Automatically detecting best paths from shadow route reflectors

A non-transitory computer-readable storage medium storing one or more sequences of instructions which, when executed by one or more processors comprising a data packet router, cause the one or more processors to perform:

• receiving, at the data packet router, a path advertisement comprising information about an available path and a well-known community value associated with the available path, wherein the well-known community value indicates a rank of a device that computed the available path;
• comparing the community value associated with the available path with a router community value assigned to the data packet router which received the path advertisement to determine whether the community value associated with the available path is lesser than the router community value assigned to the data packet router;
• in response to determining that the community value associated with the available path is lesser than the router community value assigned to the data packet router, computing, using data stored in a connectivity database, a particular best path that is different from the available path;
• in response to determining that the well-known community value associated with the available path is not lesser than a router-well-known community value associated with the data packet router, storing the information about the available path in the connectivity database, computing the particular best path using data stored in the connectivity database;
• advertising, to other routers, the particular best path with the router well-known community value associated with the data packet router.

A method performed by one or more processors comprising a reflector, the method comprising:

• receiving, at the reflector, a path advertisement comprising information about an available path and a well-known community value of a device that computed the available path;
• comparing the community value associated with the available path with a router community value assigned to the reflector which received the path advertisement to determine whether the community value associated with the available path is lesser than the router community value assigned to the reflector;
• in response to determining that the community value associated with the available path is lesser than the router community value assigned to the reflector, storing the available path in a connectivity database, computing a best path using data stored in the connectivity database, advertising, to clients, the best path without a restriction indicator, advertising, to non-clients, the best path with the restriction indicator;
• in response to determining that the community value associated with the available path is not lesser than the router community value assigned to the reflector, computing, using the data stored in the connectivity database, a shadow best path that is different from any path learned from a higher-ranked device, advertising, to the clients, the shadow path without the restriction indicator, advertising, to the non-clients, the shadow best path with the restriction indicator.

A non-transitory computer-readable storage medium storing one or more sequences of instructions which, when executed by one or more processors comprising a reflector, cause the one or more processors to perform:

• receiving, at the reflector, a path advertisement comprising information about an available path and a well-known community value of a device that computed the available path;
• comparing the community value associated with the available path with a router community value assigned to the reflector which received the path advertisement to determine whether the community value associated with the available path is lesser than the router community value assigned to the reflector;
• in response to determining that the community value associated with the available path is lesser than the router community value assigned to the reflector, storing the available path in a connectivity database, computing a best path using data stored in the connectivity database, advertising, to clients, the best path without a restriction indicator, advertising, to non-clients, the best path with the restriction indicator;
• in response to determining that the community value associated with the available path is not lesser than the router community value assigned to the reflector, computing, using the data stored in the connectivity database, a shadow best path that is different from any path learned from a higher-ranked device, advertising, to the clients, the shadow path without the restriction indicator, advertising, to the non-clients, the shadow best path with the restriction indicator.