Method and system for enhanced call completion in telecommunications mobility applications

• US 5,590,175 A
• Filed: 05/17/1995
• Issued: 12/31/1996
• Est. Priority Date: 05/17/1995
• Status: Expired due to Term

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: MCI Communications Corporation (Verizon Communications Inc.)
• Inventors: Donovan, Steven R., Gallant, John K.
• Primary Examiner(s): Kuntz, Curtis
• Assistant Examiner(s): OEHLING, GEORGE J
• Application Number:
  US08/443,185
• Time in Patent Office: 594 Days
• Field of Search: 379/58, 379/59, 379/60, 455/33.1, 455/33.2, 455/56.1
• US Class Current: 455/433
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]
• CPC Class Codes: H04W 8/18 Processing of user or subscriber data, e.g. subscribed services, user preferences or user profiles; Transfer of user or subscriber data

Abstract

A call directed to a mobile telephone station from a public switch telephone network is received in a mobile services switching center of a mobile telephone network. An attempt is made to locate the profile of the mobile telephone station in a visitor location register. If the mobile telephone profile is not found in the visitor location register, a query message is sent to a home location register requesting routing information for the call. The profile has an HLR query flag for indicating whether the home location register should be queried. If the profile of the mobile telephone station is found in the visitor location register, the status of the HLR query flag is checked. If the HLR query flag is set to yes, a query message is sent to a home location register requesting routing information for the call. If the HLR query flag is set to no, the call to the mobile telephone station is completed using the profile in the visitor location register. In all other cases, a query message requesting routing information has been sent to the home location register, so the call to the mobile telephone station is completed using the routing information received from the home location register.

Claims

1. A method of directing calls from a public switch telephone network to a mobile station within a mobile telephone network, the mobile telephone network including a plurality of mobile telephone stations, a plurality of base stations for communicating with the mobile telephone stations, a plurality of mobile services switching centers for routing calls between base stations and between base stations and the public switch telephone network, a plurality of visitor location registers for storing data relating to visiting mobile telephone stations, and at least one home location register for storing all management data relating to all mobile telephone stations in the mobile telephone network, the method comprising the steps of:

receiving a call directed to a mobile telephone station from a public switch telephone network in a mobile services switching center;

attempting to locate a profile of the mobile telephone station in a visitor location register, the profile having an HLR query flag for indicating whether the home location register should be queried;

checking a status of the HLR query flag, if the profile of the mobile telephone station is located in the visitor location register;

sending a query message to a home location register requesting routing information for the call, if the HLR query flag is set to yes;

completing the call to the mobile telephone station using the profile in the visitor location register, if the HLR query flag is set to no;

sending a query message to the home location register requesting routing information for the call, if the mobile telephone profile is not found in the visitor location register; and

completing the call to the mobile telephone station using the routing information received from the home location register, if a query message requesting routing information has been sent to the home location register.

2. The method of claim 1, further comprising the step of:

receiving routing information from the home location register.

3. A system for directing calls from a public switch telephone network to a mobile station within a mobile telephone network, the mobile telephone network including a plurality of mobile telephone stations, a plurality of base stations for communicating with the mobile telephone stations, a plurality of mobile services switching centers for routing calls between base stations and between base stations and a public switch telephone network, a plurality of visitor location registers for storing data relating to visiting mobile telephone stations, and at least one home location register for storing all management data relating to all mobile telephone stations in the mobile telephone network, the apparatus comprising:

means, coupled to a public switch telephone network, for receiving a call directed to a mobile telephone station from the public switch telephone network;

means, coupled to the call receiving means and to a visitor location register, for attempting to locate a profile of the mobile telephone station in the visitor location register, the profile having an HLR query flag for indicating whether the home location register should be queried;

means, coupled to the profile locating means, for checking a status of the HLR query flag, if the profile of the mobile telephone station is located in the visitor location register;

means, coupled to the status checking means and to a home location register, for sending a first query message to a home location register requesting routing information for the call, if the HLR query flag is set to yes;

means, coupled to the status checking means, for completing the call to the mobile telephone station using the profile in the visitor location register, if the HLR query flag is set to no;

means, coupled to the profile locating means and to the home location register, for sending a second query message to the home location register requesting routing information for the call, if the mobile telephone profile is not found in the visitor location register; and

means, coupled to the profile locating means, the status checking means and the home location register, for completing the call to the mobile telephone station using the routing information received from the home location register, if a first or second query message requesting routing information has been sent to the home location register.

4. The system of claim 3 further comprising:

means, coupled to the home location register and to the call completing means, for receiving routing information from the home location register.