US6154448A
Expired / Lapsed
US
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Next hop loopback
Assignee: Telefonaktiebolaget LM Ericsson AB
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Filing: 1997-06-20
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Granted: 2000-11-28
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Expires: 2017-06-20
Abstract
Abstract In a telecommunications network, broken connections can be detected and located through a next hop loopback technique. The next hop loopback technique involves the generation, transmission, and analysis of specialized data packets which attempt to traverse a telecommunications connection, node by node. The failure of a data packet to properly traverse a link can then be used to determine whether a connection is broken, to notify the network management system as to the location of the broken connection, and whether appropriate action is warranted so that the network operator can re-route data around that portion of the network. In addition, the next hop loopback technique can be triggered on an "as needed" basis by the end user, rather than on a periodic basis, thereby conserving network time and resources.
Inventors
- 👤 Lars-Goran Petersen
- 👤 Juan Noguera-Rodriguez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 00:50
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04L12/54; H04L12/56; H04L12/5601; H04L2012/5625; H04L2012/5627
Claims Analysis
Total Claims: 58
Claim 1
Independent Claim
126 words
A method for detecting a failure in a telecommunications network comprising the steps of: forwarding a first communication packet from a first node to a second node adjacent to the first node in a first direction along a communication path; forwarding the first communication packet from the second node to a third node adjacent to the second node in the first direction along the communication path; transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and generating a fault signal indicating a failure between the first node and the second node if the second communication packet is not received by the first node within a predetermined period of time.
Claim 2
Independent Claim
126 words
A method for detecting a failure in a telecommunications network comprising the steps of: forwarding a first communication packet from a first node to a second node adjacent to the first node in a first direction along a communication path; forwarding the first communication packet from the second node to a third node adjacent to the second node in the first direction along the communication path; transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and generating a fault signal indicating a failure between the first node and the second node if the second communication packet is not received by the first node within a predetermined period of time.
Claim 3
Dependent Claim
50 words
The method of claim 1 further comprising the step of: transmitting a third communication packet from the first node to a source node, if the second communication packet is not received by the first node, wherein the third communication packet informs the source node that a fault has been detected.
Claim 4
Dependent Claim
26 words
The method of claim 2, wherein the third communication packet is transmitted along the communication path in a second direction that is opposite the first direction.
Claim 5
Dependent Claim
29 words
The method of claim 1, wherein the predetermined period of time is measured from when the first communication packet is forwarded from the first node to the second node.
Claim 6
Dependent Claim
29 words
The method of claim 4 further comprising the step of: setting a timing counter when the first communication packet is forwarded from the first node to the second node.
Claim 7
Independent Claim
162 words
A method for detecting a failure in a telecommunications network comprising the steps of: forwarding a first communication packet in the direction of a destination node from a first node to a second node adjacent to the first node, wherein the second node is located along a communication path between the first node and the destination node; setting a timing counter in the first node when the first node forwards the first communication packet to the second node; forwarding the first communication packet along the communication path in the direction of the destination node from the second node to a next node adjacent to the second node; transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and generating a fault message if the second communication packet is not received by the first node within a predetermined period of time as measured by the timing counter.
Claim 8
Independent Claim
162 words
A method for detecting a failure in a telecommunications network comprising the steps of: forwarding a first communication packet in the direction of a destination node from a first node to a second node adjacent to the first node, wherein the second node is located along a communication path between the first node and the destination node; setting a timing counter in the first node when the first node forwards the first communication packet to the second node; forwarding the first communication packet along the communication path in the direction of the destination node from the second node to a next node adjacent to the second node; transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and generating a fault message if the second communication packet is not received by the first node within a predetermined period of time as measured by the timing counter.
Claim 9
Dependent Claim
62 words
The method of claim 6 further comprising the step of: transmitting a third communication packet from the first node to a source node if the second communication packet is not received by the first node within the predetermined period of time, wherein the third communication packet informs the source node that a failure has been detected between the first and second nodes.
Claim 10
Dependent Claim
13 words
The method of claim 6, wherein the first node is a source node.
Claim 11
Dependent Claim
22 words
The method of claim 6 further comprising the step of: forwarding the fault message from the first node to a network manager.
Claim 12
Dependent Claim
117 words
The method of claim 6 further comprising the steps of: forwarding the first communication packet along the communication path, node by node, from the next node to the destination node; at the next node, the destination node, and each node located between the next node and the destination node, if any, transmitting another second communication packet to an adjacent node located along the communication path towards a source node in response to receiving the first communication packet; and at the second node, the next node and each node between the next node and the destination node, if any, generating a fault message if the another second communication packet is not received within a predetermined period of time.
Claim 13
Dependent Claim
69 words
The method of claim 10 further comprising the steps of: at the second node, the next node and each node between the next node and the destination node, if any, transmitting a third communication packet to the source node if the another second communication packet is not received within the predetermined period of time, wherein the third communication packet informs the source node that a fault has been detected.
Claim 14
Dependent Claim
13 words
The method of claim 11, wherein the first node is the source node.
Claim 15
Dependent Claim
44 words
The method of claim 10 further comprising the step of: at the second node, the next node and each node between the next node and the destination node, if any, transmitting the fault message to a network manager if the fault message is generated.
Claim 16
Independent Claim
181 words
A method for detecting and locating broken connections in a telecommunication network comprising a source node, a destination node and at least one intermediate node located along a communication path between the source node and the destination node, said method comprising the steps of: generating a forward loopback packet in the source node; forwarding the forward loopback packet, node by node, from the source node to the destination node along the communication path; at each of the at least one intermediate nodes, transmitting a backward loopback packet towards the source node to an adjacent node located along the communication path, if the at least one intermediate node received the forward loopback packet; at the destination node, transmitting another backward loopback packet towards the source node to an adjacent node located along the communication path, if the destination node received the forward loopback packet; and at the source node and each of the at least one intermediate nodes, generating a fault message if the backward loopback packet or the another backward loopback packet is not received within a predetermined period of time.
Claim 17
Independent Claim
181 words
A method for detecting and locating broken connections in a telecommunication network comprising a source node, a destination node and at least one intermediate node located along a communication path between the source node and the destination node, said method comprising the steps of: generating a forward loopback packet in the source node; forwarding the forward loopback packet, node by node, from the source node to the destination node along the communication path; at each of the at least one intermediate nodes, transmitting a backward loopback packet towards the source node to an adjacent node located along the communication path, if the at least one intermediate node received the forward loopback packet; at the destination node, transmitting another backward loopback packet towards the source node to an adjacent node located along the communication path, if the destination node received the forward loopback packet; and at the source node and each of the at least one intermediate nodes, generating a fault message if the backward loopback packet or the another backward loopback packet is not received within a predetermined period of time.
Claim 18
Dependent Claim
46 words
The method of claim 14 further comprising the step of: at the source node and each of the at least one intermediate nodes, setting a timing counter when the forward loopback packet is forwarded towards the destination node to a next node along the communication path.
Claim 19
Dependent Claim
33 words
The method of claim 15, wherein the predetermined period of time is measured by the timing counters at the source node and at each of the at least one of the intermediate nodes.
Claim 20
Dependent Claim
70 words
The method of claim 14 further comprising the steps of: at each of the at least one intermediate nodes, generating an acknowledge loopback packet if the backward loopback packet or the another backward loopback packet is not received within the predetermined period of time; and transmitting the acknowledge loopback packet to the source node, wherein the acknowledge loopback packet informs the source node that a broken connection has been detected.
Claim 21
Dependent Claim
14 words
The method of claim 17, wherein the acknowledge loopback packet is an end-to-end packet.
Claim 22
Dependent Claim
47 words
The method of claim 14 further comprising the step of: at the destination node, generating an acknowledge loopback packet; and transmitting the acknowledge loopback packet to the source node, wherein the acknowledge loopback packet informs the source node that the destination node received the forward loopback packet.
Claim 23
Dependent Claim
124 words
The method of claim 14 further comprising the steps of: at an input portion of the at least one intermediate node, generating an intermediate loopback packet upon receiving the forward loopback packet; multiplexing the intermediate loopback packet onto a communication channel shared by the received forward loopback packet; forwarding the intermediate loopback packet on the communication channel towards an output portion of the at least one intermediate node; demultiplexing the intermediate loopback packet from the communication channel if the intermediate loopback packet reaches the output portion of the intermediate node; and generating an acknowledge loopback packet if the at least one intermediate loopback packet does not reach the output portion of the at least one intermediate node within a second predetermined period of time.
Claim 24
Dependent Claim
61 words
The method of claim 20 further comprising the steps of: initiating a second timing counter in the at least one intermediate node when the intermediate loopback packet is generated; and determining whether the intermediate loopback packet reaches the output portion of the at least one intermediate node within the second period of time as a function of the second timing counter.
Claim 25
Dependent Claim
43 words
The method of claim 20 further comprising the step of: transmitting the acknowledge loopback packet to the source node, wherein the acknowledge loopback packet informs the source node that a broken connection internal to the at least one intermediate node has been detected.
Claim 26
Dependent Claim
13 words
The method of claim 14, wherein the telecommunications network employs asynchronous transfer mode.
Claim 27
Dependent Claim
21 words
The method of claim 23, wherein the loopback packets are asynchronous transfer mode, adaptation layer number two, operation and maintenance packets.
Claim 28
Dependent Claim
15 words
The method of claim 14, wherein the forward loopback packet is a segment loopback packet.
Claim 29
Dependent Claim
14 words
The method of claim 14, wherein the backward loopback packets are segment loopback packets.
Claim 30
Independent Claim
133 words
An apparatus for detecting a failure in a telecommunications network comprising: means for forwarding a first communication packet from a first node to a second node adjacent to the first node in a first direction along a communication path; means for forwarding the first communication packet from the second node to a third node adjacent to the second node in the first direction along the communication path; means for transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and first logic means for generating a fault signal indicating a failure between the first node and the second node if the second communication packet is not received by the first node within a predetermined period of time.
Claim 31
Independent Claim
133 words
An apparatus for detecting a failure in a telecommunications network comprising: means for forwarding a first communication packet from a first node to a second node adjacent to the first node in a first direction along a communication path; means for forwarding the first communication packet from the second node to a third node adjacent to the second node in the first direction along the communication path; means for transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and first logic means for generating a fault signal indicating a failure between the first node and the second node if the second communication packet is not received by the first node within a predetermined period of time.
Claim 32
Dependent Claim
49 words
The apparatus of claim 27 further comprising: means for transmitting a third communication packet from the first node to a source node, if the second communication packet is not received by the first node, wherein the third communication packet informs the source node that a fault has been detected.
Claim 33
Dependent Claim
26 words
The apparatus of claim 28, wherein the third communication packet is transmitted along the communication path in a second direction that is opposite the first direction.
Claim 34
Dependent Claim
29 words
The apparatus of claim 27, wherein the predetermined period of time is measured from when the first communication packet is forwarded from the first node to the second node.
Claim 35
Dependent Claim
30 words
The apparatus of claim 30 further comprising: second logic means for setting a timing counter when the first communication packet is forwarded from the first node to the second node.
Claim 36
Independent Claim
173 words
An apparatus for detecting a failure in a telecommunications network comprising: means for forwarding a first communication packet in the direction of a destination node from a first node to a second node adjacent to the first node, wherein the second node is located along a communication path between the first node and the destination node; first logic means for setting a timing counter in the first node when the first node forwards the first communication packet to the second node; means for forwarding the first communication packet along the communication path in the direction of the destination node from the second node to a next node adjacent to the second node; means for transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and second logic means for generating a fault message if the second communication packet is not received by the first node within a predetermined period of time as measured by the timing counter.
Claim 37
Independent Claim
173 words
An apparatus for detecting a failure in a telecommunications network comprising: means for forwarding a first communication packet in the direction of a destination node from a first node to a second node adjacent to the first node, wherein the second node is located along a communication path between the first node and the destination node; first logic means for setting a timing counter in the first node when the first node forwards the first communication packet to the second node; means for forwarding the first communication packet along the communication path in the direction of the destination node from the second node to a next node adjacent to the second node; means for transmitting a second communication packet from the second node to the first node in response to reception of the first communication packet from the first node; and second logic means for generating a fault message if the second communication packet is not received by the first node within a predetermined period of time as measured by the timing counter.
Claim 38
Dependent Claim
61 words
The apparatus of claim 32 further comprising: means for transmitting a third communication packet from the first node to a source node if the second communication packet is not received by the first node within the predetermined period of time, wherein the third communication packet informs the source node that a failure has been detected between the first and second nodes.
Claim 39
Dependent Claim
13 words
The apparatus of claim 32, wherein the first node is a source node.
Claim 40
Dependent Claim
21 words
The apparatus of claim 32 further comprising: means for forwarding the fault message from the first node to a network manager.
Claim 41
Dependent Claim
122 words
The apparatus of claim 32 further comprising: means for forwarding the first communication packet along the communication path, node by node, from the next node to the destination node; at the next node, the destination node, and each node located between the next node and the destination node, if any, means for transmitting another second communication packet to an adjacent node located along the communication path towards a source node in response to receiving the first communication packet; and at the second node, the next node and each node between the next node and the destination node, if any, third logic means for generating a fault message if the another second communication packet is not received within a predetermined period of time.
Claim 42
Dependent Claim
68 words
The apparatus of claim 36 further comprising: at the second node, the next node and each node between the next node and the destination node, if any, means for transmitting a third communication packet to the source node if the another second communication packet is not received within the predetermined period of time, wherein the third communication packet informs the source node that a fault has been detected.
Claim 43
Dependent Claim
13 words
The apparatus of claim 37, wherein the first node is the source node.
Claim 44
Dependent Claim
43 words
The apparatus of claim 36 further comprising: at the second node, the next node and each node between the next node and the destination node, if any, means for transmitting the fault message to a network manager if the fault message is generated.
Claim 45
Independent Claim
192 words
An apparatus for detecting and locating broken connections in a telecommunication network comprising a source node, a destination node and at least one intermediate node located along a communication path between the source node and the destination node, said method comprising: first logic means for generating a forward loopback packet in the source node; means for forwarding the forward loopback packet, node by node, from the source node to the destination node along the communication path; at each of the at least one intermediate nodes, means for transmitting a backward loopback packet towards the source node to an adjacent node located along the communication path, if the at least one intermediate node received the forward loopback packet; at the destination node, means for transmitting another backward loopback packet towards the source node to an adjacent node located along the communication path, if the destination node received the forward loopback packet; and at the source node and each of the at least one intermediate nodes, second logic means for generating a fault message if the backward loopback packet or the another backward loopback packet is not received within a predetermined period of time.
Claim 46
Independent Claim
192 words
An apparatus for detecting and locating broken connections in a telecommunication network comprising a source node, a destination node and at least one intermediate node located along a communication path between the source node and the destination node, said method comprising: first logic means for generating a forward loopback packet in the source node; means for forwarding the forward loopback packet, node by node, from the source node to the destination node along the communication path; at each of the at least one intermediate nodes, means for transmitting a backward loopback packet towards the source node to an adjacent node located along the communication path, if the at least one intermediate node received the forward loopback packet; at the destination node, means for transmitting another backward loopback packet towards the source node to an adjacent node located along the communication path, if the destination node received the forward loopback packet; and at the source node and each of the at least one intermediate nodes, second logic means for generating a fault message if the backward loopback packet or the another backward loopback packet is not received within a predetermined period of time.
Claim 47
Dependent Claim
47 words
The apparatus of claim 40 further comprising: at the source node and each of the at least one intermediate nodes, third logic means for setting a timing counter when the forward loopback packet is forwarded towards the destination node to a next node along the communication path.
Claim 48
Dependent Claim
31 words
The apparatus of claim 41, wherein the predetermined period of time is measured by the timing counters at the source node and at each of the at least one intermediate nodes.
Claim 49
Dependent Claim
73 words
The apparatus of claim 40 further comprising: at each of the at least one intermediate nodes, third logic means for generating an acknowledge loopback packet if the backward loopback packet or the another backward loopback packet is not received within the predetermined period of time; and means for transmitting the acknowledge loopback packet to the source node, wherein the acknowledge loopback packet informs the source node that a broken connection has been detected.
Claim 50
Dependent Claim
14 words
The apparatus of claim 43, wherein the acknowledge loopback packet is an end-to-end packet.
Claim 51
Dependent Claim
50 words
The apparatus of claim 40 further comprising: at the destination node, third logic means for generating an acknowledge loopback packet; and means for transmitting the acknowledge loopback packet to the source node, wherein the acknowledge loopback packet informs the source node that the destination node received the forward loopback packet.
Claim 52
Dependent Claim
141 words
The apparatus of claim 40 further comprising: at an input portion of the at least one intermediate node, third logic means for generating an intermediate loopback packet upon receiving the forward loopback packet; an intermediate loopback multiplexer for multiplexing the intermediate loopback packet onto a communication channel shared by the received forward loopback packet; means for forwarding the intermediate loopback packet on the communication channel towards an output portion of the at least one intermediate node; an intermediate loopback demultiplexer for separating the intermediate loopback packet from the communication channel if the intermediate loopback packet reaches the output portion of the at least one intermediate node; and fourth logic means for generating an acknowledge loopback packet if the intermediate loopback packet does not reach the output portion of the at least one intermediate node within a second predetermined period of time.
Claim 53
Dependent Claim
66 words
The apparatus of claim 46 further comprising: fifth logic means for initiating a second timing counter in the at least one intermediate node when the intermediate loopback packet is generated; and sixth logic means for determining whether the intermediate loopback packet reaches the output portion of the at least one intermediate node within the second period of time as a function of the second timing counter.
Claim 54
Dependent Claim
42 words
The apparatus of claim 46 further comprising: means for transmitting the acknowledge loopback packet to the source node, wherein the acknowledge loopback packet informs the source node that a broken connection internal to the at least one intermediate node has been detected.
Claim 55
Dependent Claim
13 words
The apparatus of claim 40, wherein the telecommunications network employs asynchronous transfer mode.
Claim 56
Dependent Claim
21 words
The apparatus of claim 49, wherein the loopback packets are asynchronous transfer mode, adaptation layer number two, operation and maintenance packets.
Claim 57
Dependent Claim
15 words
The apparatus of claim 40, wherein the forward loopback packet is a segment loopback packet.
Claim 58
Dependent Claim
14 words
The apparatus of claim 40, wherein the backward loopback packets are segment loopback packets.
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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) | 2003-11-28 | 2004-05-29 | 2004-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-28 | 2008-05-29 | 2008-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-28 | 2012-05-29 | 2012-11-28 | $7700.00 | Window Closed / Lapsed |