Methods of communication for expandable telecommunication system

• US 5,737,320 A
• Filed: 05/30/1995
• Issued: 04/07/1998
• Est. Priority Date: 03/08/1994
• Status: Expired due to Term

• Current Assignee: Excel Switching Corp. (Enghouse Systems Limited)
• Original Assignee: Excel Switching Corp. (Enghouse Systems Limited)
• Inventors: Madonna, Robert P.
• Primary Examiner(s): HSU, ALPUS
• Application Number:
  US08/454,411
• Time in Patent Office: 1,043 Days
• Field of Search: 340/825.03, 340/826, 340/825.5, 340/825.51, 340/825.52, 340/825.05, 379/268, 379/269, 379/271, 379/272, 379/273, 370/85.4, 370/85.5, 370/85.12, 370/85.15, 370/352, 370/355, 370/389, 370/395, 370/396, 370/400, 370/401, 370/402, 370/403, 370/404, 370/406, 370/407, 370/408 , 370/428, 370/255, 370/257, 370/258, 370/353, 395/200.11
• US Class Current: 370/258
• CPC Class Codes: H04L 12/43 with synchronous transmission, e.g. time division multiplex [TDM], slotted rings
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 2012/5612 Ring
• CPC Class Codes: H04L 2012/6437 Ring
• CPC Class Codes: H04L 2012/6443 Network Node Interface, e.g. Routing, Path finding
• CPC Class Codes: H04L 2012/6459 Multiplexing, e.g. TDMA, CDMA
• CPC Class Codes: H04L 2012/6475 N-ISDN, Public Switched Telephone Network [PSTN]
• CPC Class Codes: H04L 2012/6481 Speech, voice
• CPC Class Codes: H04L 2012/6486 Signalling Protocols
• CPC Class Codes: H04L 49/105 ATM switching elements
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections
• CPC Class Codes: H04Q 3/002 Details
• CPC Class Codes: Y10S 379/909 Alternatives

Abstract

A means for transferring circuit switched data (CSD) and packet switched data (PSD) in an open, high speed, high bandwidth, expandable telecommunications system having a plurality of switching and non-switching nodes. The network may carry any type of information present in the system including voice, data, video, multimedia, control, configuration and maintenance, and the bandwidth of the network may be divided or shared across various information types. The network provides each node with essentially direct access to information (e.g., circuit switched data, packet switched data, etc.) originating from any port associated with any node served by the network. Different packet structures are provided for communicating circuit switched data, packet switched data, maintenance and control information, and the like. In one method, each node transmits one or more packets, each having an "empty" payload, which is received by other nodes that determine the source of the received packet and the packet'"'"'s status. The receiving node inserts information (if any) it has for the transmitting node into the payload, after which it allows the packet to pass to the next node on the network. The packet traverses the complete network and returns with a "full" payload to the transmitting node, wherein the packet information is captured by the transmitting node. In this fashion, information of any type originating from any port served by any node may be transferred to any other port of the same or different node in the system. In another method, each node uses the network to transmit one or more packets, each of which has a "full" payload that contains information originating from the transmitting node. Each such packet is received by the other nodes, each of which determines the origin of the packet and whether any of the information contained therein is needed by the receiving node. If so, such information is captured from the payload before the packet passes to the next adjacent node. This process is repeated until each node on the network has transmitted one or more packets with a "full" payload and each such packet has traversed the complete network, thereby allowing each node access to the information originated by each other node. These two methods may be combined as well.

Claims

1. A method of transferring information between a plurality of nodes which are connected in communicating relationship by an inter-nodal network to form an expandable telecommunications system, said method comprising the steps of:

(a) transmitting a packet over said inter-nodal network from one of said nodes when said packet is not utilized by another node, said packet containing information identifying said transmitting node, wherein said packet either contains information which said transmitting node intends to transfer to one or more other nodes or having a capacity to carry information;

(b) receiving at one of said one or more other nodes said packet;

(c) determining if said received packet is an empty packet or full packet;

(d) transmitting information destined for said transmitting node via said packet from said receiving node when said received packet is an empty packet;

(e) receiving said information destined for said receiving node at said receiving node when said received packet is full; and

(f) repeating step (a) through (e) at each of said one or more other nodes.

2. The method as in claim 1, wherein said packet comprises:

a source address configured to store said information identifying said transmitting node; and

a payload for containing said information.

3. The method as in claim 2 wherein during said step (a), said transmitting node performs the steps of:

(1) sequentially reading circuit switched data from a local transmitter memory; and

(2) inserting said sequentially read data into said payload, said sequentially read data originating from one or more ports which are physically associated with said transmitting node.

4. The method as in claim 3, wherein during said step (e), said receiving node performs the step of:

(1) selectively retrieving from the packet any information which is destined for said receiving node; and

(2) selectively writing circuit switched data from said payload into a local receiver memory, said selectively written data destined for one or more ports which are physically associated with said receiving node.

5. The method as in claim 3, wherein during said step (a), said transmitting node sequentially performs the steps of:

(3) reading packet switched data from a local transmitter memory;

(4) inserting said sequentially read data into said payload; and

(5) inserting into said packet a destination address which identifies one or more of said other nodes as the intended destination or destinations of said packet switched data.

6. The method as in claim 5, wherein said circuit switched data selectively inserted into said payload at said receiving node during said step (f) comprises circuit switched data which is destined for one or more ports physically associated with said transmitting node.

7. The method as in claim 6, further comprising the step of:

(i) sequentially writing the circuit switched data retrieved from the payload into a local receiver memory at the transmitting node when a transmitted empty packet is returned to said transmitting node.

8. The method of claim 2, wherein said step (f) comprises the steps of:

(1) selectively inserting information destined for said transmitting node into said packet; and

(2) after said step (f)(1), allowing said packet to continue along said inter-nodal network to another node.

9. A method of transferring information between a plurality of nodes which are connected in communicating relationship by an inter-nodal network to form an expandable telecommunications system, said method comprising the steps of:

(a) transmitting a packet over said inter-nodal network from one of said nodes, said packet containing source address information and information, if any, which said transmitting node intends to transfer to each of the remaining nodes;

(b) receiving said packet at a first one of said remaining nodes and selectively extracting any information destined for such receiving node;

(c) repeating step (b) at each of said remaining nodes, in turn, until said packet returns to the transmitting node; and

(d) repeating steps (a) through (c) until each of said nodes has received a packet from every other node.

10. The method as in claim 9 wherein during said step (a), said transmitting node performs the steps of:

(1) sequentially reading circuit switched data from a local transmitter memory; and

(2) inserting said sequentially read data into a payload within said packet, said sequentially read data originating from one or more ports which are physically associated with said transmitting node.

11. The method as in claim 10 wherein said circuit switched data is arranged in a predetermined order within said payload, whereby said receiving node may use said order to determine the ports from which said circuit switched data originated.

12. The method as in claim 9 wherein during step (b), said receiving node performs the step of:

(1) selectively writing circuit switched data from said payload into a local receiver memory, said selectively written data destined for one or more ports which are physically associated with said receiving node.

13. The method as in claim 9 wherein during said step (a), said transmitting node performs the steps of:

(1) reading packet switched data from a local transmitter memory;

(2) inserting said read data into a payload within said packet; and

(3) inserting into said packet a destination address which identifies one or more of said remaining nodes as the intended destination or destinations of said packet switched data.

14. The method as in claim 13 wherein during said step (b), said receiving node performs the steps of:

(1) checking said destination address of said packet; and

(2) writing said packet switched data contained in said payload into a local packet receiver memory when said destination address indicates said packet is destined for said receiving node.

15. The method as in claim 13 wherein during said step (b), the receiving node performs the steps of:

(1) verifying that the destination address indicates that said received packet is destined for said receiving node;

(2) determining if a local packet receiver memory is ready to accept said packet switched data; and

(3) writing said packet switched data contained in said payload into said local packet receiver memory when said local packet receiver memory is ready.

16. The method as in claim 13 wherein during said step (b), the receiving node performs the step of:

(1) verifying that the destination address indicates that said received packet is destined for said receiving node;

(2) determining if a local packet receiver memory is ready to accept said packet switched data; and

(3) forwarding said packet to said transmitting node when said local packet receiver memory is not ready.

17. The method of claim 9, wherein said steps (a) through (d) are completed within 125 microseconds.

18. A method of transferring information between a plurality of nodes which are connected in communicating relationship by an inter-nodal network to form an expandable telecommunications system, said method comprising the steps of:

(a) transmitting a packet over said inter-nodal network from one of said nodes, said packet containing information identifying said transmitting node and having a capacity to carry information;

(b) receiving said packet at a node other than said transmitting node, said receiving node performing the steps of;

(1) selectively inserting information destined for said transmitting node into said packet, and

(2) after said step (b)(1), allowing said packet to continue along said inter-nodal network to another node;

(c) repeating step (b) at each node other than said transmitting node, in turn, until said packet returns to said transmitting node;

(d) at said transmitting node retrieving from said returned packet the information inserted therein by other nodes; and

(e) repeating steps (a) through (d) until each of the plurality of nodes has transmitted a packet and received that returned packet containing information from other nodes.

19. The method as in claim 18 wherein said packet includes a source address which identifies said transmitting node and a payload for carrying said information.

20. The method as in claim 19 wherein during said step (a), said transmitting node performs the steps of:

(1) selectively reading circuit switched data from a local transmitter memory;

(2) inserting said selectively read data into said payload, said selectively read data both originating from and being destined for one or more ports that are physically associated with said transmitting node.

21. The method as in claim 20 wherein said circuit switched data selectively inserted into said payload at said receiving node during said step (b) comprises circuit switched data which is destined for one or more ports physically associated with said transmitting node.

22. The method as in claim 21 wherein said circuit switched data is arranged in a predetermined order within said payload, whereby said receiving node may use said order to determine the ports from which said circuit switched data originated.

23. The method as in claim 20 wherein said step (d) includes the step of:

(1) sequentially writing the circuit switched data retrieved from the payload into a local receiver memory.

24. The method of claim 23, wherein during said step (d) said transmitting node further comprises the following steps before said step (d)(1):

(2) determining that said received packet originated with said transmitting node.

25. The method as in claim 19 wherein during said step (b)(1), said receiving node performs the steps of:

a) prior to said step (b), verifying that packet switched data destined for the transmitting node is ready for transmission; and

b) inserting said packet switched data into said payload when said packet switched data is ready for transmission.

26. The method as in claim 25 wherein during said step (d), the transmitting node performs the step of:

(1) writing the packet switched data contained in said payload into a local packet receiver memory.

27. The method of claim 20 wherein during said step (a) said transmitting node further performs the following step before said step (a)(1):

(3) taking control over said packet when said packet is not utilized by another node and when said transmitting node can transmit said packet during a period of time allocated for nodes to transmit empty circuit switched data packets.

28. The method of claim 21 wherein said step (a)(1) comprises the step of:

(i) writing address and control data from a processor into an address map of said receiving node such that appropriate circuit switched data is selectively inserted into said payload.

29. The method of claim 18 wherein said steps (a) through (d) are completed within 125 microseconds.