Packet protection method and transmission device in ring network, and program therefor
AssigneeNEC Corporation
InventorKazuo Takagi
Life of this patent
Estimating the term…
Abstract
Two transmission devices connected to a link in which a failure occurs turn back a ring. Other transmission device changes a transmission ring of an NNI packet which is a UNI packet whose transmission source is its own transmission device and which had been transmitted through the link before the failure occurs to have a reverse direction. In addition, each transmission device, upon receiving an NNI packet whose transmission destination NNI address is one or any one of a plurality of NNI addresses applied to its own transmission device, outputs the packet to a self-owned tributary port irrespectively of whether it is sent through an inner ring or an outer ring.
Claims26
A packet protection method in a ring network in which a plurality of transmission devices having a tributary port are connected in a ring by an inner ring and an outer ring whose packet transfer directions are different from each other, wherein
- out of two transmission devices connected to a link in which a failure occurs, a transmission device having said link as an output link turns a transmission ring of an NNI packet passing through said link in which the failure occurs back to a reverse transmission ring, and
- each said transmission device, when receiving an NNI packet whose transmission destination NNI address is one or any one of a plurality of NNI addresses applied to its own transmission device, outputs either of said NNI packets sent through said inner ring and through said outer ring to the tributary port that its own transmission device has.
A transmission device connected to an input link and an output link of an inner ring and to an input link and an output link of an outer ring and having a tributary port, comprising:
- means for, when a failure occurs in an output link of the inner ring connected to its own transmission device, outputting an NNI packet applied through an input link of the inner ring to an output link of the outer ring and when a failure occurs in an output link of the outer ring connected to its own transmission device, outputting an NNI packet applied through an input link of the outer ring to an output link of the inner ring, and
- means for, when receiving an NNI packet whose transmission destination NNI address is one or any one of a plurality of NNI addresses applied to its own transmission device, outputting either of NNI packets applied through the inner ring and the outer ring to the tributary port that its own transmission device has.
A transmission device connected to an input link and an output link of an inner ring and to an input link and an output link of an outer ring and having a tributary port, comprising:
- a first link monitor for detecting a failure in an input link of said inner ring,
- a second link monitor for detecting a failure in an input link of said outer ring,
- a first Wrap switch for outputting an NNI packet applied through an input link of said inner ring to an output link of said inner ring at the time of a pass mode and outputting an NNI packet applied through an input link of said inner ring to an output link of said outer ring at the time of a Wrap mode,
- a second Wrap switch for outputting an NNI packet applied through an input link of said outer ring to an output link of said outer ring at the time of the pass mode and outputting an NNI packet applied through an input link of said outer ring to an output link of said inner ring at the time of the Wrap mode,
- a first Agg-Packet switch for holding one or a plurality of NNI addresses applied to its own transmission device and when a transmission destination NNI address of an NNI packet applied through an input link of said inner ring is the one or any one of the plurality of NNI addresses applied to said its own transmission device, outputting said NNI packet to said tributary port,
- a second Agg-Packet switch for holding one or a plurality of NNI addresses applied to its own transmission device and when a transmission destination NNI address of an NNI packet applied through an input link of said outer ring is one or any one of the plurality of NNI addresses applied to said its own transmission device, outputting said NNI packet to said tributary port, and
- a failure information collection & failure section specifying unit for, when said first link monitor or said second link monitor detects a failure, outputting a ring network failure information notification packet indicative of a failure section to an output link of said inner ring or an output link of said outer ring and when a ring network failure information notification packet is applied through an input link of said inner ring or through an input link of said outer ring, if said ring network failure information notification packet indicates the occurrence of a failure in an output link of the inner ring connected to its transmission device, changing said first Wrap switch to the Wrap mode and if said ring network failure information notification packet indicates the occurrence of a failure in an output link of the outer ring connected to its transmission device, changing said second Wrap switch to the Wrap mode.
A program executed on a computer for causing said computer to function as a transmission device connected to an input link and an output link of an inner ring and to an input link and an output link of an outer ring and having a tributary port, comprising the functions of:
- when a failure occurs in an output link of the inner ring connected to its own transmission device, outputting an NNI packet applied through an input link of the inner ring to an output link of the outer ring and when a failure occurs in an output link of the outer ring connected to its own transmission device, outputting an NNI packet applied through an input link of the outer ring to an output link of the inner ring, and
- when receiving an NNI packet whose transmission destination NNI address is one or any one of a plurality of NNI addresses applied to its own transmission device, outputting either of NNI packets applied through the inner ring and the outer ring to the tributary port that its own transmission device has.
Dependencies are inferred from the claim text.