US5329519A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lan monitoring method and apparatus
Assignee: Agilent Technologies Inc
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Filing: 1991-11-06
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Granted: 1994-07-12
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Expires: 2011-11-06
Abstract
Abstract A monitoring device detects late packet collision on a CSMA/CD LAN. The device comprises a first detector for detecting the presence of a packet in the LAN, a second detector for detecting the occurrence of a packet collision in the LAN and a late collision indicator which provides a late collision indication whenever the second detector detects the occurrence of a collision more than a predetermined time after the first detector detects the presence of a packet.
Inventors
- 👤 Colin S. I'Anson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 18:08
CPC Classifications
H; H04; H04L; H04L43/00; H04L43/08; H04L43/0823; H04L43/0847; H04W; H04W24/00; H04W24/08; H04W74/00; H04W74/08; H04W84/00; H04W84/02; H04W84/10; H04W84/12
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
141 words
Apparatus for monitoring a CSMA/CD LAN, said apparatus comprising: input means for providing a connection to said LAN to enable monitoring of the LAN whilst operational; first detection means coupled to said input means and operative to detect the presence of a packet on the LAN and to generate a first output signal in response thereto; second detection means coupled to said input means and operative to detect a packet collision on the LAN and to generate a second output signal in response thereto; and late-collision indicator means connected to receive said first and second output signals and operative to provide a late-collision output indication when said second output signal indicates the occurrence of a packet collision subsequent to the elapse of a predetermined time interval from the start of the last preceding packet as indicated by said first output signal.
Claim 2
Dependent Claim
141 words
Apparatus for monitoring a CSMA/CD LAN, said apparatus comprising: input means for providing a connection to said LAN to enable monitoring of the LAN whilst operational; first detection means coupled to said input means and operative to detect the presence of a packet on the LAN and to generate a first output signal in response thereto; second detection means coupled to said input means and operative to detect a packet collision on the LAN and to generate a second output signal in response thereto; and late-collision indicator means connected to receive said first and second output signals and operative to provide a late-collision output indication when said second output signal indicates the occurrence of a packet collision subsequent to the elapse of a predetermined time interval from the start of the last preceding packet as indicated by said first output signal.
Claim 3
Dependent Claim
114 words
Apparatus according to claim 1, wherein said late-collision indicator means comprises: timing means operative to generate an inhibit signal in response to said first output signal indicating the start of a packet on the LAN, said inhibit signal having a duration, from the time said first output signal indicates the start of the last preceding packet, corresponding to said predetermined time interval; and gating means connected to receive said second output signal and said inhibit signal and operative to provide a late-collision signal only when said inhibit signal is absent concurrently with said second output signal being present; the late-collision signal provided by said gating means being used to provide said late-collision output indication.
Claim 4
Dependent Claim
14 words
Apparatus according to claim 2, wherein said timing means is a re-triggerable monostable element.
Claim 5
Dependent Claim
46 words
Apparatus according to claim 2, wherein the late-collision indicator means further comprises an output latch connected to receive the said late-collision signal from the gating means said output latch being operative to latch said late-collision signal on receipt and to thereupon provide said late-collision output indication.
Claim 6
Dependent Claim
21 words
Apparatus according to claim 1, wherein said late-collision indicator means includes means for adjusting the duration of said predetermined time interval.
Claim 7
Dependent Claim
76 words
Apparatus according to claim 1 for use with a LAN that employs a transmission medium adapted to carry electrical signals, wherein: said first detection means is operative to provide said first output signal when the voltage on the LAN exceeds a first predetermined voltage magnitude; and said second detection means is operative to provide said second output signal when the voltage in the LAN exceeds a second predetermined voltage magnitude, greater than said first predetermined magnitude.
Claim 8
Dependent Claim
12 words
Apparatus according to claim 1 in the form of a hand-held instrument.
Claim 9
Independent Claim
89 words
A method of monitoring a CSMA/CD LAN, the method comprising the steps of: detecting the presence of a packet on the LAN and providing a first output signal in response thereto; detecting a packet collision on the LAN and providing a second output signal in response thereto; and providing a late-collision output indication when said second output signal indicates the occurrence of a packet collision subsequent to the elapse of a predetermined time interval from the start of the last preceding packet as indicated by said first output signal.
Claim 10
Independent Claim
89 words
A method of monitoring a CSMA/CD LAN, the method comprising the steps of: detecting the presence of a packet on the LAN and providing a first output signal in response thereto; detecting a packet collision on the LAN and providing a second output signal in response thereto; and providing a late-collision output indication when said second output signal indicates the occurrence of a packet collision subsequent to the elapse of a predetermined time interval from the start of the last preceding packet as indicated by said first output signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-07-11 | 1998-01-10 | 1998-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-11 | 2002-01-10 | 2002-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-11 | 2006-01-10 | 2006-07-12 | $7700.00 | Window Closed / Lapsed |