APPARATUS AND METHODS OF SIP VIA FIELD COMPRESSION IN SESSION INITIATION PROTOCOL SIGNALING FOR 3G WIRELESS NETWORKS

摘要

Session initiation protocol "SIP" signaling for 3G wireless networks is provided by using compression in the VIA field to reduce the signaling overhead in SIP messages. Methods of compression include eliminating redundant address information found in each intermediate address along the path traveled by the message and tokenizing certain elements of the header and using the tokens in the VIA header in place of the raw strings. A network device receives (250) an SIP message and examines the VIA field in the header information of the SIP message to identify (260) the domain from which the SIP message was sent. If the domain is not the same (270) as the current domain, then the network device appends (280) the current domain in the VIA field and sends the message along its path to the destination node. If the domain is the same (270) as the current domain, then the network device compresses (290) the domain information and appends (300) the compressed domain information in the VIA field and sends the message along its path to the destination node.