Integrated packetized voice and data switching system

• US 4,958,341 A
• Filed: 03/31/1988
• Issued: 09/18/1990
• Est. Priority Date: 03/31/1988
• Status: Expired due to Term

• Current Assignee: American Telephone & Telegraph Company (AT&T, Inc.), Bell Telephone Laboratories, Inc. (Nokia Corporation)
• Original Assignee: AT&T, Inc.
• Inventors: Weddige, Roanld C., Ulrich, Werner, Hemmady, Jayant G., Lidinsky, William P., Steele, Scott B.
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Chin, Wellington
• Application Number:
  US07/175,547
• Time in Patent Office: 901 Days
• Field of Search: 370/60, 370/94, 370/58, 370/60.1, 370/94.2, 370/58.1
• US Class Current: 370/352
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 2012/5679 Arbitration or scheduling
• CPC Class Codes: H04L 2012/5687 Security aspects
• CPC Class Codes: H04L 49/106 using space switching, e.g. crossbar or matrix
• CPC Class Codes: H04L 49/107 using shared medium
• CPC Class Codes: H04L 49/1515 Non-blocking multistage, e.g. Clos
• CPC Class Codes: H04L 49/1576 Crossbar or matrix
• CPC Class Codes: H04L 49/1584 Full Mesh, e.g. knockout
• CPC Class Codes: H04L 49/205 Quality of Service based
• CPC Class Codes: H04L 49/253 using establishment or release of connections between ports
• CPC Class Codes: H04L 49/256 Routing or path finding in ATM switching fabrics
• CPC Class Codes: H04L 49/30 Peripheral units, e.g. input or output ports
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/3081 ATM peripheral units, e.g. policing, insertion or extraction
• CPC Class Codes: H04L 49/309 Header conversion, routing tables or routing tags
• CPC Class Codes: H04L 49/355 Application aware switches, e.g. for HTTP
• CPC Class Codes: H04L 49/40 Constructional details, e.g. power supply, mechanical construction or backplane
• CPC Class Codes: H04L 49/506 Backpressure
• CPC Class Codes: H04L 49/555 Error detection
• CPC Class Codes: H04L 49/557 Error correction, e.g. fault recovery or fault tolerance
• CPC Class Codes: H04L 49/606 : Hybrid ATM switches, e.g. ATM&STM, ATM&Frame Relay or ATM&IP
• CPC Class Codes: H04L 63/0272 : Virtual private networks

Abstract

A high capacity metropolitan area network (MAN) is described. Data traffic from users is connected to data concentrators at the edge of the network, and is tranmitted over fiber optic data links to a hub where the data is switched. The hub includes a plurality of data switching modules, each having a control means, and each connected to a distributed control space division switch. Advantageously, the data switching modules, whose inputs are connected to the concentrators, perform all checking and routing functions, while the 1024×1024 maximum size space division switch, whose outputs are connected to the concentrators, provides a large fan-out distribution network for reaching many concentrators from each data switching module. Distributed control of the space division switch permits several million connection and disconnection actions to be performed each second, while the pipelined and parallel operation within the control means permits each of the 256 switching modules to process at least 50,000 transactions per second. The data switching modules chain groups of incoming packets destined for a common outlet of the space division switch so that only one connection in that switch is required for transmitting each group of chained packets from a data switching module to a concentrator. MAN provides security features including a port identification supplied by the data concentrators, and a check that each packet is from an authorized source user, transmitting on a port associated with that user, to an authorized desination user that is in the same group (virtual network) as the source user.

This arrangement can also be used to switch voice packets, using a voice interface such as a digital switch and a digital voice signal to voice packet converter. In accordance with one embodiment of the invention, a packet switch is used for switching voice packet outputs of the data switching modules and a circuit switch, such as the space division switch, is used for switching data packet outputs.

Claims

1. A system for switching voice signals comprising:

means for converting said voice signals into voice packets; and

means, connected to said means for converting, for packet switching said voice packets, comprising;

a plurality of input packet handlers and a plurality of output packet handlers;

memory access means for controlling storing and reading of said voice packets, comprising a plurality of memory access controllers for storing consecutive words of a voice packet in consecutive members of a plurality of memory modules; and

means for distributing said voice packets from said plurality of input packet handlers to said plurality of memory access controllers, for chaining packets to be transmitted to a common group of destinations, and for distributing said chained voice packets from said plurality of memory access controllers to said plurality of output packet handlers.

2. A system for switching voice signals comprising:

a plurality of means for converting said voice signals into voice packets; and

a plurality of means, connected to said means for converting, for packet switching said voice packets, comprising;

a plurality of input packet handlers and a plurality of output packet handlers;

memory access means for controlling storing and reading of said voice packets, comprising a plurality of memory access controllers for storing consecutive words of a voice packet in consecutive members of a plurality of memory modules;

means for distributing said voice packets from said plurality of input packet handlers to said plurality of memory access controllers and for distributing said voice packets from said plurality of memory access controllers to said plurality of output packet handlers; and

circuit switch means for switching said voice packets between output packet handlers of said plurality of means for packet switching and ones of a plurality of communication paths;

wherein said means for packet switching said voice packets comprise means for chaining voice packets in groups, each group for connection over one of said communication paths.

3. The system of claim 2 wherein ones of said plurality of communication paths are connectable to a packet to digital voice signal converter.

4. The system of claim 3 wherein said means for converting said voice signals into voice packets is comprised in a digital switching system connectable to customer stations;

said digital switching systems further comprising means for generating signaling information to said means for converting for signaling terminal identification data for switching packets of a voice connection to a customer station, and for generating signaling information to said means for converting for signaling the identity of a requested customer station to a switch serving that requested customer station.

5. A network for switching first packets comprising data and second packets comprising voice signals, comprising:

first data switching means for switching said first and said second packets, received in said first data switching means, to first and second outputs respectively;

circuit switching means connected to said first outputs for further switching said first packets; and

second data switching means connected to said second outputs for further switching said second packets.

6. A system for switching data and voice signals comprising:

digital switching means connectable to customer lines for generating digital speech signals;

means for generating speech channel identification information;

means connected to said digital switching means for converting speech signals into voice packets and responsive to said speech channel identification information for generating headers to said voice packets;

means for concentrating data traffic from and distributing traffic to said means for generating voice packets;

means, connected via data links to said means for concentrating, for packet switching said voice packets comprising;

a plurality of input packet handlers and a plurality of output packet handlers;

memory means for storing said voice packets comprising a plurality of memory modules for storing consecutive words of a voice packet;

means for chaining packets into groups destined for a common means for distributing and for communicating said chaining data to said output packet handlers;

means, controlled by said input packet handlers for distributing said voice packets from said plurality of input packet handlers to said plurality of memory modules and, controlled by said output packet handlers, for assembling said chained groups of voice packets from said plurality of memory modules to said plurality of output packet handlers.

7. The system of claim 6 further comprising:

circuit switching means connected to said means for packet switching for groups of packets from said means for packet switching to ones of data links connected to said means for concentrating data.

8. A method of switching voice and data packets comprising the steps of:

packet switching said voice packets received on inputs of a first packet switch means to first outputs of said first packet switch means and said data packets to second outputs of said first packet switch means;

connecting said first outputs to a circuit switch means and said second outputs to a second packet switch means.

9. A method of switching voice signals comprising the steps of:

converting said voice signals to voice packets;

transmitting said voice packets to an input packet handler of a data switching means;

transmitting data from said input packet handler to a plurality of memory access controllers of said data switching means for controlling storage of voice packets in a plurality of memory modules;

chaining packets into groups having a common intermediate destination; and

transmitting each of said groups from said plurality of memory access controllers to an output data handler of said data switching means for further transmission to one of said intermediate destinations.