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EP0511671A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

System for monitoring ATM cross-connecting apparatus by inside-apparatus monitoring cell

Assignee: Fujitsu Ltd
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Filing: 1992-04-30
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Granted: —
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Expires: 2012-04-30
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Abstract

Abstract A system for monitoring an ATM cross-connecting apparatus by inputting a test cell through a path for a main signal into the ATM cross-connecting apparatus, and examining the cell after the cell passed through the ATM cross-connecting apparatus. An initial value of a PN sequence and the PN sequence generated based on the initial bit sequence is written in the test cell before inputting to the ATM cross-connecting apparatus. When examining the test cell, the initial bit sequence and the PN sequence are read from the cell, a PN sequence is generated based on the initial bit sequence, and is then compared with the PN sequence read from the test cell to detect an error in the test cell. In addition, a bit pattern indicating a primitive polynomial to generate the PN sequence may be written in the test cell. In this case, the bit pattern is used for generating the PN sequence when examining the test cell. Further, the same VPI values may be written in both the header and the information field of the test cell before inputting the cell to the ATM cross-connecting apparatus, and the VPI value in the information field is compared with a VPI value in the header of the test cell when examining the test cell.

Inventors

  • 👤 Hidetoshi c/o Fujitsu Limited Naito
  • 👤 Masaaki C/O Fujitsu Limited Kawai
  • 👤 Hisako c/o Fujitsu Limited Watanabe
  • 👤 Yuji c/o Fujitsu Limited Takizawa
  • 👤 Kazuyuki c/o Fujitsu Limited Tajima
  • 👤 Haruo c/o Fujitsu Limited Yamashita

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-28 08:41
CPC Classifications
H; H04; H04L; H04L49/00; H04L49/30; H04L49/3009; H04L43/00; H04L43/50; H04L49/3081; H04L49/55; H04L49/555; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04L12/00; H04L12/54; H04L12/56; H04L12/5601; H04L2012/5628; H04L2012/5638; H04L2012/5646; H04L2012/5652

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 112 words
A monitoring system for an ATM cross-connecting apparatus (1), for re-writing a VPI of an input cell and outputting the input cell from an output port corresponding to the re-written VPI, comprising: a setting portion (2) for setting an initial value of a PN pattern and the PN pattern based on the initial value, in an information field in an inside-apparatus monitoring cell which is input into said ATM cross-connecting apparatus (1); and a detecting portion (3) for detecting an error in the cell by extracting the cell output from said ATM cross-connecting apparatus (1) and comparing the PN pattern in the cell with a PN pattern based on the initial value.
Claim 2
Dependent Claim 126 words
A monitoring system for an ATM cross-connecting apparatus (1), for re-writing a VPI of an input cell and outputting the input cell from an output port corresponding to the re-written VPI, comprising: a setting portion (2) for setting a bit pattern as a basis of a primitive polynomial, an initial value of a PN pattern, and the PN pattern based on the initial value, in an information field in an inside-apparatus monitoring cell which is input into said ATM cross-connecting apparatus (1); and a detecting portion (3) for detecting an error in the cell by extracting the cell output from said ATM cross-connecting apparatus (1) and comparing the PN pattern in the cell with a PN pattern based on the initial value and the bit pattern.
Claim 3
Dependent Claim 107 words
A monitoring system for an ATM cross-connecting apparatus (1), for re-writing a VPI of an input cell and outputting the input cell from an output port corresponding to the re-written VPI, comprising: a setting portion (2) for setting the same value as the VPI in a header portion of the cell, in an information field in an inside-apparatus monitoring cell which is input into said ATM cross-connecting apparatus (1); and a detecting portion (3) for detecting an error in the cell by extracting the cell output from said ATM cross-connecting apparatus (1) and comparing a VPI in the header portion with the VPI in the information field.

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