Abstract: A method for creating a secure network is provided. The method comprises establishing an overlay domain to control routing between overlay edge routers based on an underlying transport network, wherein said establishing comprises running an overlay management protocol to exchange information within the overlay domain; in accordance with the overlay management protocol defining service routes that exist exclusively within the overlay domain wherein each overlay route includes information on at least service availability within the overlay domain; and selectively using the service routes to control routing between the overlay edge routers; wherein the said routing is through the underlying transport network in a manner in which said overlay routes is shared with the overlay edge routers but not with the underlying transport network via the overlay management protocol.

Abstract: In one embodiment, a first router determines whether an interface coupling the first router to one or more second routers is transit-only. When the interface is transit-only, the first router generates an Open Shortest Path First (OSPF) Link State Advertisement (LSA) that includes an address for the interface and a designated network mask. The designated network mask operates as a transit-only identification that indicates the address should not be installed in a Routing Information Base (RIB) upon receipt of the OSPF LSA at the one or more second routers. When the network is not transit-only, the first router generates an OSPF LSA that includes the address for the interface but does not include the designated network mask, to permit installation of the address in a RIB upon receipt of the OSPF LSA at the one or more second routers.

Abstract: In one embodiment, a first router determines whether a network coupling the first router to one or more second routers is transit-only, wherein transit-only indicates connecting only routers to provide for transmission of data from router to router. When the network is transit-only, the first router generates an Open Shortest Path First (OSPF) Link State Advertisement (LSA) that includes an address for the network and a designated network mask. The designated network mast operates as a transit-only identification that indicates the address should not be installed in a Routing Information Base (RIB) upon receipt of the OSPF LSA at the one or more second routers. When the network is not transit-only, the first router generates an OSPF LSA that includes the address for the network but does not include the designated network mask, to permit installation of the address in a RIB upon receipt of the OSPF LSA at the one or more second routers.

Abstract: In one embodiment, a first router determines whether a network coupling the first router to one or more second routers is transit-only, wherein transit-only indicates connecting only routers to provide for transmission of data from router to router. When the network is transit-only, the first router generates an Open Shortest Path First (OSPF) Link State Advertisement (LSA) that includes an address for the network and a designated network mask. The designated network mast operates as a transit-only identification that indicates the address should not be installed in a Routing Information Base (RIB) upon receipt of the OSPF LSA at the one or more second routers. When the network is not transit-only, the first router generates an OSPF LSA that includes the address for the network but does not include the designated network mask, to permit installation of the address in a RIB upon receipt of the OSPF LSA at the one or more second routers.

Abstract: In one embodiment, a Link State Advertisement (LSA) is received from a first router in a network at a second router in the network. The LSA advertises an address of an interface of the first router. The second router determines whether the LSA includes a transit-only identification that indicates the interface of the first router is a transit-only interface. If the LSA does not include a transit-only identification, the second router installs the advertised address of the interface of the first router in a Router Information Base (RIB) of the second router. If the LSA does include a transit-only identification, the second router declines to install the advertised address of the interface of the first router in the RIB of the second router.

Abstract: In one embodiment, a Link State Advertisement (LSA) is received from a first router in a network at a second router in the network. The LSA advertises an address of an interface of the first router. The second router determines whether the LSA includes a transit-only identification that indicates the interface of the first router is a transit-only interface. If the LSA does not include a transit-only identification, the second router installs the advertised address of the interface of the first router in a Router Information Base (RIB) of the second router. If the LSA does include a transit-only identification, the second router declines to install the advertised address of the interface of the first router in the RIB of the second router.

Abstract: In one embodiment, a network node of a secondary network receives a message from a multi-homed network. The message includes a block of network addresses allocated to the multi-homed network. It is determined that a primary network has advertised an aggregated route including the multi-homed network's allocated block of network addresses. Advertisements of the multi-homed network's allocated block of network addresses are suppressed, after a determination that the primary network has advertised an aggregated route including the multi-homed network's allocated block of network addresses. It may be later be determined that the multi-homed network has lost network connectivity via the primary network. Advertisements of the multi-homed network's allocated block of network addresses are unsuppressed, after a determination that the multi-homed network has lost network connectivity via the primary network.

Abstract: A system for hiding transit-only interfaces in a network. When a routing system is advertising a transit-only interface, the advertisement is marked to indicate the address is a transit-only interface. A routing system receives the advertisement and detects the identifier of the transit-only interface and does not store the address in the Router Information Base of the routing system.

Abstract: In one embodiment, a network node of a secondary network receives a message from a multi-homed network. The message includes a block of network addresses allocated to the multi-homed network. It is determined that a primary network has advertised an aggregated route including the multi-homed network's allocated block of network addresses. Advertisements of the multi-homed network's allocated block of network addresses are suppressed, after a determination that the primary network has advertised an aggregated route including the multi-homed network's allocated block of network addresses. It may be later be determined that the multi-homed network has lost network connectivity via the primary network. Advertisements of the multi-homed network's allocated block of network addresses are unsuppressed, after a determination that the multi-homed network has lost network connectivity via the primary network.

Abstract: A technique for implementing route aggregation in a computer network containing a multi-homed customer site connected to primary and second networks, which in turn are both connected to a common “backbone” network. According to the technique, the primary network allocates a block of network addresses for the customer site, and the customer site notifies the secondary network of its allocated addresses. The secondary network first determines whether the primary network has already advertised an aggregated route which incorporates the customer site's route. If so, the secondary network “suppresses” (i.e., does not advertise) the customer site's route. The secondary network only “unsuppresses” the customer site's route if it detects that the primary network has lost connectivity to the customer site and/or the backbone network.

Abstract: A system for hiding transit-only interfaces in a network. When a routing system is advertising a transit-only interface, the advertisement is marked to indicate the address is a transit-only interface. A routing system receives the advertisement and detects the identifier of the transit-only interface and does not store the address in the Router Information Base of the routing system.