Ofcom's rules under the Communications Act 2003 require providers to take all necessary measures to ensure uninterrupted access to emergency organisations as part of any call or voice services offered. Providers must also take appropriate and proportionate measures to identify and reduce the risks of the availability, performance or functionality of their network or service being compromised, said the regulator.
Additionally, Ofcom said that providers are required to take appropriate and proportionate measures to prevent adverse effects from any such compromise. In the event there are negative effects, they should take steps to remedy or mitigate those effects, it said.
Providers are also required to inform Ofcom, as soon as reasonably practicable, of any security compromise that has a significant effect on the operation of a network or service.
Ofcom's investigation will seek to establish the facts surrounding the incident and examine whether there are reasonable grounds to believe that Vonage has failed to comply with its regulatory obligations.
Vonage had not responded to a request for comment at time of publication.