Efficient address caching for packet telephony services

An apparatus comprising:

• a server which is configured to receive a subscriber request from a plurality of clients connected to the server via a packet switched network data link to retrieve URI information associated with a telephone number, the URI information comprising a packet network address and one or more of the following additional information:
• fraud scoring, number portability information, advertising IDs, current geo-location, financial services, application or service provider and security information;
• and
• a first database which is configured to store records associating telephone numbers with respective URIs,
• wherein the server is configured, in response to the subscriber request, to query a first database to check if the first database holds a record comprising URI information associated with the telephone number;
• if the first database holds a record for the telephone number including one or both of the packet network address and additional information, the server obtaining and storing the record;
• and
• if the record holds the packet network address and one or more of the additional information, the server initiating a communication based on the packet network address and the one or more additional information;
• and
• if the record does not hold the packet network address, the first database providing the additional information and notifying the server that no packet network address was found;
• if the first database does not hold a record for the telephone number or if the first database does not hold a record for the telephone number including both of the packet network address and additional information, the server sending a request to one or more subsequent database to check if the one or more subsequent database holds a record for the telephone number;
• if the one or more subsequent database holds a record for the telephone number, the server obtaining and storing the record;
• and
• if the record holds the packet network address and one or more of the additional information, the server initiating a communication based on the packet network address and the one or more further information obtained from the one or more databases;
• and
• if the record does not hold the packet network address, the one or more subsequent database providing any of the further information and notifying the server that no packet network address was found;
• and
• if none of the databases holds a record for the telephone number, storing a negative response that no record associated with the telephone number was found.

A system comprising:

• a server which is configured to receive a subscriber request from a plurality of clients connected to the server via a packet switched network data link to retrieve URI information associated with a telephone number, the URI information comprising a packet network address and one or more of the following additional information:
• fraud scoring, number portability information, advertising IDs, current geo-location, financial services, application or service provider and security information;
• and
• a first database which is configured to store records associating telephone numbers with respective URIs,
• one or more subsequent database, the or each of which is configured to store records associating telephone numbers with respective URIs,
• wherein the server is configured, in response to the subscriber request, to query the first database to check if the first database holds a record comprising URI information associated with the telephone number;
• if the first database holds a record for the telephone number including one or both of the packet network address and additional information, the server obtaining and storing the record;
• and
• if the record holds the packet network address and one or more of the additional information, the server initiating a communication based on the packet network address and the one or more additional information;
• and
• if the record does not hold the packet network address, the first database providing the additional information and notifying the server that no packet network address was found;
• if the first database does not hold a record for the telephone number or if the first database does not hold a record for the telephone number including both of the packet network address and additional information, the server sending a request to the one or more subsequent database to check if the one or more subsequent database holds a record for the telephone number;
• if the one or more subsequent database holds a record for the telephone number, the server obtaining and storing the record;
• and
• if the record holds the packet network address and one or more of the additional information, the server initiating a communication based on the packet network address and the one or more further information obtained from the one or more databases;
• and
• if the record does not hold the packet network address, the one or more subsequent database providing any of the further information and notifying the server that no packet network address was found;
• and
• if none of the databases holds a record for the telephone number, storing a negative response that no record associated with the telephone number was found.