Method and apparatus for sharing a telecommunications channel among multiple users

• US 5,307,347 A
• Filed: 04/10/1992
• Issued: 04/26/1994
• Est. Priority Date: 04/10/1992
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Snyder, Ramon E., Lynch, Jeffrey J., Duault, Maurice
• Primary Examiner(s): Chin, Wellington
• Application Number:
  US07/867,251
• Time in Patent Office: 746 Days
• Field of Search: 370/94.1, 370/94.2, 370/80, 370/60.1, 370/110.1, 370/85.1, 370/85.2, 370/85.3, 370/85.4, 370/85.5, 370/85.15, 370/85.7, 370/85.9, 370/85.11, 370/85.1 2, 340/825.05, 340/825.5, 340/825.51, 340/825.06
• US Class Current: 370/439
• CPC Class Codes: H04Q 11/0428 Integrated services digital network, i.e. systems for transmission of different types of digitised signals, e.g. speech, data, telecentral, television signals

Abstract

A method and an apparatus allows multiple users to share one or more data communication lines without requiring the users to actively participate in the arbitration. The preferred embodiment comprises an ISDN Port Connection Manager (PCM) for managing the use of each of the individual channels of one or more line ports having ISDN service thereon. The ISDN PCM manages the use of the channels between applications using such distinct access methods as IBM'"'"'s Virtual Telecommunications Access Method (VTAM), TCP/IP, and Open Systems Interconnect (OSI) access methods. The ISDN PCM determines that an application needs access to an ISDN channel, determines the availability of the ISDN network and sets up the communication between the application and the network if the channel is available. If no channel is available at that time, the ISDN PCM indicates to the application when the channel becomes available so that the application may determine whether it still needs access.

Claims

1. An apparatus for managing, among multiple users, the use of one or more data communications channels over which said users may communicate with other users, said apparatus comprising means for receiving a request from a user to access a channel of said one or more data communications channels, means for allowing said user to access said channel if said channel is available, and means for informing said user that said channel is unavailable if said channel is unavailable, informing said user that said channel is available when said channel becomes available, determining whether said user still needs access to said channel, and allowing said user to access said channel if said user still needs access to said channel.

2. The apparatus as defined in claim 1, wherein said apparatus communicates with said users via service access points.

3. The apparatus as defined in claim 2, wherein said users are applications utilizing access methods to obtain access to the data communication channels.

4. The apparatus as defined in claim 3, wherein said apparatus operates over the data link and network layers of the Open Systems Interconnect (OSI) standard.

5. The apparatus as defined in claim 4, wherein said apparatus conforms to Link Services Architecture (LSA).

6. The apparatus as defined in claim 1, wherein said data communication channels comprise at least one physical telecommunication line port.

7. The apparatus as defined in claim 6, wherein said data communication channels further comprise an Integrated Services Digital Network (ISDN).

8. A method of managing, among multiple users, the use of a data communications facility through which said users may communicate with other users, said method comprising steps of determining that a user of said multiple users needs access to said facility, determining the availability of said facility, and if said facility is available, allowing said user to access said facility, or if said facility is unavailable, indicating to said user that said facility is unavailable, indicating to said user that said facility is available when said facility becomes available, determining whether said user still needs access to said facility, and allowing said user to access said facility if said user still needs access to said facility.

9. For use in a system for providing communication services by means of an architecture having a plurality of layers, a port connection manager, in one of said layers, said one layer having an adjacent upper layer, for arbitrating the use of a data communication channel between at least two users in said adjacent upper layer comprising:

means for receiving from a requesting user of said at least two users a request for access to said data communication channel;

means for determining if said data communication channel is available for use;

means for allowing said requesting user to access said channel if said channel is available;

means for indicating to said requesting user that said channel is unavailable if said channel is unavailable; and

means for indicating to said requesting user that said data communication channel is available when said data communication channel becomes available and for determining whether said requesting user still needs access to said data communication channel.

10. The port connection manager as defined in claim 9, wherein said at least two users each comprise a connection manager for managing its respective connection to said channel.

11. The port connection manager as defined in claim 10, wherein said port connection manager communicates with said connection managers via service access points (SAPs).

12. The port connection manager as defined in claim 11, wherein said port connection manager operates in the data link and network layers of the Open System Interconnect (OSI) reference.

13. The port connection manager as defined in claim 11, wherein said port connection manager communicates with said connection managers by exchanging primitive constructs therewith.

14. The port connection manager as defined in claim 9, wherein said port connection manager arbitrates the use of a plurality of data communication channels, at least a portion of said data communication channels being part of the Integrated Services Digital Network (ISDN).

15. The port connection manager as defined in claim 14, wherein said data communication channels are coupled to said port connection by a plurality of physical line ports.

16. For use in a system for providing communication services by means of an architecture having a plurality of layers, a port connection manager, in one of said layers, said one layer having an adjacent upper layer, for arbitrating the use of a data communication channel between at least two users in said adjacent upper layer comprising:

means for receiving from each requesting user of said at least two users a request for activation of communication between said requesting user and said port connection manager;

means for receiving a call on said data communication channel for one of said users; and

means for directing said call to said user is said user had previously requested for activation of communication.

17. The port connection manager as defined in claim 16, wherein said port connection manager communicates with said connection managers via service access points (SAPs).

18. The port connection manager as defined in claim 17, wherein said port connection manager operates in the data link and network layers of the Open System Interconnect (OSI) reference.

19. The port connection manager as defined in claim 17, wherein said port connection manager communicates with said connection managers by exchanging primitive constructs therewith.

20. The port connection manager as defined in claim 16, wherein said port connection manager arbitrates the use of a plurality of data communication channels, at least a portion of said data communication channels being part of the Integrated Services Digital Network (ISDN).

21. The port connection manager as defined in claim 20, wherein said data communication channels are coupled to said port connection by a plurality of physical line ports.

22. An apparatus for managing, among at least a first and a second user, the use of one or more data communications channels over which said users may communicate with other users, said apparatus comprising:

means for receiving a request from said first user to access a channel of said one or more data communications channels;

means for allowing said first user to access said channel if one of said one or more data communications channels is available;

means for informing said first user that no channel is available if none of said one or more data communications channels is available;

means for receiving a request from said second user to access a channel of said one or more data communications channels;

means for informing said second user that no channel is available if none of said one or more data communications channels is available;

means for informing said first user that a channel is available when a channel of said one or more data communications channels becomes available, for determining whether said first user still needs access to a channel of said one or more data communications channels, and for allowing said first user to access said available channel if said first user needs access to a channel; and

means for informing said second user that a channel of said one or more data communications channels is available if said first user does not need access to said available channel of if another channel of said one or more data communications channels becomes available, for determining whether said second user still needs access to a channel of said one or more data communications channels, and for allowing said second user to access said available channel if said second user needs access to a channel of said one or more data communications channels.