Mobile and fixed-line telecommunications networks experienced severe congestion on Thursday morning as Londoners attempted to contact friends and relatives in the wake of the bomb blasts.
BT, the UK’s largest fixed-line operator, and Vodafone, the country’s largest mobile operator, were forced to issue pleas to their customers to avoid unnecessary phone calls and keep their conversations brief.
Vodafone said the levels of calls on its network had been “unprecedented”. However, operators said none of the networks actually crashed under the weight of calls.
“The network was undamaged,” said Ben Padovan, a spokesperson from of Vodafone. “There was a phenomenal surge in calls and considerable congestion. It might have taken people three or four tries to get a call through but the network did not go down.”
BT said some callers might have experienced difficulties in getting through in the morning, but overall its system coped well. C and call levels had returned to normal by the end of the afternoon, BT said.
Difficulties in getting through on mobiles and land lines were heightened on Thursday because of the national emergency procedures telecoms companies are required to put in place when an event such as a bomb attack takes place.
Operators must give priority to emergency calls, and make sure that interconnection between different mobile and fixed-line operators works seamlessly.
However, the Mobile operators denied rumours that they had been ordered to shut down networks by the government because of fears mobile phones might be being used to detonate explosions.
“The first thing we do in these situations is to contact the Home Office and and offer our help, but the government hasn’t requested it,” said Stuart Jackson, spokesman from of Orange.
Operators said there was little they could do to increase capacity on their networks when they were hit by a sudden surge of calls.
“When you know there are going to be a lot of people in an area making calls - such as at Glastonbury - you can put in temporary base stations to accommodate it, but when it comes out of the blue, it is hard to do that,” said Mr Padovan.
Engineers were able to tweak mobile phone cells slightly to increase their capacity, but not by enough to accommodate the volume of extra calls that were experienced on Thursday.