Patent US5493650A successfully refreshed from Google Patents.
US5493650A
Expired / Lapsed
US
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Apparatus and method for monitoring the presence of cables connected to ports of a computer network controller and automatically reconfiguring the network when cables are connected to or removed from the controller
Assignee: Avaya Inc
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Filing: 1994-03-02
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Granted: 1996-02-20
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Expires: 2014-03-02
Abstract
Abstract An apparatus for monitoring whether a cable is coupled to a port of a computer network. A free-running oscillator is initially set to a base frequency when a cable is not coupled to the port. If a cable is subsequently coupled to that port, the inherent capacitance of that cable loads one of the nodes associated with the oscillator. The result of this capacitance is that the oscillator is now running at a lower frequency. A frequency counter and threshold comparator are used to detect whether the oscillator frequency has fallen below a pre-determined frequency threshold. If the oscillator frequency has not fallen below this threshold, the port is not included in the network path. However, if the oscillator frequency has fallen below the threshold, this indicates that a cable has been coupled to the port. Consequently, the trunk port is inserted into the computer network's path.
Inventors
- 👤 Karl Reinke
- 👤 Robert W. Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:02
CPC Classifications
H; H04; H04L; H04L41/00; H04L41/08; H04L41/0803; H04L41/0806; H04L41/0809
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
105 words
In a computer network, a method for determining whether a cable is coupled to a port of said computer network, said method comprising the steps of: setting an oscillator to output a first signal at a first frequency; said oscillator outputting said first signal at a second frequency if said port is loaded with a capacitance from said cable; a comparison circuit comparing said first signal output from said oscillator to a comparison value and generating a second signal responsive to whether said first signal compares to said comparison value; inserting said port in a path of said computer network according to said second signal.
Claim 2
Dependent Claim
105 words
In a computer network, a method for determining whether a cable is coupled to a port of said computer network, said method comprising the steps of: setting an oscillator to output a first signal at a first frequency; said oscillator outputting said first signal at a second frequency if said port is loaded with a capacitance from said cable; a comparison circuit comparing said first signal output from said oscillator to a comparison value and generating a second signal responsive to whether said first signal compares to said comparison value; inserting said port in a path of said computer network according to said second signal.
Claim 3
Dependent Claim
13 words
The method of claim 1, wherein said first frequency is approximately 1.4 MHz.
Claim 4
Dependent Claim
14 words
The method of claim 2, wherein said threshold is set at approximately 1.2 MHz.
Claim 5
Dependent Claim
16 words
The method of claim 1 further comprising the step of providing surge protection for said oscillator.
Claim 6
Dependent Claim
15 words
The method of claim 1 further comprising the step of providing hysteresis for said oscillator.
Claim 7
Independent Claim
111 words
An apparatus for monitoring whether a cable is coupled to a port of a computer network, said apparatus comprising: an oscillator generating an oscillator signal at a first frequency; a frequency indicator coupled to said oscillator for indicating the frequency of said oscillator signal; a comparator coupled to said frequency indicator for comparing the indicated frequency of said oscillator signal to a predetermined frequency, said comparator outputting a cable detect signal whose value is dependent on said comparison; a controller having an input coupled with said comparator to receive said cable detect signal, said controller, responsive to said cable detect signal, coupling said port to a path of said computer network.
Claim 8
Independent Claim
111 words
An apparatus for monitoring whether a cable is coupled to a port of a computer network, said apparatus comprising: an oscillator generating an oscillator signal at a first frequency; a frequency indicator coupled to said oscillator for indicating the frequency of said oscillator signal; a comparator coupled to said frequency indicator for comparing the indicated frequency of said oscillator signal to a predetermined frequency, said comparator outputting a cable detect signal whose value is dependent on said comparison; a controller having an input coupled with said comparator to receive said cable detect signal, said controller, responsive to said cable detect signal, coupling said port to a path of said computer network.
Claim 9
Dependent Claim
13 words
The apparatus of claim 6, wherein said first frequency is approximately 1.4 MHz.
Claim 10
Dependent Claim
25 words
The apparatus of claim 7, wherein said frequency indicator determines the frequency rate of said oscillator signal and said predetermined frequency is approximately 1.2 MHz.
Claim 11
Dependent Claim
22 words
The apparatus of claim 6 further comprising a filter coupled to said port for filtering differential mode signals output from said port.
Claim 12
Dependent Claim
19 words
The apparatus of claim 6 further comprising a plurality of diodes coupled to said oscillator to provide surge protection.
Claim 13
Dependent Claim
18 words
The apparatus of claim 6 further comprising a plurality of resistors coupled to said oscillator to provide hysteresis.
Claim 14
Dependent Claim
14 words
The apparatus of claim 6, wherein said oscillator is comprised of a line receiver.
Claim 15
Dependent Claim
17 words
The apparatus of claim 6 wherein said frequency indicator is coupled to said cable through said oscillator.
Claim 16
Dependent Claim
16 words
The apparatus of claim 6 wherein a wire of the cable is coupled to the oscillator.
Claim 17
Independent Claim
81 words
An apparatus for monitoring whether a cable is coupled to a port of a computer network, said apparatus comprising: an oscillator generating an oscillator signal; a rate detector coupled to said cable for generating a cable detect signal having a value dependent on the frequency of said oscillator signal; a controller having an input coupled with said comparator receive said cable detect signal, said controller, responsive to said cable detect signal, coupling said port to a path of said computer network.
Claim 18
Independent Claim
81 words
An apparatus for monitoring whether a cable is coupled to a port of a computer network, said apparatus comprising: an oscillator generating an oscillator signal; a rate detector coupled to said cable for generating a cable detect signal having a value dependent on the frequency of said oscillator signal; a controller having an input coupled with said comparator receive said cable detect signal, said controller, responsive to said cable detect signal, coupling said port to a path of said computer network.
Claim 19
Dependent Claim
17 words
The apparatus of claim 15, wherein said rate detector also determines whether a received signal is valid.
Claim 20
Dependent Claim
13 words
The apparatus of claim 15, wherein said first frequency is approximately 1.4 MHz.
Claim 21
Dependent Claim
13 words
The apparatus of claim 17, wherein said predetermined frequency is approximately 1.2 MHz.
Claim 22
Dependent Claim
22 words
The apparatus of claim 15 further comprising a filter coupled to said port for filtering differential mode signals output from said port.
Claim 23
Dependent Claim
19 words
The apparatus of claim 15 further comprising a plurality of diodes coupled to said oscillator to provide surge protection.
Claim 24
Dependent Claim
18 words
The apparatus of claim 15 further comprising a plurality of resistors coupled to said oscillator to provide hysteresis.
Claim 25
Dependent Claim
14 words
The apparatus of claim 15, wherein said oscillator is comprised of a line receiver.
Claim 26
Dependent Claim
20 words
The apparatus of claim 15, wherein said cable is comprised of shielded twisted pair wiring or unshielded twisted pair wiring.
Claim 27
Dependent Claim
15 words
The apparatus of claim 23, wherein said computer network is comprised of a token ring.
Claim 28
Dependent Claim
16 words
The apparatus of claim 23 wherein a wire of the cable is coupled to the oscillator.
Claim 29
Dependent Claim
24 words
The apparatus of claim 23 wherein the oscillator signal is coupled to two wires of the twisted pair cable as a common mode signal.
Claim 30
Dependent Claim
16 words
The apparatus of claim 15, wherein said cable has a length of at least 7 feet.
Claim 31
Independent Claim
180 words
An apparatus for reconfiguring a computer network responsive to whether a twisted-pair cable is coupled to a port of the network comprising: a) an oscillator generating an oscillator signal at a first frequency; b) a connector by which a twisted-pair cable may be attached; said connector having an A contact and a B contact; c) a differential line receiver having an A input and a B input and at least one output, the A input of the line receiver being coupled to the A contact of the computer and the B input of the line receiver being coupled to the B contact of the connector, the differential line receiver used to receive data from a computer system; d) a frequency measurement circuit monitoring the frequency of the oscillator signal, the frequency measurement circuit generating a cable detect signal whenever the oscillator is oscillating at the second frequency; e) a controller having an input coupled to the frequency measurement circuit to receive said cable detect signal, the controller, responsive to said cable detect signal, coupling the port of the computer network.
Claim 32
Independent Claim
180 words
An apparatus for reconfiguring a computer network responsive to whether a twisted-pair cable is coupled to a port of the network comprising: a) an oscillator generating an oscillator signal at a first frequency; b) a connector by which a twisted-pair cable may be attached; said connector having an A contact and a B contact; c) a differential line receiver having an A input and a B input and at least one output, the A input of the line receiver being coupled to the A contact of the computer and the B input of the line receiver being coupled to the B contact of the connector, the differential line receiver used to receive data from a computer system; d) a frequency measurement circuit monitoring the frequency of the oscillator signal, the frequency measurement circuit generating a cable detect signal whenever the oscillator is oscillating at the second frequency; e) a controller having an input coupled to the frequency measurement circuit to receive said cable detect signal, the controller, responsive to said cable detect signal, coupling the port of the computer network.
Claim 33
Dependent Claim
16 words
The apparatus of claim 28 wherein a wire of the cable is coupled to the oscillator.
Claim 34
Dependent Claim
24 words
The apparatus of claim 28 wherein the oscillator signal is coupled to two wires of the twisted pair cable as a common mode signal.
Claim 35
Independent Claim
178 words
An apparatus for reconfiguring a computer network responsive to whether a twisted-pair cable is coupled to a port of the network comprising: a) an oscillator generating an oscillator signal at a first frequency; b) a connector by which a twisted-pair cable may be attached, said connector having an A contact and a B contact; c) a differential line drive having an A output and a B output and at least one output, the A output of the line drive being coupled to the A contact of the connector and the B input of the line drive being coupled to the B contact of the connector, the differential line driver used to send data to a computer system; d)frequency measurement circuit monitoring the frequency of the oscillator signal, the frequency measurement circuit generating a cable detect signal whenever the oscillator is oscillating at the second frequency; e) a controller having an input coupled to the frequency measurement means to receive said cable detect signal, the controller, responsive to said cable detect signal coupling the port of the computer network.
Claim 36
Independent Claim
178 words
An apparatus for reconfiguring a computer network responsive to whether a twisted-pair cable is coupled to a port of the network comprising: a) an oscillator generating an oscillator signal at a first frequency; b) a connector by which a twisted-pair cable may be attached, said connector having an A contact and a B contact; c) a differential line drive having an A output and a B output and at least one output, the A output of the line drive being coupled to the A contact of the connector and the B input of the line drive being coupled to the B contact of the connector, the differential line driver used to send data to a computer system; d)frequency measurement circuit monitoring the frequency of the oscillator signal, the frequency measurement circuit generating a cable detect signal whenever the oscillator is oscillating at the second frequency; e) a controller having an input coupled to the frequency measurement means to receive said cable detect signal, the controller, responsive to said cable detect signal coupling the port of the computer network.
Claim 37
Dependent Claim
16 words
The apparatus of claim 28 wherein a wire of the cable is coupled to the oscillator.
Claim 38
Dependent Claim
24 words
The apparatus of claim 31 wherein the oscillator signal is coupled to two wires of the twisted pair cable as a common mode signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-02-19 | 1999-08-21 | 2000-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-02-19 | 2003-08-21 | 2004-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-02-19 | 2007-08-21 | 2008-02-20 | $7700.00 | Window Closed / Lapsed |