# US 8,543,678 B2 · Synchronization method for NAT static port forwarding objects in redundant configurations > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,543,678 B2 - Document ID: US8543678B2 - Status: Granted - Kind: B2 - Application number: 13/342,728 - Filed: 2012-01-03 - Published: 2013-07-04 - Granted: 2013-09-24 - Earliest claimed: 2012-01-03 - Assignees: Alcatel Lucent - Applicants: Loredana M. Nitu; Anand Thiagarajan; Gurudas Somadder; Zihuang Wang; Attaullah Zabihi-Seissan - Inventors: Loredana M. Nitu; Anand Thiagarajan; Gurudas Somadder; Zihuang Wang; Attaullah Zabihi-Seissan - Web page: https://patentgrep.com/patent/US8543678B2 ## CPC - H04L 61/2514: between local and global IP addresses - H04L 41/0806: for initial configuration or provisioning, e.g. plug-and-play - H04L 61/2557: Translation policies or rules - H04L 41/0668: by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure - H04L 67/1095: Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract The invention is directed to providing a centralized synchronization method for redundant network elements and is particularly advantageous to routers providing network address translation (NAT) services requiring static port forwarding provisioning. Synchronization is provided by a network management system which can handle one or more backup routers or other network elements using a control protocol different from the control protocol used by the active router. ## Claims ### Claim 1 A method performed by a network management system for synchronizing an active network element and one or more standby network elements, the method comprising steps of: Sending to said active network element a provisioning request for a static mapping for a target address; Receiving from said active network element a current list of mappings corresponding to said target address; Updating a management system database with said current list of mappings corresponding to said target address; and Sending to said one or more standby network elements, a provisioning command for said static mapping for said target address. ### Claim 2 (depends on 1) The method of claim 1, further comprising between said step of sending to said active network element a provisioning request and said step of receiving from said network management database a list of mappings, steps of: Receiving from said active network element a success/fail response; and Responsive to receiving said success response, sending a query to said active network element for mappings corresponding to said target address. ### Claim 3 (depends on 1) The method of claim 1, wherein said step of updating a management system database comprising steps of: Sending a query to said network management database for mappings corresponding to said target address; Receiving from said network management database a list of mappings corresponding to said target address; Determining a difference between said current list of mappings from said active network element to said list of mappings from said network management database; and Sending an update to said management system database of said difference. ### Claim 4 (depends on 1) The method of claim 1, wherein said network elements comprise routers supporting network address translation (NAT). ### Claim 5 (depends on 1) The method of claim 1, wherein said target address comprises an internal Internet Protocol (IP) address. ### Claim 6 (depends on 5) The method of claim 5 wherein said target address further comprises a port number. ### Claim 7 (depends on 1) The method of claim 1 wherein said network management system communicates with each said network element using a communication protocol selected from the set of: Simple Network Management Protocol (SNMP); Command Line interface (CLI); and Network Configuration Protocol (NETCONF). ### Claim 8 (depends on 7) The method of claim 7 wherein at least one of said network elements is from a different vendor than the other of said network elements. ### Claim 9 (depends on 1) The method of claim 1 wherein said provisioning request comprises a specific IP address mapping for said target address. ### Claim 10 (depends on 1) The method of claim 1 wherein said provisioning request is selected from the set of: creating a new mapping; modifying an existing mapping; and deleting an existing mapping. ### Claim 11 (depends on 1) The method of claim 1 preceded by a step of receiving said provisioning request from a network operator via an Operation Support Services (OSS) Interface. ### Claim 12 A tangible and non-transitory machine-readable storage medium encoded with instructions for execution by a network management system for synchronizing an active network element and one or more standby network elements, the tangible and non-transitory machine-readable storage medium comprising: instructions for sending to said active network element a provisioning request for a static mapping for a target address; instructions for receiving from said active network element a current list of mappings corresponding to said target address; instructions for sending a query to a network management database for mappings corresponding to said target address; instructions for receiving from said network management database a list of mappings corresponding to said target address; instructions for determining a difference between said current list of mappings from said active network element to said list of mappings from said network management database; instructions for sending an update to said management system database of said difference; and instructions for sending to said one or more standby network elements, a provisioning command for said static mapping for said target address.