VoIP phone system - stable and additional work planned


[22 May 2015]

Update 22 May: Over the last week considerable work has taken place to investigate the cause of the problems affecting the University's VoIP service. In addition, work has been done to improve the resilience of the service. Thanks to that work the service has now been stable for the last four days and we expect it to remain that way.

The cause of the original problems were cards in one of the University's older telephone exchanges, which provide the interface to the VoIP service. The VoIP service is dependent on connecting to the older telephone exchanges to make calls to the rest of the University and the rest of the world. Interface cards within one of these exchanges repeatedly failed, even when the hardware was replaced and the software changed.

Our supplier has still been unable to identify the root cause of the original problem and investigations are continuing into this. However, the service is now being delivered via new interfaces in alternative telephone exchanges, and this is all working as expected. The original faulty interfaces have been isolated to ensure they do not cause problems for telephone users.

We are currently at slightly greater risk than normal, due to lack of some backup routes. However, we had already planned to implement new routes by the end of June. Once this work is complete this will increase resilience, increase capacity, and remove the dependence on the older exchanges.

We would like to apologise to all the VoIP users affected and reassure you that we now believe the service is stable and will soon be robust.

Update 4.45pm, 13 May: There was a break in the VoIP service for approximately 5minutes around 4.30pm. Before that the VoIP service had been generally stable from 9.30am on 12th until 4.30pm on the 13th. Investigations into the cause of the problems affecting the VoIP phone service are continuing, and we are also continuing to work on alternative solutions for those affected by the problem.

Update midday, 13 May: Investigations into the cause of the problems affecting the VoIP phone service are continuing. We are assisting the supplier, Siemens Unify, to investigate all aspects of the process to identify the problem and implement a final fix. We are also continuing to identify alternative solutions for those affected by the problem.

Update 10.20am, 13 May: The VOIP service is currently functioning and has been functioning since 9.40am, following a repeat of problems which began at 8.30am. People on the VOIP service can make and receive calls. However, the service should be considered at risk until further work currently underway is completed to provide extra resilience for the service.

Since Friday 8th May we have experienced intermittent problems with the VoIP phone service.

During these periods VoIP phone users have been unable to make external or internal calls or receive calls from outside the VoIP phone system. Those using VoIP phones are able to call 999 and 112 on the phones in an emergency.

Phones on the VoIP system can be identified by the initial numbers '41' at the start of the internal number eg. 0117 39 41XXX

Some parts of the University are on the VoIP system and callers may have experienced issues with contacting staff in those teams. This includes teams or staff in:

  • Life Sciences Building
  • Langford
  • Campaigns & Alumni
  • Admissions 
  • IT Services

Most phone users in the University are not on this system and were not affected.

IT Services apologise for the inconvenience this is causing.