US7269135B2
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US
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Methods and systems for providing redundant connectivity across a network using a tunneling protocol
Assignee: Extreme Networks Inc
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Filing: 2002-04-04
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Granted: 2007-09-11
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Expires: 2022-04-04
Abstract
Abstract Methods and systems for providing redundant network connectivity across a network using a tunneling protocol by dynamically moving a TLS tunnel between master and slave switches based on relative connectivity provided by the switches are disclosed. A standby routing protocol executes on the master and slave switches to monitor the relative connectivity. In response to detecting that the relative connectivity of the slave switch exceeds that of the master switch, the standby routing protocol reverses the roles of the master and slave switches, thus moving the TLS tunnel to the new master switch.
Inventors
- 👤 John Kevin Frick
- 👤 Cedell A. Alexander, Jr.
- 👤 Olen Lee Stokes, Jr.
- 👤 Charles Frederick Burton, III
- 👤 Donald Bruce Grosser, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 13:38
CPC Classifications
H; H04; H04L; H04L45/00; H04L45/28; H04L43/00; H04L43/08; H04L43/0805; H04L43/0811; H04L45/22; H04L45/50; H04L45/76
Claims Analysis
Total Claims: 45
Claim 1
Independent Claim
252 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing path with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming path and a tunnel with the third switch using the movable IP address as an endpoint, wherein monitoring relative connectivity includes monitoring relative connectivity on per VLAN basis.
Claim 2
Independent Claim
252 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing path with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming path and a tunnel with the third switch using the movable IP address as an endpoint, wherein monitoring relative connectivity includes monitoring relative connectivity on per VLAN basis.
Claim 3
Dependent Claim
26 words
The method of claim 1 wherein providing a first and second switches includes providing first and second Ethernet switches as ingress points to an MPLS network.
Claim 4
Dependent Claim
26 words
The method of claim 1 wherein advertising a route for the movable IP address includes advertising the route via the open shortest path first (OSPF) protocol.
Claim 5
Dependent Claim
27 words
The method of claim 1 wherein establishing a tunnel between the first and third switches includes establishing a virtual circuit tunnel between the first and third switches.
Claim 6
Dependent Claim
29 words
The method of claim 1 wherein establishing a tunnel between the first and third switches includes establishing a transparent LAN services (TLS) tunnel between the first and third switches.
Claim 7
Dependent Claim
18 words
The method of claim 1 wherein forwarding traffic over the tunnel includes forwarding VLAN traffic over the tunnel.
Claim 8
Independent Claim
263 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing path with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming oath and a tunnel with the third switch using the movable IP address as an endpoint, wherein monitoring relative connectivity comprises monitoring the relative number of label switched paths between the first and second switches and remote IP addresses.
Claim 9
Independent Claim
263 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing path with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming oath and a tunnel with the third switch using the movable IP address as an endpoint, wherein monitoring relative connectivity comprises monitoring the relative number of label switched paths between the first and second switches and remote IP addresses.
Claim 10
Independent Claim
264 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing path with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming path and a tunnel with the third switch using the movable IP address as an endpoint, wherein monitoring relative connectivity comprises monitoring the relative number of open Ethernet ports provided by the first and second switches to the first network.
Claim 11
Independent Claim
264 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing path with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming path and a tunnel with the third switch using the movable IP address as an endpoint, wherein monitoring relative connectivity comprises monitoring the relative number of open Ethernet ports provided by the first and second switches to the first network.
Claim 12
Independent Claim
283 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing oath with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming path and a tunnel with the third switch using the movable IP address as an endpoint and where the method further comprises, in response to detecting that connectivity of the second switch exceeds that of the first switch, advertising a route of unreachable to the movable IP address and withdrawing labels associated with the incoming path and the tunnel.
Claim 13
Independent Claim
283 words
A method for providing redundant connectivity between remote networks using a tunneling protocol, the method comprising: (a) providing a first switch in a master state and a second switch in a slave state between a first network and an intermediate network; (b) providing a third switch in the master state and a fourth switch in the slave state between a second network and the intermediate network; (c) from the first switch, advertising a route to a movable IP address associating the movable IP address with an interface on the first switch; (d) establishing incoming and outgoing paths and a tunnel over the paths between the first and third switches using the movable IP address as a tunnel endpoint and forwarding traffic between the first and second networks over the tunnel; (e) at the second switch, establishing an outgoing oath with the third switch; (f) monitoring relative connectivity between the first network and the intermediate network provided by the first and second switches; and (g) in response to detecting that the connectivity of the second switch exceeds that of the first switch, dynamically transitioning the first switch to the slave state and the second switch to the master state, wherein transitioning the second switch to the master state includes associating the movable IP address with an interface on the second switch and establishing an incoming path and a tunnel with the third switch using the movable IP address as an endpoint and where the method further comprises, in response to detecting that connectivity of the second switch exceeds that of the first switch, advertising a route of unreachable to the movable IP address and withdrawing labels associated with the incoming path and the tunnel.
Claim 14
Dependent Claim
17 words
The method of claim 1 wherein the first and second networks comprise virtual local area networks (VLANs).
Claim 15
Dependent Claim
20 words
The method of claim 1 wherein establishing incoming and outgoing paths comprises establishing incoming and outgoing MPLS label switched paths.
Claim 16
Dependent Claim
21 words
The method of claim 1 wherein establishing incoming and outgoing paths comprises establishing incoming and outgoing generic route encapsulation (GRE) paths.
Claim 17
Independent Claim
195 words
A system for providing redundant connectivity across a network, the system comprising: (a) a first switch configured to operate in a master state wherein the first switch advertises a route to a movable local endpoint IP address to routers in an intermediate network and establishes incoming and outgoing paths and a tunnel for carrying local network traffic over the intermediate network; (b) a second switch configured to operate in a slave state wherein the second switch establishes a redundant outgoing path across the intermediate network; and (c) standby routing protocol software for executing on the first and second switches for monitoring relative connectivity provided by the switches and dynamically switching the first switch to operate in the slave state and the second switch to operate in the master state in response to detecting that the relative connectivity of the second switch exceeds that of the first switch, wherein the standby routing protocol software counts the relative number of operational ports that each of the first and second switches has with the local network and to move the local endpoint IP address between the first and second switches based on the relative number of operational ports.
Claim 18
Independent Claim
195 words
A system for providing redundant connectivity across a network, the system comprising: (a) a first switch configured to operate in a master state wherein the first switch advertises a route to a movable local endpoint IP address to routers in an intermediate network and establishes incoming and outgoing paths and a tunnel for carrying local network traffic over the intermediate network; (b) a second switch configured to operate in a slave state wherein the second switch establishes a redundant outgoing path across the intermediate network; and (c) standby routing protocol software for executing on the first and second switches for monitoring relative connectivity provided by the switches and dynamically switching the first switch to operate in the slave state and the second switch to operate in the master state in response to detecting that the relative connectivity of the second switch exceeds that of the first switch, wherein the standby routing protocol software counts the relative number of operational ports that each of the first and second switches has with the local network and to move the local endpoint IP address between the first and second switches based on the relative number of operational ports.
Claim 19
Independent Claim
14 words
The system of claims 13 wherein the first and second switches comprise Ethernet switches.
Claim 20
Independent Claim
204 words
A system for providing redundant connectivity across a network, the system comprising: (a) a first switch configured to operate in a master state wherein the first switch advertises a route to a movable local endpoint IP address to routers in an intermediate network and establishes incoming and outgoing paths and a tunnel for carrying local network traffic over the intermediate network; (b) a second switch configured to operate in a slave state wherein the second switch establishes a redundant outgoing path across the intermediate network; and (c) standby routing protocol software for executing to execute on the first and second switches for monitoring relative connectivity provided by the switches and dynamically switching the first switch to operate in the slave state and the second switch to operate in the master state in response to detecting that the relative connectivity of the second switch exceeds that of the first switch, wherein the standby routing protocol software counts the relative number of label switched paths that each of the first and second switches has with a remote IP address across the intermediate network and to move the local endpoint IP address between the first and second switches based on the relative number of label switched paths.
Claim 21
Independent Claim
204 words
A system for providing redundant connectivity across a network, the system comprising: (a) a first switch configured to operate in a master state wherein the first switch advertises a route to a movable local endpoint IP address to routers in an intermediate network and establishes incoming and outgoing paths and a tunnel for carrying local network traffic over the intermediate network; (b) a second switch configured to operate in a slave state wherein the second switch establishes a redundant outgoing path across the intermediate network; and (c) standby routing protocol software for executing to execute on the first and second switches for monitoring relative connectivity provided by the switches and dynamically switching the first switch to operate in the slave state and the second switch to operate in the master state in response to detecting that the relative connectivity of the second switch exceeds that of the first switch, wherein the standby routing protocol software counts the relative number of label switched paths that each of the first and second switches has with a remote IP address across the intermediate network and to move the local endpoint IP address between the first and second switches based on the relative number of label switched paths.
Claim 22
Dependent Claim
16 words
The system of claim 13 wherein the incoming and outgoing paths comprise MPLS label switched paths.
Claim 23
Dependent Claim
17 words
The system of claim 13 wherein the incoming and outgoing paths comprise generic route encapsulation (GRE) paths.
Claim 24
Dependent Claim
136 words
A switch for tunneling traffic across a network, the switch comprising: (a) a first input/output module for receiving traffic from a first network; (b) a second input/output module for tunneling traffic received from the first network to a second network across an intermediate network; (c) a third input/output module for receiving connectivity information from a companion switch; and (d) a standby routing protocol module operatively associated with the input/output modules, for monitoring connectivity information provided by the companion switch and dynamically establishing and tearing down tunnels with the second network based on the connectivity information, wherein the standby routing protocol module monitors connectivity provided by the first and second input/output modules to the first network and compare the connectivity provided by the first and second input/output modules with the connectivity information received from the companion switch.
Claim 25
Dependent Claim
136 words
A switch for tunneling traffic across a network, the switch comprising: (a) a first input/output module for receiving traffic from a first network; (b) a second input/output module for tunneling traffic received from the first network to a second network across an intermediate network; (c) a third input/output module for receiving connectivity information from a companion switch; and (d) a standby routing protocol module operatively associated with the input/output modules, for monitoring connectivity information provided by the companion switch and dynamically establishing and tearing down tunnels with the second network based on the connectivity information, wherein the standby routing protocol module monitors connectivity provided by the first and second input/output modules to the first network and compare the connectivity provided by the first and second input/output modules with the connectivity information received from the companion switch.
Claim 26
Dependent Claim
12 words
The switch of claim 18 wherein the input/output modules comprise Ethernet modules.
Claim 27
Dependent Claim
18 words
The switch of claim 18 wherein the first input/output module is adapted to receive traffic from a VLAN.
Claim 28
Dependent Claim
19 words
The switch of claim 18 wherein the second input/output module is adapted to tunnel traffic over an MPLS network.
Claim 29
Dependent Claim
21 words
The switch of claim 18 wherein the second input/output module is adapted to tunnel layer 2 traffic over the MPLS network.
Claim 30
Dependent Claim
30 words
The switch of claim 22 wherein the second input/output module is adapted to tunnel the layer 2 traffic over the MPLS network using VC tunnels over MPLS label switched paths.
Claim 31
Dependent Claim
55 words
The switch of claim 18 wherein the standby routing protocol module is adapted to move an Internet protocol address from a tunnel associated with the second input/output module to the companion switch in response to determining that connectivity provided by the first and second input/output modules is less than that provided by the companion switch.
Claim 32
Dependent Claim
129 words
A switch for tunneling traffic across a network, the switch comprising: (a) a first input/output module for receiving traffic from a first network; (b) a second input/output module for tunneling traffic received from the first network to a second network across an intermediate network; (c) a third input/output module for receiving connectivity information from a companion switch; and (d) a standby routing protocol module operatively associated with the input/output modules, for monitoring connectivity information provided by the companion switch and dynamically establishing and tearing down tunnels with the second network based on the connectivity information, wherein the standby routing protocol module operates the first and second input/output modules in a master state when connectivity provided by the first and second input/output modules exceeds that provided by the companion switch.
Claim 33
Dependent Claim
129 words
A switch for tunneling traffic across a network, the switch comprising: (a) a first input/output module for receiving traffic from a first network; (b) a second input/output module for tunneling traffic received from the first network to a second network across an intermediate network; (c) a third input/output module for receiving connectivity information from a companion switch; and (d) a standby routing protocol module operatively associated with the input/output modules, for monitoring connectivity information provided by the companion switch and dynamically establishing and tearing down tunnels with the second network based on the connectivity information, wherein the standby routing protocol module operates the first and second input/output modules in a master state when connectivity provided by the first and second input/output modules exceeds that provided by the companion switch.
Claim 34
Dependent Claim
133 words
A switch for tunneling traffic across a network, the switch comprising: (a) a first input/output module for receiving traffic from a first network; (b) a second input/output module for tunneling traffic received from the first network to a second network across an intermediate network; (c) a third input/output module for receiving connectivity information from a companion switch; and (d) a standby routing protocol module operatively associated with the input/output modules, for monitoring connectivity information provided by the companion switch and dynamically establishing and tearing down tunnels with the second network based on the connectivity information, wherein the standby routing protocol module is adapted to operate the first and second input/output modules in a slave state when connectivity provided by the first and second input/output modules is less than that of the companion switch.
Claim 35
Dependent Claim
133 words
A switch for tunneling traffic across a network, the switch comprising: (a) a first input/output module for receiving traffic from a first network; (b) a second input/output module for tunneling traffic received from the first network to a second network across an intermediate network; (c) a third input/output module for receiving connectivity information from a companion switch; and (d) a standby routing protocol module operatively associated with the input/output modules, for monitoring connectivity information provided by the companion switch and dynamically establishing and tearing down tunnels with the second network based on the connectivity information, wherein the standby routing protocol module is adapted to operate the first and second input/output modules in a slave state when connectivity provided by the first and second input/output modules is less than that of the companion switch.
Claim 36
Dependent Claim
119 words
A computer readable medium comprising computer executable instructions for performing. steps comprising: (a) tunneling layer 2 traffic from a first switch across a network to a remote endpoint; (b) comparing connectivity to the remote endpoint provided by the first switch with connectivity to the remote endpoint provided by a second switch; and (c) in response to determining that connectivity of the second switch exceeds that of the first switch, ceasing the tunneling of layer 2 traffic from the first switch and initiating tunneling of the layer 2 traffic from the second switch, wherein comparing connectivity includes comparing the number of label switched paths provided by the first and second switches to a configured set of remote IP address endpoints.
Claim 37
Dependent Claim
119 words
A computer readable medium comprising computer executable instructions for performing. steps comprising: (a) tunneling layer 2 traffic from a first switch across a network to a remote endpoint; (b) comparing connectivity to the remote endpoint provided by the first switch with connectivity to the remote endpoint provided by a second switch; and (c) in response to determining that connectivity of the second switch exceeds that of the first switch, ceasing the tunneling of layer 2 traffic from the first switch and initiating tunneling of the layer 2 traffic from the second switch, wherein comparing connectivity includes comparing the number of label switched paths provided by the first and second switches to a configured set of remote IP address endpoints.
Claim 38
Dependent Claim
28 words
The computer program product of claim 27 wherein tunneling layer 2 traffic includes tunneling layer 2 traffic using virtual circuit (VC) tunnel running over MPLS label switched paths.
Claim 39
Dependent Claim
19 words
The computer program product of claim 27 wherein tunneling layer 2 traffic includes tunneling VLAN traffic across the network.
Claim 40
Dependent Claim
114 words
A computer readable medium comprising computer executable instructions for performing. steps comprising: (a) tunneling layer 2 traffic from a first switch across a network to a remote endpoint; (b) comparing connectivity to the remote endpoint provided by the first switch with connectivity to the remote endpoint provided by a second switch; and (c) in response to determining that connectivity of the second switch exceeds that of the first switch, ceasing the tunneling of layer 2 traffic from the first switch and initiating tunneling of the layer 2 traffic from the second switch, wherein comparing connectivity includes comparing the number of active Ethernet interfaces provided by the first and second switches to a source network.
Claim 41
Dependent Claim
114 words
A computer readable medium comprising computer executable instructions for performing. steps comprising: (a) tunneling layer 2 traffic from a first switch across a network to a remote endpoint; (b) comparing connectivity to the remote endpoint provided by the first switch with connectivity to the remote endpoint provided by a second switch; and (c) in response to determining that connectivity of the second switch exceeds that of the first switch, ceasing the tunneling of layer 2 traffic from the first switch and initiating tunneling of the layer 2 traffic from the second switch, wherein comparing connectivity includes comparing the number of active Ethernet interfaces provided by the first and second switches to a source network.
Claim 42
Dependent Claim
45 words
The computer program product of claim 27 comprising, in response to detecting that the connectivity of the second switch exceeds that of the first switch, tearing down tunnels between the first switch and the remote endpoint and establishing tunnels between the second switch and remote.
Claim 43
Dependent Claim
37 words
The computer program product of claim 27 comprising, in response to detecting that the connectivity of the second switch exceeds that of the first switch, moving an IP address from the first switch to the second switch.
Claim 44
Dependent Claim
149 words
A computer readable medium comprising computer executable instructions from performing steps comprising: (a) tunneling layer 2 traffic from a first switch across a network to a remote endpoint; (b) comparing connectivity to the remote endpoint provided by the first switch with connectivity to the remote endpoint provided by a second switch; and (c) in response to determining that connectivity of the second switch exceeds that of the first switch, ceasing the tunneling of layer 2 traffic from the first switch and initiating tunneling of the layer 2 traffic from the second switch, moving an IP address from the first switch to the second switch, wherein moving an IP address from the first switch to the second switch includes advertising a route of unreachable with regard to the IP address from the first switch and advertising a route with a finite cost for the IP address from the second switch.
Claim 45
Dependent Claim
149 words
A computer readable medium comprising computer executable instructions from performing steps comprising: (a) tunneling layer 2 traffic from a first switch across a network to a remote endpoint; (b) comparing connectivity to the remote endpoint provided by the first switch with connectivity to the remote endpoint provided by a second switch; and (c) in response to determining that connectivity of the second switch exceeds that of the first switch, ceasing the tunneling of layer 2 traffic from the first switch and initiating tunneling of the layer 2 traffic from the second switch, moving an IP address from the first switch to the second switch, wherein moving an IP address from the first switch to the second switch includes advertising a route of unreachable with regard to the IP address from the first switch and advertising a route with a finite cost for the IP address from the second switch.
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USPTO Annuity & Maintenance Windows
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