Zen Internet, a reseller of BT Wholesale's ADSL broadband service, has stopped processing new orders while it waits for an upgrade to its central pipe.
The ISP claimed that more of its existing 34Mbps pipe was being used up in routing and addressing traffic (overhead), some 20 per cent, than it been warned to expect by BT Wholesale.
"The overhead used to carry this transfer out is quoted at around 10 per cent by BT, meaning that in reality the 'pipe' is capable of transferring 30.6Mbps of IP traffic," said Ian Buckley, marketing manager at Zen Internet.
"We have discovered this overhead to be higher - in the region of 20 per cent - resulting in an earlier than expected need for upgrading.
"Bandwidth of the central pipe is not yet being saturated and is running under recommended levels, but the addition of further customers would cause Zen's ADSL service provision to deteriorate."
Zen said it expected to install the extra bandwidth by 12 December.
It is still taking orders, but will not process them until after that date.
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