Patent ID: 8965969
Filing Date: 2015-02-24
Classification: H04L

Abstract:
1. A method of facilitating communication between users of a SIP-based network comprising a first peer-to-peer network and SIP users external to the SIP-based network, where each user of the SIP-based network possesses a SIP URI comprising a first host name part belonging to the network and a user name part, and said external users have access to a second peer-to-peer network to resolve SIP URIs into contact IP addresses and each external user possesses a SIP URI comprising a second host name part, the method comprising: publishing into said second peer-to-peer network a mapping between an identifier of a gateway to said SIP-based network and an IP address of the gateway, said identifier corresponding to or being derivable from said first host name part; upon receipt of a first query at the gateway in respect of a URI associated with one of said users of said SIP-based network, resolving that URI into a contact IP address by performing a look-up in said first peer-to-peer network, and also in response to receipt of the first query at the gateway returning the contact IP address to a node from which the first query originated; publishing into said first peer-to-peer network a mapping between an identifier of said gateway and an IP address of the gateway, said identifier corresponding to or being derivable from said second host name part; and upon receipt of a second query at the gateway in respect of a URI associated with one of said users of said second peer-to-peer network, resolving that URI into a contact IP address by performing a look-up in said second peer-to-peer network, and returning the contact IP address to a node from which the second query originated.