Patent ID: 6738471
Filing Date: 2004-05-18
Classification: H04Q

Abstract:
Method for ensuring a PSTN protocol restart procedure as defined by a V5 standard after a failure of a first data link carrying PSTN protocol signalling messages, the method comprising:observing a first time-out for starting a restart procedure; if the first time-out has tripped, starting the restart procedure by sending a start message using a Control protocol signalling message consistent with a V5 standard; after a first data link carrying a PSTN protocol has been restored to working order, performing a check to establish whether a second data link intended to carry the Control protocol signalling messages is in order; repeating the check until the second data link intended to carry the Control protocol signalling messages is in order; and sending, when the second data link is in order, a message for starting the PSTN protocol restart procedure in the Control protocol.