Apparatus and methods for updating stale link state packets and routing table entries

A first apparatus operable to handle Link State Packets (LSPs) sent between processing nodes within a computer network, the apparatus comprising:

• one or more processors;
• one or more memory, wherein at least one of the processors and memory are adapted for:
• at the first apparatus, receiving a first LSP sent by a second apparatus, wherein the LSP specifies connectivity information regarding the second apparatus;
• determining whether the first received LSP is an updated LSP even when the first received LSP is considered older than another LSP previously sent by the second apparatus to the first apparatus;
• and
• if it is determined that the first received LSP is an updated LSP, performing updating procedures on LSP information that is maintained by the first node, based on the first received LSP, wherein the LSP information was obtained from one or more LSPs sent by the second node, and
• updating the first node's routing tables based on the LSP information maintained by the first node after the updating procedures on the LSP information are performed,
• wherein the determination of whether the received LSP is an updated LSP comprises determining that the received LSP is an updated LSP if (i) authentication succeeds for the received LSP, (ii) the LSP is considered older than another LSP previously stored for the second node, and (iii) the stored LSP fails authentication.

At least one computer readable storage medium having computer program instructions stored thereon that are arranged to perform the following operations:

• at a first node, receiving a first LSP sent by a second node, wherein the LSP specifies connectivity information regarding the second node;
• determining whether the first received LSP is an updated LSP even when the first received LSP is considered older than another LSP previously sent by the second node to the first node;
• and
• if it is determined that the first received LSP is an updated LSP, performing updating procedures on LSP information, that is maintained by the first node, based on the first received LSP, wherein the LSP information was obtained from one or more LSPs sent by the second node, and
• updating the first node's routing tables based on the LSP information maintained by the first node after the updating procedures on the LSP information are performed,
• wherein the determination of whether the received LSP is an updated LSP comprises determining that the received LSP is an updated LSP if (i) authentication succeeds for the received LSP, (ii) the LSP is considered older than another LSP previously stored for the second node, and (iii) the stored LSP fails authentication.

A first apparatus for handling Link State Packets (LSPs) sent between processing nodes within a computer network, comprising:

• means for at the first apparatus, receiving a first LSP sent by a second apparatus, wherein the LSP specifies connectivity information regarding the second apparatus;
• means for determining whether the first received LSP is an updated LSP even when the first received LSP has a lower sequence number than another LSP previously sent by the second apparatus to the first apparatus;
• and
• means for if it is determined that the first received LSP is an updated LSP, performing updating procedures on LSP information, that is maintained by the first node, based on the first received LSP, wherein the LSP information was obtained from one or more LSPs sent by the second node,
• updating the first node's routing tables based on the LSP information maintained by the first node after the updating procedures on the LSP information are performed;
• and
• means for sending a second LSP with an updated sequence number from the first apparatus back to the second apparatus if it is determined that the received LSP is an updated LSP.

A method for handling Link State Packets (LSPs) sent between processing nodes within a computer network, the method comprising:

• at a first node, receiving an LSP sent by a second node, wherein the LSP specifies connectivity information regarding the second node;
• if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, purging LSP information regarding the second node that is being maintained by the first node;
• and
• if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, flooding a second LSP from the first node to the first node's neighbor nodes, wherein the second LSP is structured to cause a purging of LSP information regarding the second node that is being maintained by the neighbor nodes,
• wherein the LSP information is purged and the second LSP is flooded to the first node neighbor nodes only if one or more purging conditions are met that minimize an intruder from isolating the second node from the network.

A first apparatus operable to handle Link State Packets (LSPs) sent between processing nodes within a computer network, the apparatus comprising:

• one or more processors;
• one or more memory, wherein at least one of the processors and memory are adapted for:
• at the first apparatus, receiving an LSP sent by a second apparatus, wherein the LSP specifies connectivity information regarding the second apparatus;
• if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, purging LSP information regarding the second apparatus that is being maintained by the first apparatus;
• and
• if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, flooding a second LSP from the first apparatus to the first apparatus' neighbor apparatus, wherein the second LSP is structured to cause a purging of LSP information regarding the second apparatus that is being maintained by the neighbor apparatus,
• wherein the LSP information is purged and the second LSP is flooded to the first node neighbor nodes only if one or more purging conditions are met that minimize an intruder from isolating the second node from the network.

At least one computer readable storage medium having computer program instructions stored thereon that are arranged to perform the following operations:

• at a first node, receiving an LSP sent by a second node, wherein the LSP specifies connectivity information regarding the second node;
• if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, purging LSP information regarding the second node that is being maintained by the first node;
• and
• if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, flooding a second LSP from the first node to the first node's neighbor nodes, wherein the second LSP is structured to cause a purging of LSP information regarding the second node that is being maintained by the neighbor nodes,
• wherein the LSP information is purged and the second LSP is flooded to the first node neighbor nodes only if one or more purging conditions are met that minimize an intruder from isolating the second node from the network.

A first apparatus operable to handle Link State Packets (LSPs) sent between processing nodes within a computer network, the first apparatus comprising:

• at the first apparatus, means for receiving an LSP sent by a second apparatus, wherein the LSP specifies connectivity information regarding the second apparatus;
• means for purging LSP information regarding the second apparatus that is being maintained by the first apparatus if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node;
• and
• means for flooding a second LSP from the first apparatus to the first apparatus' neighbor apparatus if the received LSP fails authentication and the received LSP is considered newer than a stored LSP that was last previously stored for the second node by the first node, wherein the second LSP is structured to cause a purging of LSP information regarding the second apparatus that is being maintained by the neighbor apparatus,
• wherein the LSP information is purged and the second LSP is flooded to the first node neighbor nodes only if one or more purging conditions are met that minimize an intruder from isolating the second node from the network.