US6466548B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hop by hop quality of service measurement system
Assignee: Cisco Technology Inc
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Filing: 1998-10-28
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Granted: 2002-10-15
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Expires: 2018-10-28
Abstract
Abstract Loopback interfaces are put into routers in a packet switched network. When an end to end Quality of Service (QoS) path is not performing adequately, the delay and jitter characteristics are measured for individual network subsystems. An audio signal is converted into a stream of audio packets and sent hop by hop to the different routers in the network having the loopback interface. QoS is determined by looping back the stream of audio packets from the different routers. If necessary, the network is reconfigured according to loopback delay in the individual network subsystems. Reconfiguration can comprise routing telephone calls through different paths in the network or adding additional equipment to increase capacity.
Inventors
- 👤 Cary W. FitzGerald
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:29
CPC Classifications
H; H04; H04L; H04L43/00; H04L43/50; H04L65/00; H04L65/60; H04L65/65; H04L65/80; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/32; H04M3/323; H04M7/00; H04M7/006; H04M7/12; H04M7/1205; H04L65/1066; H04L65/1101
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
92 words
A hop by hop loopback system, comprising: a Voice Over IP gateway connected to the packet switched network for converting audio signals into a stream of audio packets representing a voice stream generated during a telephone call and routing the audio packets through network processing nodes to a destination endpoint in the a packet switched network; and the Voice Over IP gateway using multiple loopback interfaces located in the network processing nodes to selectively loopback the audio packets from different individually selectable loopback interfaces at the network processing nodes to the gateway.
Claim 2
Dependent Claim
92 words
A hop by hop loopback system, comprising: a Voice Over IP gateway connected to the packet switched network for converting audio signals into a stream of audio packets representing a voice stream generated during a telephone call and routing the audio packets through network processing nodes to a destination endpoint in the a packet switched network; and the Voice Over IP gateway using multiple loopback interfaces located in the network processing nodes to selectively loopback the audio packets from different individually selectable loopback interfaces at the network processing nodes to the gateway.
Claim 3
Dependent Claim
48 words
A system according to claim 1 wherein the Voice over IP gateway measures delays in receiving the stream of audio packets back from the different network processing nodes in the packet switched network and selects different conununication paths for sending additional audio packets by comparing the different delays.
Claim 4
Dependent Claim
51 words
A system according to claim 1 including a route table identifying the network processing nodes in different communication paths in the packet switched network containing loopback interfaces, the Voice Over IP gateway identifying different selectable combinations of the network processing nodes in the different communication paths for sending the audio packets.
Claim 5
Dependent Claim
71 words
A system according to claim 1 wherein the Voice Over IP gateway includes audio packet loopback interfaces between each of the following: a telephone interface that receives the audio signals from a telephone; a digital signal processor subsystem that encodes the audio signal into audio packets and decodes the audio packets into audio signals; and an IP packet router that establishes connections for routing the audio packets to the destination endpoint.
Claim 6
Dependent Claim
74 words
A system according to claim 1 wherein the destination endpoint comprises a destination gateway having audio packet loopback interfaces between each of the following: a telephony interface that receives the audio signals from a destination telephone; a digital signal processor subsystem that encodes the audio signals into audio packets and decodes the audio packets into audio signals; and an IP packet router that establishes connections for routing the audio packets to the originating endpoint.
Claim 7
Dependent Claim
36 words
A system according to claim 1 wherein the gateway automatically identifies only the network processing nodes in the packet switched network having loopback interfaces and automatically initiates audio loopbacks only to the identified network processing nodes.
Claim 8
Independent Claim
110 words
A method for detecting quality of service in a packet switched network having network processing nodes connecting together subnetworks, comprising; converting audio signals into a stream of audio packets; sending the stream of audio packets hop by hop to individually selectable different network processing nodes throughout the packet switched network in a selectable order to create different selectable voice traffic conditions; selectively looping back the stream of audio packets from the network processing nodes; and measuring transmission delays for the loopbacked streams of audio packets from the different network processing nodes to determine the quality of audio service of the individual processing nodes and subnetworks in the packet switched network.
Claim 9
Independent Claim
110 words
A method for detecting quality of service in a packet switched network having network processing nodes connecting together subnetworks, comprising; converting audio signals into a stream of audio packets; sending the stream of audio packets hop by hop to individually selectable different network processing nodes throughout the packet switched network in a selectable order to create different selectable voice traffic conditions; selectively looping back the stream of audio packets from the network processing nodes; and measuring transmission delays for the loopbacked streams of audio packets from the different network processing nodes to determine the quality of audio service of the individual processing nodes and subnetworks in the packet switched network.
Claim 10
Dependent Claim
20 words
A method according to claim 7 including adjusting capacity of the packet switched network according to the measured transmission delays.
Claim 11
Dependent Claim
28 words
A method according to claim 8 including adjusting the capacity of the network by reconfiguring the network to reroute telephone calls through loopback paths having smaller transmission delays.
Claim 12
Dependent Claim
69 words
A method according to claim 7 including: generating the audio signals from a local telephone; receiving the audio signals with a telephone network interface in a local voice over IP gateway; encoding the audio signals with a digital signal processor in the local gateway into audio packets; and establishing a connection in the packet switched network through the local gateway for sending the audio packets to a remote telephone.
Claim 13
Dependent Claim
88 words
A method according to claim 7 including: installing a dial map into a local gateway that stores telephone numbers associated with a circuit switched telephone network interface, a digital signal processor and a packetswitched network interface; and initiating a loop back of the audio signals from any selectable one of the circuit switched telephone network interface, digital signal processor and the packet-switched network interface by entering numbers stored by the dial map associated with the circuit switched telephone network interface, digital signal processor and the packet-switched network interface.
Claim 14
Dependent Claim
52 words
A method according to claim 7 including: accessing a routing table that identifies different paths in the packet switched network that include loopback interfaces; and looping back the stream of audio packets hop by hop and one network processing node at a time along different selected paths identified in the routing table.
Claim 15
Dependent Claim
74 words
A method according to claim 7 including the following: automatically calculating routes in the packet switched network between a source gateway and a destination gateway of the audio packets; automatically identifying routers in the packet switched network with loopback interfaces; automatically generating loopback calls to the identified routers; and calculating loopback delays for each of the loopback calls to determine the quality of service of the different sublinks between the routers with loopback interfaces.
Claim 16
Dependent Claim
36 words
A method according to claim 13 including generating the loopback calls until one of the loopback calls exceeds a predetermined delay threshold level and identifying a loopback path where the predetermined delay threshold level was exceeded.
Claim 17
Dependent Claim
120 words
A hop by hop loopback system for a packet switched network having network processing nodes connecting together network subsystems; comprising: a Voice Over IP gateway connected to the packet switched network for converting audio signals into a stream of audio packets representing a voice stream during a phone call and sending the audio packets through the network processing nodes to a destination endpoint in the packet switched network; and a routing table that identifies multiple loopback interfaces located in the network processing nodes that can loopback the audio packets, the Voice Over IP gateway selectively directing the audio packets to individual network processing nodes identified in the routing table for testing individual selectable network subsystems in the packet switched network.
Claim 18
Dependent Claim
120 words
A hop by hop loopback system for a packet switched network having network processing nodes connecting together network subsystems; comprising: a Voice Over IP gateway connected to the packet switched network for converting audio signals into a stream of audio packets representing a voice stream during a phone call and sending the audio packets through the network processing nodes to a destination endpoint in the packet switched network; and a routing table that identifies multiple loopback interfaces located in the network processing nodes that can loopback the audio packets, the Voice Over IP gateway selectively directing the audio packets to individual network processing nodes identified in the routing table for testing individual selectable network subsystems in the packet switched network.
Claim 19
Dependent Claim
27 words
A system according to claim 15 including a dialplan mapper that contains different phone number dialstrings associated with the different loopback locations in the packet switched network.
Claim 20
Dependent Claim
33 words
A system according to claim 16 wherein the dialplan mapper includes a set of test number entries associated with multiple different loopback paths at the loopback locations identified by the phone number entries.
Claim 21
Dependent Claim
122 words
An electronic storage medium containing software for detecting quality of service in a packet switched network having network processing nodes connecting together subnetworks, comprising; code for converting audio signals into a stream of audio packets; code for sending the stream of audio packets hop by hop to individually selectable different network processing nodes throughout the packet switched network in a selectable order to create different selectable voice traffic conditions; code for selectively looping back the stream of audio packets from the network processing nodes; and code for measuring transmission delays for the loopbacked streams of audio packets from the different network processing nodes to determine the quality of audio service of the individual processing nodes and subnetworks in the packet switched network.
Claim 22
Dependent Claim
122 words
An electronic storage medium containing software for detecting quality of service in a packet switched network having network processing nodes connecting together subnetworks, comprising; code for converting audio signals into a stream of audio packets; code for sending the stream of audio packets hop by hop to individually selectable different network processing nodes throughout the packet switched network in a selectable order to create different selectable voice traffic conditions; code for selectively looping back the stream of audio packets from the network processing nodes; and code for measuring transmission delays for the loopbacked streams of audio packets from the different network processing nodes to determine the quality of audio service of the individual processing nodes and subnetworks in the packet switched network.
Claim 23
Dependent Claim
24 words
An electronic storage medium according to claim 18 including code for adjusting capacity of the packet switched network according to the measured transmission delays.
Claim 24
Dependent Claim
32 words
An electronic storage medium according to claim 19 including code for adjusting the capacity of the network by reconfiguring the network to reroute telephone calls through loopback paths having smaller transmission delays.
Claim 25
Dependent Claim
79 words
An electronic storage medium according to claim 18 including: code for generating the audio signals from a local telephone; code for receiving the audio signals with a telephone network interface in a local voice over IP gateway; code for encoding the audio signals with a digital signal processor in the local gateway into audio packets; and code for establishing a connection in the packet switched network through the local gateway for sending the audio packets to a remote telephone.
Claim 26
Dependent Claim
93 words
An electronic storage medium according to claim 18 including: code for installing a dial map into a local gateway that stores telephone numbers associated with a circuit switched telephone network interface, a digital signal processor and a packet-switched network interface; and code for initiating a loopback of the audio signals from any selectable one of the circuit switched telephone network interface, digital signal processor and the packet-switched network interface by entering numbers stored by the dial map associated with the circuit switched telephone network interface, digital signal processor and the packet-switched network interface.
Claim 27
Dependent Claim
58 words
An electronic storage medium according to claim 18 including: code for accessing a routing table that identifies different paths in the packet switched network that include loopback interfaces; and code for looping back the stream of audio packets hop by hop and one network processing node at a time along different selected paths identified in the routing table.
Claim 28
Dependent Claim
84 words
An electronic storage medium according to claim 18 including the following: code for automatically calculating routes in the packet switched network between a source gateway and a destination gateway of the audio packets; code for automatically identifying routers in the packet switched network with loopback interfaces; code for automatically generating loopback calls to the identified routers; and code for calculating loopback delays for each of the loopback calls to determine the quality of service of the different sublinks between the routers with loopback interfaces.
Claim 29
Dependent Claim
42 words
An electronic storage medium according to claim 24 including code for generating the loopback calls until one of the loopback calls exceeds a predetermined delay threshold level and code for identifying a loopback path where the predetermined delay threshold level was exceeded.
Claim 30
Independent Claim
118 words
A system for detecting quality of service in a packet switched network having network processing nodes connecting together subnetworks, comprising; means for converting audio signals into a stream of audio packets; means for sending the stream of audio packets hop by hop to individually selectable different network processing nodes throughout the packet switched network in a selectable order to create different selectable voice traffic conditions; means for selectively looping back the stream of audio packets from the network processing nodes; and means for measuring transmission delays for the loopbacked streams of audio packets from the different network processing nodes to determine the quality of audio service of the individual processing nodes and subnetworks in the packet switched network.
Claim 31
Independent Claim
118 words
A system for detecting quality of service in a packet switched network having network processing nodes connecting together subnetworks, comprising; means for converting audio signals into a stream of audio packets; means for sending the stream of audio packets hop by hop to individually selectable different network processing nodes throughout the packet switched network in a selectable order to create different selectable voice traffic conditions; means for selectively looping back the stream of audio packets from the network processing nodes; and means for measuring transmission delays for the loopbacked streams of audio packets from the different network processing nodes to determine the quality of audio service of the individual processing nodes and subnetworks in the packet switched network.
Claim 32
Dependent Claim
22 words
A system according to claim 26 including means for adjusting capacity of the packet switched network according to the measured transmission delays.
Claim 33
Dependent Claim
30 words
A system according to claim 27 including means for adjusting the capacity of the network by reconfiguring the network to reroute telephone calls through loopback paths having smaller transmission delays.
Claim 34
Dependent Claim
77 words
A system according to claim 26 including: means for generating the audio signals from a local telephone; means for receiving the audio signals with a telephone network interface in a local voice over IP gateway; means for encoding the audio signals with a digital signal processor in the local gateway into audio packets; and means for establishing a connection in the packet switched network through the local gateway for sending the audio packets to a remote telephone.
Claim 35
Dependent Claim
91 words
A system according to claim 26 including: means for installing a dial map into a local gateway that stores telephone numbers associated with a circuit switched telephone network interface, a digital signal processor and a packet-switched network interface; and means for initiating a loopback of the audio signals from any selectable one of the circuit switched telephone network interface, digital signal processor and the packet-switched network interface by entering numbers stored by the dial map associated with the circuit switched telephone network interface, digital signal processor and the packet-switched network interface.
Claim 36
Dependent Claim
56 words
A system according to claim 26 including: means for accessing a routing table that identifies different paths in the packet switched network that include loopback interfaces; and means for looping back the stream of audio packets hop by hop and one network processing node at a time along different selected paths identified in the routing table.
Claim 37
Dependent Claim
82 words
A system according to claim 26 including the following: means for automatically calculating routes in the packet switched network between a source gateway and a destination gateway of the audio packets; means for automatically identifying routers in the packet switched network with loopback interfaces; means for automatically generating loopback calls to the identified routers; and means for calculating loopback delays for each of the loopback calls to determine the quality of service of the different sublinks between the routers with loopback interfaces.
Claim 38
Dependent Claim
40 words
A system according to claim 32 including means for generating the loopback calls until one of the loopback calls exceeds a predetermined delay threshold level and means for identifying a loopback path where the predetermined delay threshold level was exceeded.
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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) | 2005-10-14 | 2006-04-15 | 2006-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-10-14 | 2010-04-15 | 2010-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-10-14 | 2014-04-15 | 2014-10-15 | $7700.00 | Window Closed / Lapsed |