and interpreting the QoS parameter at the speed of transmission, Baird says.
The network will take the form of a double ring, for 1Gbit/s of traffic flowing in each direction. A fibre break or equipment failure at any point will cause the signal to “loop back” around the other ring. This "healing", Baird says, will be possible within less than 200 milliseconds – or so Extreme has promised.
Although the network is designed primarily for business, it will not be limited to central business districts, Baird says. TelstraSaturn will, for example, be putting a gigabit link in to a South Auckland industrial estate. “All our greenfield network building will use this technology, and we will put the necessary equipment into the street cabinets of our existing networks where demand arises.”
Customers who need the 1Gbit/s speed will take it over fibre “all the way to their wall-plug,” says Baird, but several users with lower demands in the same building will be serviced by fibre to a device in the basement and Category 5 copper cable up the building from there.
The percentage of 1Gbit/s customers will be bound to increase from the already encouraging base of interest, he says – “people will be expecting 10 to 100Mbit/s to their desktops very soon.” As the network becomes inevitably more congested, TelstraSaturn will avail itself of higher-capacity fibre-transmission technologies such as dense wavelength division multiplexing (DWDM).