The significance of PTAT-1 is that it broke the international telecommunication monopoly held by AT&T Corporation and British Telecom (BT) for telecommunications between the US and UK.
The UK to US section of the cable was shut down just after 02:00 hours on 8 February 2004, as it was no longer considered financially viable by Cable & Wireless. Competitors to the cable had dropped their prices drastically after they re-emerged from Chapter 11 Bankruptcy with little or no debts to service, something C&W was unable to compete with.[citation needed]
This cable provided intelligent repeaters that counted bit errors which were reported in response to interrogation from a base station. It contained three fibre pairs which were used to provide two active channels. Each repeater included a base station-controlled cross-over data switch to swap traffic through a choice of two fibre pairs, the switch connections in successive repeaters enabled any desired connection to be made and provide a diversity path when required.