Abstract: Control messages constructed in accordance with a first communications protocol for use in a communications network each include a first address identifier having a format defined by the first protocol. The control message is processed to derive a second address identifier having a format defined by a second communications protocol. The control message is re-formatted for transmission, in accordance with the second protocol, to a network system associated with the second address identifier.

Abstract: The invention provides a method, data processing system and software for generating address identifiers for use in a communications network. The method comprises the step of processing a first address identifier constructed in accordance with a first communications protocol; and the step of constructing a second address identifier, from said first identifier, in accordance with a second communications protocol. The first communications protocol may be protocol Simple Mail Transfer Protocol (SMTP) and the second communications Session Initiation Protocol (SIP). The invention enables messages to be sent to a SIP URL derived from an SMTP email URL. In the event that the SIP URL is invalid, or unregistered the SIP message is diverted from a SIP defined destination URL address identifier to a corresponding SMTP defined destination URL address identifier for the same user or end system.

Abstract: The invention provides a method, data processing system and software for generating address identifiers for use in a communications network. The method comprises the step of processing a first address identifier constructed in accordance with a first communications protocol; and the step of constructing a second address identifier, from said first identifier, in accordance with a second communications protocol. The first communications protocol may be protocol Simple Mail Transfer Protocol (SMTP) and the second communications Session Initiation Protocol (SIP). The invention enables messages to be sent to a SIP URL derived from an SMTP email URL. In the event that the SIP URL is invalid, or unregistered the SIP message is diverted from a SIP defined destination URL address identifier to a corresponding SMTP defined destination URL address identifier for the same user or end system.

Abstract: The invention provides a method, data processing system and software for processing control messages constructed in accordance with a first communications protocol for use in a communications network. Each control message includes a first address identifier having a format defined by the first protocol. The method comprises the step of processing said control message to derive a second address identifier from said first identifier, said second identifier having a format defined by a second communications protocol; and, the step of re-formatting said control message for transmission, in accordance with said second protocol, to a network system associated with said second address identifier. The first communications protocol may be Session Initiation Protocol (SIP) and the second communication protocol Simple Mail Transfer Protocol (SMTP).