Allocating internet protocol (ip) addresses to nodes in communications networks which use integrated is-is

Abstract

Previously it has only been possible to allocate unique internet protocol (IP) addresses to nodes in open systems interconnection (OSI) communications networks such as those using integrated IS-IS, by manual configuration. This is time consuming and expensive because an operator must travel to the site of the node. By exploiting features of the OSI routing protocol the present invention enables IP addresses to be automatically allocated to the new network nodes. This is particularly advantageous for new intermediate systems such as optical multiplexers with integral routers. Once an IP address has been allocated, the node can be managed by a remote management system or operator using internet protocol methods.

1 . A method of automatically allocating an internet protocol (IP) address in a communications network, the method comprising:
 maintaining information about a plurality of available IP addresses;   allocating one of the plurality of available IP addresses to a node of the communications network, the allocated one of the plurality of available IP addresses being a unique IP address to be used for accessing the node of the communications network;   informing the node of the communications network of the unique IP address; and   accessing, by an IP management system, the node of the communications network using the unique IP address.   
     
     
         2 . The method of  claim 1 , wherein informing the node of the communications network of the unique IP address comprises sending information about the unique IP address to the node in link state protocol data units. 
     
     
         3 . The method of  claim 2 , wherein sending information about the unique IP address to the node in link state protocol data units comprises sending the information in link state protocol data unit extensions. 
     
     
         4 . The method of  claim 2 , wherein sending information about the unique IP address to the node in link state protocol data units comprises sending the information in link state protocol data units with anomalous sequence numbers. 
     
     
         5 . The method of  claim 1 , wherein the node of the communications network has no assigned IP address until the node is informed of the unique IP address allocated to the node. 
     
     
         6 . The method of  claim 1 , comprising determining that the node has been logically added to the communications network when the node has been informed of the unique IP address allocated to the node. 
     
     
         7 . The method of  claim 1 , wherein maintaining the information about the plurality of available IP addresses comprises maintaining the information about the plurality of available IP addresses at a server connected to the communications network. 
     
     
         8 . The method of  claim 1 , wherein maintaining the information about the plurality of available IP addresses comprises maintaining the information about the plurality of available IP addresses at the node the communications network. 
     
     
         9 . The method of  claim 1 , comprising changing the IP address allocated to the node of the communications network using the IP management system. 
     
     
         10 . The method of  claim 1 , wherein the communications network is an open systems interconnection (OSI) communications network. 
     
     
         11 . The method of  claim 10 , wherein the OSI network is an integrated intermediate-system-to-intermediate-system (IS-IS) communications network. 
     
     
         12 . The method of  claim 10 , wherein the integrated IS-IS communications network is configured to use IS-IS routing protocol. 
     
     
         13 . The method of  claim 1 , wherein the node of the communications network comprises an intermediate system. 
     
     
         14 . The method of  claim 1 , wherein the node of the communications network comprises a router. 
     
     
         15 . The method of  claim 1 , wherein the node of the communications network comprises an optical multiplexer with an integral router.