# US 6,285,880 B1 · Intersystem message indicator specifying MIN or IMSI usage > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 6,285,880 B1 - Document ID: US6285880B1 - Status: Granted - Kind: B1 - Application number: 09/312,551 - Filed: 1999-05-14 - Granted: 2001-09-04 - Earliest claimed: 1999-05-14 - Assignees: Telefonaktiebolaget L M Ericsson (publ) - Inventors: Michel Gagnon; Uzma Abbas; Michel Houde - Web page: https://patentgrep.com/patent/US6285880B1 ## CPC - H04W 8/26: Network addressing or numbering for mobility support - H04W 36/0066: {of control information between different types of networks in order to establish a new radio link in the target network} - H04W 92/24: between backbone network devices - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A system and method for conveying data in an inter-exchange message, said data identifying a selected one of a plurality of mobile station identifiers to be used in connection with a particular mobile station. The mobile station selects said mobile station identifier prior to registering with a first mobile switching center. Subsequently, the mobile station moves into an area served by a second mobile switching center. An inter-exchange message containing information about the mobile station is then sent from the first mobile switching center to the second mobile switching center. The information includes the plurality of mobile station identifiers and an indication of which one of the identifiers has been selected for use by the mobile station. The selected identifier can then be extracted from the inter-exchange message and used by the second mobile switching center for paging the mobile station, for compiling statistics relating to the mobile station, or for other purposes in implementing the mobile telecommunications system. ## Claims ### Claim 1 A method for identifying which one of a plurality of mobile station identifiers is to be used in connection with a specified mobile station in a multi-exchange mobile telecommunications network, comprising the steps of: registering the mobile station in a first exchange; sending an inter-exchange signaling message associated with the mobile station from the first exchange to a second exchange, said inter-exchange signaling message including the plurality of mobile station identifiers and an indication of which one of the plurality of mobile station identifiers is to be used in connection with the mobile station; and selecting at the second exchange the particular one of the plurality of mobile station identifiers for use by the second exchange in connection with the mobile station, said selection made in accordance with the indication included in the inter-exchange signaling message. ### Claim 2 (depends on 1) The method of claim 1, wherein the step of registering includes the step of sending said particular mobile station identifier from the mobile station to the first exchange. ### Claim 3 (depends on 2) The method of claim 2, further comprising the step of storing said particular mobile station identifier in the first exchange. ### Claim 4 (depends on 1) The method of claim 1, wherein the inter-exchange signaling message associated with the mobile station comprises an inter-exchange page message. ### Claim 5 (depends on 4) The method of claim 4, further comprising the step of sending the inter-exchange page message to the second exchange in response to a determination that the mobile station has not responded to a page request issued by the first exchange. ### Claim 6 (depends on 1) The method of claim 1, wherein the inter-exchange signaling message associated with the mobile station comprises a handoff message. ### Claim 7 (depends on 1) The method of claim 1, further comprising the step of storing said particular mobile station identifier in the second exchange. ### Claim 8 (depends on 7) The method of claim 7, further comprising the step of collecting radio statistics at the second exchange using said particular mobile station identifier. ### Claim 9 (depends on 1) The method of claim 1, wherein the plurality of mobile station identifiers includes a Mobile Identification Number (MIN). ### Claim 10 (depends on 1) The method of claim 1, wherein the plurality of mobile station identifiers includes an International Mobile Station Identifier (IMSI). ### Claim 11 A mobile telecommunications system, comprising: a first mobile switching center storing an indication of a particular one of a plurality of identifiers associated with a registered mobile station, said particular identifier to be used in connection with the mobile station, wherein the first mobile switching center operates to send an inter-exchange message containing said plurality of identifiers and containing said indication; and a second mobile switching center receiving said inter-exchange message and retrieving said indication to determine which one of the plurality of identifiers to use in connection with the mobile station. ### Claim 12 (depends on 11) The mobile telecommunications system of claim 11, further comprising a visitor location register associated with the first mobile switching center for storing said indication. ### Claim 13 (depends on 11) The mobile telecommunications system of claim 11, further comprising a visitor location register associated with the second mobile switching center for storing said indication. ### Claim 14 (depends on 11) The mobile telecommunications system of claim 11 wherein the plurality of identifiers include a Mobile Identification Number (MIN) and an International Mobile Station Identifier (IMSI). ### Claim 15 (depends on 11) The mobile telecommunications system of claim 11 wherein the inter-exchange message comprises a page request. ### Claim 16 (depends on 11) The mobile telecommunications system of claim 11 wherein the inter-exchange message comprises a handoff request. ### Claim 17 A method for identifying a selected one of a plurality of mobile station identifiers to be used in connection with an inter-system page, comprising the steps of: registering a mobile station in a first mobile telecommunications exchange using said selected identifier; sending an inter-system page message from the first exchange to a second exchange, wherein said inter-system page message includes said plurality of mobile station identifiers and an indication of the selected identifier; and using the selected identifier at the second exchange to page the mobile station. ### Claim 18 (depends on 17) The method of claim 17 further comprising the step of receiving at said first exchange an incoming call directed to said mobile station, wherein the step of sending an inter-system page is responsive to said incoming call. ### Claim 19 (depends on 17) The method of claim 17 wherein the step of using the selected identifier to page the mobile station comprises the step of calculating an appropriate control channel for paging the mobile station using the selected identifier. ### Claim 20 A method for identifying a selected one of a plurality of mobile station identifiers to be used for a particular mobile station, comprising the steps of: determining that an inter-exchange handoff from a first exchange to a second exchange for the particular mobile station is necessary; sending a handoff request from the first exchange to the second exchange, said handoff request including said plurality of mobile station identifiers and an indication of the selected identifier; and storing the selected identifier at the second exchange for use in connection with the mobile station. ### Claim 21 (depends on 20) The method of claim 20 further comprising the step of using the selected identifier for compiling statistics relating to the particular mobile station.