A software patch intended to fix Telecom's ailing ISDN switches has failed, casting doubt on its ability to provide widespread ISDN service--and creating potentially serious problems for Xtra's new local dial-up service.
The NEC-designed switches in Telecom's exchanges have a bug which affects users of the Ascend ISDN product--a digital front end which handles large numbers of dial-in lines--including The Internet Group (Ihug) and Telecom's own Xtra service. Ascend depends on D-switching, which counts calls as they come in and switches over to a new block of 30 channels as each block fills up. But if two calls come in simultaneously, the NEC switches "lose count" and fail.
D-switching support is built in to Telecom's 0800 software, so the bug is not an issue for Xtra's 0800 access service. But the patch from NEC was delivered shortly before Xtra brought forward its announcement of price cuts for dial-in access--and failed shortly after the announcement.
This means Xtra may strike the same problems as Ihug, which is "seriously considering" legal action against Telecom, with spokesman Tim Wood claiming Telecom's inability to fix its ISDN provision meant his company was having to stop taking new customers. It could no longer use the workaround of making new connect scripts, with additional new dial-in numbers, available to customers.
"Busy signals were starting to return and we can't add any new lines until Telecom gets its act together," says Wood. "The basis of their network seems pretty shaky--especially compared to Telstra, who we've had some dealings with. Telecom can't offer us any ISDN provision whatsoever in Wellington, which has stopped us dead."