EP0544464A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus and method for maintaining stable virtual circuit data connections in cellular mobile telecommunications
Assignee: AT&T Inc
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Filing: 1992-11-19
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Granted: —
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Expires: 2012-11-19
Abstract
Abstract This invention relates to apparatus and methods for providing cellular mobile telecommunication service in accordance with the requirements of the Global Systems for Mobile Communications (GSM) standard. A modular switching system is provided which performs the functions of the mobile switching center (210) plus those of a home location register (212), authentication center (216), visitor location register (214), and equipment identity register (218). The latter functions are advantageously spread among the modules of the switching system, thus avoiding the getting started cost of expensive dedicated data bases. A wireless global switching module advantageously switches mobile communications control messages among the modules of the system and between the modules and the base station systems (204), and terminates signaling links between the mobile switching center and the base station systems.
Inventors
- 👤 Robert Byerly Beeson, Jr.
- 👤 Patrick Ernest Helmers
- 👤 Michael Vincent Stein
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 03:19
CPC Classifications
H; H04; H04W; H04W8/00; H04W8/18; H04W76/00; H04W76/20; H04W8/20; H04W92/00; H04W92/04; H04W92/14; H04W92/16; H04W92/24
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
90 words
A method of maintaining stable virtual circuit connections, each connection controlled by one serving protocol handler (PH) of a group of PHs, comprising: whenever a virtual circuit connection reaches a stable state, storing state information for said connection in a predetermined adjacent PH; in the event of failure of said serving PH, serving stable connections of said failed serving PH in said predetermined adjacent PH; and serving new connections destined for service by said failed serving PH in a spare PH which takes the role of said failed serving PH.
Claim 2
Dependent Claim
29 words
The method of claim 1 wherein a PH assigns a reference number, comprising a subfield, called a logical PH number, identifying that PH, to each new virtual circuit connection.
Claim 3
Dependent Claim
43 words
The method of claim 2 wherein said predetermined adjacent PH transmits to said spare PH a list of reference numbers of virtual circuit connections to be served by said predetermined adjacent PH, to form a list of reserved numbers in said spare PH.
Claim 4
Dependent Claim
39 words
The method of claim 3 wherein when said spare PH receives a message, it tests whether a reference number of said message is a reserved number, and, if so, transmits said message to said predetermined adjacent PH for service.
Claim 5
Dependent Claim
25 words
The method of claim 4 wherein if said test indicates that said reference number is not a reserved number, said spare PH processes said message.
Claim 6
Dependent Claim
47 words
The method of claim 5 wherein when said predetermined adjacent PH releases a connection having the logical PH number of said failed serving PH, it transmits a reference number of that connection to said spare PH, to remove that reference number from said list of reserved numbers.
Claim 7
Dependent Claim
31 words
The method of claim 1 wherein when said spare PH takes the role of said failed serving PH, it is connected to receive messages originally destined for said failed serving PH.
Claim 8
Dependent Claim
25 words
The method of claim 1 wherein when said serving PH fails, said predetermined adjacent PH restarts timers for stable connections from the failed serving PH.
Claim 9
Dependent Claim
29 words
The method of claim 1 wherein when said spare PH takes the role of said failed serving PH, it takes the logical PH number of said failed serving PH.
Claim 10
Dependent Claim
90 words
Apparatus for maintaining stable virtual circuit connections comprising: an interconnected group of protocol handlers, connectable to message sources and destinations, each for storing state information for stable virtual circuit connections in a predetermined adjacent PH; means for connecting a spare PH to message sources and destinations of a failed serving PH; said predetermined adjacent PH for serving connections for messages already active at a time when said serving PH failed; and said spare PH for transmitting to said predetermined adjacent PH messages of virtual circuit connections served by that PH.
Claim 11
Dependent Claim
61 words
The apparatus of claim 10 wherein following a failure of said serving PH, said predetermined adjacent PH transmits to said spare PH a list of reference numbers of stable virtual circuit connections to be served by said predetermined adjacent PH and said spare PH transmits to said predetermined adjacent PH any received messages having one of said list of reference numbers.
Claim 12
Dependent Claim
29 words
The apparatus of claim 10 wherein following a failure of said serving PH, said predetermined adjacent PH starts timers for stable connections formerly served by said failed serving PH.
References Cited (Backward Citations)
No citation records indexed.
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