Embedded cell loopback method and system for testing in ATM networks
AssigneeADC DSL System, Inc.
InventorsRandall L. Powers, Robert S. Kroninger, Melvin R. Phillips, Dieter H. Nattkemper
Life of this patent
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Abstract
The present invention relates to a method and apparatus for testing components in ATM networks utilizing loop-back based ATM layer testing. The method and apparatus utilize interfaces and identifier codes to send and loop-back test cells along portions of virtual channels to test the virtual channels.
Claims31
A method for determining a status of virtual channels in a cell based network comprising a central office terminal comprising a plurality of interfaces and an ATM switch, a plurality of remote terminals each comprising a plurality of interfaces, and a plurality of end points communicating with an interface of the plurality of remote terminals, the method comprising:
- transmitting a test cell to a first predetermined interface along a first portion of a virtual channel including the first predetermined interface, the test cell being interleaved with data and management cells transmitted along the virtual channel;
- identifying the test cell at the first predetermined interface;
- transmitting a looped back test cell from the first predetermined interface along a second portion of the virtual channel including a second predetermined interface;
- determining if the looped back test cell is received at a specified queue of the central office terminal;
- and
- determining the status of the virtual channel based upon the looped back test cell.
A central office terminal apparatus comprising:
- a plurality of interfaces;
- at least one buffer memory queue selectively associated with the plurality of interfaces, the at least one buffer memory queue adapted to store cells received at and to be transmitted from the associated interfaces;
- an ATM switch in communication with each of the plurality of interfaces and plurality of buffer memory queues, the ATM switch routing and translating cells received at and to be transmitted from the plurality of interfaces;
- and
- a processor in communication with the ATM switch through a processor interface, wherein the processor generates test cells that are transmitted from the central office terminal to a designated interface of a remote terminal or central office terminal along the paths of selected virtual channels available at the central office terminal, that identifies looped back test cells transmitted from the designated interfaces, and that determines a status of virtual channel based upon the returned looped back test cells.
The central office terminal according to claim 111, wherein each test cell comprises an identifier code that indicates the point of loop back.
The central office terminal according to claim 111, wherein a channel between the remote terminal and the central office terminal is an DSL channel.
The central office terminal according to claim 111, wherein the processor generates the test cells at predetermined intervals for transmission along each of the virtual channels.
A method for determining the status of virtual channels provisioned from a central office terminal, the method comprising:
- generating periodic test cells that each comprise an identifier code, the test cells being transmitted from the central office terminal along test paths that comprise portions of the virtual channels provisioned at the central office terminal and including remote terminals;
- determining if the test cells being transmitted from the central office terminal are received as looped back test cells, the determination being made based upon a changed identifier code written in the looped back test cells;
- and
- if the looped back test cells are received at the central office terminal then determining a status of the virtual channels by reading a payload of the looped back test cell.
A method for determining a status of virtual channels in a cell based network comprising a central office terminal and at least one remote terminal, the method comprising:
- transmitting a test cell to a first selected interface of the central office terminal or the at least one remote terminal along a first portion of a virtual channel including the first selected interface;
- identifying the test cell at the first selected interface;
- transmitting a looped back test cell from the first selected interface along a second portion of the virtual channel including at least a second selected interface;
- determining if the looped back test cell is received at a specified queue of the central office terminal;
- and
- determining the status of the virtual channel based upon the looped back test cell.
A method for determining the status of virtual channels provisioned from a central office terminal, the method comprising:
- generating periodic test cells that each comprise an identifier code, the test cells being transmitted from the central office terminal along test paths that comprise portions of the virtual channels provisioned at the central office terminal and including remote terminals;
- determining if the test cells being transmitted from the central office terminal are received as looped back test cells;
- and
- if the looped back test cells are received at the central office terminal then determining a status of the virtual channels by reading a payload of the looped back test cell.
Dependencies are inferred from the claim text.