US6445697B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Audio codec reselection for increased port density
Assignee: Cisco Technology Inc
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Filing: 1998-09-25
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Granted: 2002-09-03
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Expires: 2018-09-25
Abstract
Abstract An Internet telephony gateway and method for operating a gateway are disclosed. The gateway is designed with a port to support a predefined maximum number of audio data channels. The gateway contains sufficient processing throughput to operate a first, high quality audio codec on a subset of the channels. However, this throughput is sufficient to operate a second, lower quality audio codec on a greater number of the channels, preferably all of them. The first and second codecs are designed to produce compressed audio data streams that are interoperably decompressable. In operation, the gateway host processor assigns new calls to either the first or second codec, depending on the current traffic being handled by the gateway. If new calls would result in the gateway's processing throughput being exceeded, the host processor may reassign a channel from the first codec to the second codec in order to create processing headroom for the addition of a new channel. Because the codecs are interoperably decompressable, no renegotiation need occur with the far end of the communication channel when a codec is reassigned. This gateway offers the potential for high-quality communication over the maximum number of channels possible, with a natural degradation as the gateway reaches its full channel capacity, using modest processing resources.
Inventors
- 👤 James L. Fenton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:27
CPC Classifications
H; H04; H04M; H04M7/00; H04M7/12; H04M7/1205; H04M7/125; H04M7/006; H04M7/0072
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
172 words
A packet-switched network telephony gateway comprising: a port for sending audio data streams to and receiving audio data streams from a first network, said port having a maximum audio data stream capacity of at least two data streams; a packet switched network interface for formatting the audio data streams into packets for sending over a packet switched network and unformatting packets received from the packet switched network back into the audio data streams; a host processing resource that monitors the number of audio data streams currently handled by the gateway from the first network and the packet switched network and dynamically associates audio data streams received through said port with a codec selected from a set consisting of a first codec and at least one alternate codec that produce interoperably decompressable data streams; and a codec processing resource that compresses the audio data streams using the codec currently selected by the host processing resource for that audio data stream, the packet switched network interface packetizing and unpacketizing the compressed audio data streams.
Claim 2
Dependent Claim
172 words
A packet-switched network telephony gateway comprising: a port for sending audio data streams to and receiving audio data streams from a first network, said port having a maximum audio data stream capacity of at least two data streams; a packet switched network interface for formatting the audio data streams into packets for sending over a packet switched network and unformatting packets received from the packet switched network back into the audio data streams; a host processing resource that monitors the number of audio data streams currently handled by the gateway from the first network and the packet switched network and dynamically associates audio data streams received through said port with a codec selected from a set consisting of a first codec and at least one alternate codec that produce interoperably decompressable data streams; and a codec processing resource that compresses the audio data streams using the codec currently selected by the host processing resource for that audio data stream, the packet switched network interface packetizing and unpacketizing the compressed audio data streams.
Claim 3
Dependent Claim
14 words
The gateway of claim 1 , wherein said first network is a circuit-switched network.
Claim 4
Dependent Claim
62 words
The gateway of claim 1 , wherein said codec processing resource has throughput sufficient to perform real-time data compression using said first codec on only a subset of the maximum audio data stream capacity of said port, but sufficient to perform real-time data compression using said at least one alternate codec on the entire maximum audio data stream capacity of said port.
Claim 5
Dependent Claim
41 words
The gateway of claim 1 , wherein said host processing resource changes the codec associated with any particular audio data stream depending upon a number of times the host processing resource has previously changed the codec for the audio data stream.
Claim 6
Dependent Claim
34 words
The gateway of claim 1 , wherein said host processing resource changes the codec associated with any particular audio data stream depending upon whether that particular audio data stream has any current voice activity.
Claim 7
Dependent Claim
32 words
The gateway of claim 1 , wherein said host processing resource comprises a first microprocessor and said codec processing resource comprises a second microprocessor connected to and controlled by said first microprocessor.
Claim 8
Dependent Claim
38 words
The gateway of claim 6 , wherein said codec processing resource further comprises a third microprocessor connected to and controlled by said first microprocessor, and wherein said second and third microprocessors receive audio data streams from said port.
Claim 9
Dependent Claim
23 words
The gateway of claim 7 , wherein said second and third microprocessors can each access any audio data stream received from said port.
Claim 10
Dependent Claim
33 words
The gateway of claim 1 , wherein said host processing resource changes the codec associated with any particular audio data stream according to a quality of service associated with the packet switched network.
Claim 11
Dependent Claim
48 words
The gateway of claim 1 , wherein said first codec and said at least one alternate codec both comprise linear predictive audio data compressors operating at a common output data rate, and wherein said first codec requires at least 50% greater average processing time than said second codec.
Claim 12
Dependent Claim
23 words
The gateway of claim 10 , wherein said audio data compressors both comprise conjugate structure algebraic code excited linear predictive audio data compressors.
Claim 13
Dependent Claim
176 words
A packet-switched network telephony gateway comprising: a port for sending audio data streams to and receiving audio data streams from a circuit-switched network, said port having a maximum audio data stream capacity of at least two data streams; at least two digital signal processors; a time-division-multiplexed data bus connected between said port and said digital signal processors, allowing any one of said digital signal processors to access any audio data stream received through said port; a packet switched network interface for packetizing and depacketing the data streams for communicating over a packet switched network; and a host processor that monitors the number of audio data streams handled by the gateway, associates each new audio data stream received through said port with one of said digital signal processors for compression, and dynamically associates each audio data stream received through said port with a codec selected from the set consisting of a first codec and a second codec that produce interoperably decompressable data streams according to a number of active audio channels established over the packet switched network.
Claim 14
Dependent Claim
176 words
A packet-switched network telephony gateway comprising: a port for sending audio data streams to and receiving audio data streams from a circuit-switched network, said port having a maximum audio data stream capacity of at least two data streams; at least two digital signal processors; a time-division-multiplexed data bus connected between said port and said digital signal processors, allowing any one of said digital signal processors to access any audio data stream received through said port; a packet switched network interface for packetizing and depacketing the data streams for communicating over a packet switched network; and a host processor that monitors the number of audio data streams handled by the gateway, associates each new audio data stream received through said port with one of said digital signal processors for compression, and dynamically associates each audio data stream received through said port with a codec selected from the set consisting of a first codec and a second codec that produce interoperably decompressable data streams according to a number of active audio channels established over the packet switched network.
Claim 15
Dependent Claim
67 words
The gateway of claim 12 , wherein said at least two digital signal processors have a combined throughput sufficient to perform real-time data compression using said first codec on only a subset of the maximum audio data stream capacity of said port, but sufficient to perform real-time data compression using said at least one alternate codec on the entire maximum audio data stream capacity of said port.
Claim 16
Dependent Claim
40 words
The gateway of claim 12 , wherein said host processor changes the codec associated with any particular audio data stream according to a number of times the host processor has previously changed the codec associated with the audio data stream.
Claim 17
Dependent Claim
32 words
The gateway of claim 12 wherein the host processor changes the codec associated with any particular audio data stream depending upon whether that particular audio data stream has any current voice activity.
Claim 18
Dependent Claim
31 words
The gateway of claim 12 wherein the host processor changes the codec associated with any particular audio data stream according to a quality of service associated with the packet switched network.
Claim 19
Independent Claim
129 words
A system comprising: means for sending audio data streams to and receiving audio data streams from a packet switched network through a port having a maximum audio data stream capacity of at least two data streams; means for monitoring the number of audio data streams currently handled by the port and dynamically associating audio data streams received through said port with a codec selected from a set consisting of a first codec and at least one alternate codec that produce interoperably decompressable data streams according to the number of audio data streams on the packet switched network handled by the port; means for compressing each audio data stream using the codec currently selected for that audio data stream; and means for packetizing and depacketing the compressed audio data stream.
Claim 20
Independent Claim
129 words
A system comprising: means for sending audio data streams to and receiving audio data streams from a packet switched network through a port having a maximum audio data stream capacity of at least two data streams; means for monitoring the number of audio data streams currently handled by the port and dynamically associating audio data streams received through said port with a codec selected from a set consisting of a first codec and at least one alternate codec that produce interoperably decompressable data streams according to the number of audio data streams on the packet switched network handled by the port; means for compressing each audio data stream using the codec currently selected for that audio data stream; and means for packetizing and depacketing the compressed audio data stream.
Claim 21
Dependent Claim
38 words
The system of claim 17 including means for changing the codec associated with any particular audio data stream according to a number of times the host processing resource has previously changed the codec for the audio data stream.
Claim 22
Dependent Claim
31 words
The system of claim 17 including means for changing the codec associated with any particular audio data stream depending upon whether that particular audio data stream has any current voice activity.
Claim 23
Dependent Claim
30 words
The system of claim 17 including means for changing the codec associated with any particular audio data stream according to a quality of service associated with the packet switched network.
Claim 24
Dependent Claim
139 words
An electronic storage medium containing software used for processing audio data streams, comprising: code for sending audio data streams to and receiving audio data streams from a packet switched network through a port having a maximum audio data stream capacity of at least two data streams; code for monitoring the number of audio data streams currently handled by the port and dynamically associating audio data streams received through said port with a codec selected from a set consisting of a first codec and at least one alternate codec that produce interoperably decompressable data streams according to the number of audio data streams on the packet switched network handled by the port; code for compressing each audio data stream using the codec currently selected for that audio data stream; and code for packetizing and depacketing the compressed audio data stream.
Claim 25
Dependent Claim
139 words
An electronic storage medium containing software used for processing audio data streams, comprising: code for sending audio data streams to and receiving audio data streams from a packet switched network through a port having a maximum audio data stream capacity of at least two data streams; code for monitoring the number of audio data streams currently handled by the port and dynamically associating audio data streams received through said port with a codec selected from a set consisting of a first codec and at least one alternate codec that produce interoperably decompressable data streams according to the number of audio data streams on the packet switched network handled by the port; code for compressing each audio data stream using the codec currently selected for that audio data stream; and code for packetizing and depacketing the compressed audio data stream.
Claim 26
Dependent Claim
40 words
The electronic storage medium of claim 21 including code for changing the codec associated with any particular audio data stream according to a number of times the host processing resource has previously changed the codec for the audio data stream.
Claim 27
Dependent Claim
33 words
The electronic storage medium of claim 21 including code for changing the codec associated with any particular audio data stream depending upon whether that particular audio data stream has any current voice activity.
Claim 28
Dependent Claim
32 words
The electronic storage medium of claim 21 including code for changing the codec associated with any particular audio data stream according to a quality of service associated with the packet switched network.
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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) | 2005-09-02 | 2006-03-04 | 2006-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-09-02 | 2010-03-04 | 2010-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-09-02 | 2014-03-04 | 2014-09-03 | $7700.00 | Window Closed / Lapsed |