US 6,151,325 A · Method and apparatus for high-capacity circuit switching with an ATM second stage switch

Abstract

A high-capacity multistage switching system includes a second stage ATM switch that interconnects multiple lower-capacity switch modules. The switching system dynamically establishes a connection between the switch ports of two switch modules, using as part of the connection a permanent virtual connection, i.e., a pre-established connection path, through the ATM switch. Each switch module includes one or more switch ports, an ATM interface card and a time-division-multiplexed "TDM" bus that transfers user data between the switch ports and the ATM interface card. A system controller dynamically establishes connections between two given switch ports establishing one or more virtual trunks to transfer the user data between the TDM buses of the switch modules and cell payloads of ATM cells that are directed over the appropriate pre-established connection path through the ATM switch. The system controller then assigns to the connections transmit and receive timeslots on the TDM bus and octets in virtual trunk structures that are associated with the virtual trunks. The ATM card retrieves user data from the transmit timeslots and places the data in the octets of the virtural trunk structures, and then assembles the structures in ATM cells that are directed along the selected connection path. An ATM card that receives an ATM cell disassembles the cell into the constituent virtual trunk structures and retrieves user data from the octets of the structures and places the data on the TDM bus in the receive timeslots.

Claims27

Dependent claims

A multiple stage switching system for use in telecommunications networks, the switching system including:

A. a plurality of switch modules, each switch module including one or more switch ports, an ATM interface card and a time-division-multiplexed "TDM" bus that transfers user data between the switch ports and the ATM interface card;
B. an asynchronous transfer mode "ATM" switch for interconnecting the switch modules, the ATM switch transferring the user data through the switch over pre-established connection paths;
C. a system controller for dynamically establishing connections between the switch ports of the switch modules by establishing for the connections that include a given pair of switch modules one or more virtual trunks to transfer the user data between the TDM buses of the switch modules and cell payloads of ATM cells that are directed over one of the pre-established connection paths in the ATM switch.

An apparatus, comprising:

a first interface which converts information between a first communication protocol and a second communication protocol different from said first communication protocol;
a second interface which converts information between said second communication protocol and a third communication protocol different from said second communication protocol;
a first switch port coupled to said first interface by a pre-established first communication path that carries an ongoing first communication stream which conforms to said first communication protocol and which includes a plurality of selectively assignable portions that can each be selectively populated with user data;
a switching section operatively coupled to each of said first and second interfaces, said switching section having between said first and second interfaces a pre-established second communication path that carries an ongoing second communication stream which conforms to said second communication protocol and which includes a plurality of selectively assignable portions that can each be selectively populated with user data;
a second switch port coupled to said second interface by a pre-established third communication path that carries an ongoing third communication stream which conforms to said third communication protocol and which includes a plurality of selectively assignable portions that can each be selectively populated with user data;
and
system control structure operable to dynamically establish a virtual path for user data between said first and second switch ports by selectively assigning to said virtual path respective said portions in each of said first, second and third communication streams.

4 more elements

An apparatus comprising a switch module which includes:

a pre-established first communication path that carries an ongoing first communication stream which conforms to a first communication protocol and which includes a plurality of selectively assignable portions that can each be selectively populated with user data;
a link adapted to operatively couple said switch module to external structure, said link including a pre-established second communication path that carries an ongoing second communication stream which conforms to a second communication protocol and which includes a plurality of selectively assignable portions that can each be selectively populated with user data, said second communication protocol being different from said first communication protocol;
an interface which is coupled to said link and to said first communication path, and which converts information between said first communication protocol and said second communication protocol;
first and second switch ports which are each coupled to said first communication path;
and
control structure operable to facilitate dynamic establishment of a virtual path for user data from one of said first and second switch ports through said first and second communication paths and said interface by selectively assigning to said virtual path respective said portions in each of said first and second communication streams.

3 more elements

A method of controlling communication between first and second switch ports which are coupled through respective pre-established first and second communication paths and through respective first and second interfaces to a switching section which includes a pre-established third communication path between said interfaces, each of said first, second and third communication paths carrying a respective one of first, second and third ongoing communication streams which each conform to a respective one of first, second and third communication protocols, and which each include a plurality of selectively assignable portions that can each be selectively populated with user data, said third communication protocol being different from said first and second communication protocols, and said interfaces each being operable to convert information between said third communication protocol and a respective one of said first and second communication protocols, said method comprising the step of dynamically establishing a virtual path for user data between said first and second switch ports by selectively assigning to said virtual path respective said portions in each of said first, second and third communication streams.

A computer readable medium encoded with a computer program operable when executed to control communication between first and second switch ports which are coupled through respective pre-established first and second communication paths and through respective first and second interfaces to a switching section which includes between said interfaces a pre-established third communication path, each of said first, second and third communication paths carrying a respective one of first, second and third ongoing communication streams which each conform to a respective one of first, second and third communication protocols, and which each include a plurality of selectively assignable portions that can each be selectively populated with user data, said third communication protocol being different from said first and second communication protocols, and said interfaces each being operable to convert information between said third communication protocol and a respective one of said first and second communication protocols, said control by said computer program of communication between said first and second switch ports including said computer program being operable when executed to dynamically establish a virtual path for user data between said first and second switch ports by selectively assigning to said virtual path respective said portions in each of said first, second and third communication streams.

Dependencies are inferred from the claim text.

Method and apparatus for high-capacity circuit switching with an ATM second stage switch

Life of this patent

Method and apparatus for high-capacity circuit switching with an ATM second stage switch

Life of this patent

Abstract

Claims27