ATM cell policing method and apparatus

• US 5,828,654 A
• Filed: 05/24/1996
• Issued: 10/27/1998
• Est. Priority Date: 02/06/1992
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd., Nippon Telegraph and Telephone Corporation
• Original Assignee: Hitachi, Ltd., Nippon Telegraph and Telephone Corporation
• Inventors: Takano, Mitsuhiro, Sato, Youichi, Oouchi, Toshiya, Shinada, Shigeo, Yamanaka, Naoaki, Takase, Akihiko
• Primary Examiner(s): VU, HUY DUY
• Application Number:
  US08/653,475
• Time in Patent Office: 886 Days
• Field of Search: 370/230, 370/231, 370/232, 370/233, 370/234, 370/235, 370/229, 370/236, 370/252, 370/397, 370/399, 370/400, 370/409, 370/412, 370/413, 370/414, 370/415, 370/416, 370/417, 370/418, 370/428, 370/429, 370/465, 370/468, 370/473
• US Class Current: 370/233
• CPC Class Codes: H04L 12/5602 Bandwidth control in ATM Networks, e.g. leaky bucket
• CPC Class Codes: H04L 2012/5636 Monitoring or policing, e.g. compliance with allocated rate, corrective actions
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 49/3081 ATM peripheral units, e.g. policing, insertion or extraction
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

In an input cell policing method in a network of an asynchronous transfer mode, according to information contained in a header field of each input cell, a group to which the cell belongs is identified. For each group, there are set a plurality of time frames having a predetermined length and mutually different phases to count the number of input cells in each time frame period. For each time frame, the count value of input cells is compared with a predetermined threshold value. An input cell for which the count value exceeds the threshold value in either one of the time frames is assumed to be an excess cell. The excess cell is discarded or a violation mark is added thereto.

Claims

1. An input cell policing method for use in a network of an asynchronous transfer mode, comprising the steps of:

identifying, according to information contained in a header field of each input cell, one of a plurality of groups of cells to which the input cell belongs;

setting, for each of the groups, respectively monitor periods having substantially the same predetermined length and mutually different phases from each other and counting the number of input cells in each of the monitor periods;

comparing an accumulated value obtained by adding a count value of input cells in a current monitor period to a count value of input cells in a past monitor period consecutive in time to the current monitor period with a predetermined threshold value; and

processing as an excess cell a cell inputted under a condition in which the accumulated value associated therewith exceeds the threshold value as a result of the comparison.

2. A method according to claim 1, further including the step of discarding the excess cell or the step of marking the cell for indicating the cell as an object of discard operation.

3. An input cell policing apparatus for use in a network of an asynchronous transfer mode, comprising:

means for identifying, according to information contained in a header field of each input cell, one of a plurality of groups of cells to which the input cell belongs;

a plurality of traffic monitor means disposed for the respective groups for detecting a violation input cell; and

means for receiving a violation detection signal from either one of the traffic monitor means and processing as an excess cell an input cell associated with the signal,

wherein each of the traffic monitor means includes;

counter means for measuring the number of input cells belonging to the group identified by the identifying means in each of predetermined measuring periods having substantially the same length and different in phase from each other respectively associated therewith,

means for storing therein a cell count value counted by the counter means in at least one of the past measuring periods, and

comparing means for comparing a value resultant from an addition conducted between the past count value stored in the store means and a current count value counted by the counter means with a predetermined threshold value and outputting a violation detection signal when the value exceeds the threshold value.

4. An input cell policing method for use in a network of an asynchronous transfer mode, comprising the steps of:

identifying, according to information contained in a header field of each input cell, one of a plurality of groups of cells to which the input cell belongs;

setting, for each of the groups, respectively a predetermined number of monitor periods having substantially the same predetermined length and different in phase from each other and counting the number of input cells in each of the monitor periods, the number of said monitor periods being independent of the length of the monitor periods;

comparing an accumulated value obtained by adding a count value of input cells in a current monitor period to a count value of input cells in a past monitor period consecutive in time to the current monitor period with a predetermined threshold value; and

processing as an excess cell a cell inputted under a condition in which the accumulated value associated therewith exceeds the threshold value as a result of the comparison.

5. An input cell policing apparatus for use in a network of an asynchronous transfer mode, comprising:

means for identifying, according to information contained in a header field of each input cell, one of a plurality of groups of cells to which the input cell belongs;

a plurality of traffic monitor means disposed for the respective groups for detecting a violation input cell; and

means for receiving a violation detection signal from either one of the traffic monitor means and processing as an excess cell an input cell associated with the signal,

wherein each of the traffic monitor means includes;

counter means for measuring the number of input cells belonging to the group identified by the identifying means in each, of predetermined measuring periods having substantially the same length and different in phase from each other respectively associated therewith, the number of said measuring periods being independent of the length of the measuring periods,

means for storing therein a cell count value counted by the counter means in at least one of the past measuring periods, and

comparing means for comparing a value resultant from an addition conducted between the past count value stored in the store means and a current count value counted by the counter means with a predetermined threshold value and outputting a violation detection signal when the value exceeds the threshold value.

6. An input cell policing method for use in a network of an asynchronous transfer mode, comprising the steps of:

identifying, according to information contained in a header field of each input cell, one of a plurality of groups of cells to which the input cell belongs;

setting, for each of the groups, respectively two monitor periods having substantially the same predetermined length T and different in phase T/2 from each other and counting the number of input cells in each of the two monitor periods;

comparing an accumulated value obtained by adding a count value of input cells in one of the two monitor periods to a count value of input cells in the other of the two monitor periods consecutive in time to the one monitor period with a predetermined threshold value; and

processing as an excess cell a cell inputted under a condition in which the accumulated value associated therewith exceeds the threshold value as a result of the comparison.

7. An input cell policing apparatus for use in a network of an asynchronous transfer mode, comprising:

means for identifying, according to information contained in a header field of each input cell, one of a plurality of groups of cells to which the input cell belongs;

a plurality of traffic monitor means disposed for the respective groups for detecting a violation input cell; and

means for receiving a violation detection signal from either one of the traffic monitor means and processing as an excess cell an input cell associated with the signal,

wherein each of the traffic monitor means includes;

counter means for measuring the number of input cells belonging to the group identified by the identifying means in each of two predetermined measuring periods having substantially the same length T and different in phase T/2 from each other respectively associated therewith,

means for storing therein a cell count value counted by the counter means in one of the two predetermined measuring periods, and

comparing means for comparing a value resultant from an addition conducted between the count value of the one predetermined measuring period stored in the store means and a count value of the other of the two predetermined measuring periods counted by the counter means with a predetermined threshold value and outputting a violation detection signal when the value exceeds the threshold value.