Patent ID: 9680741
Date: 2017-06-13
CPC Classifications: H04L

Claim:
1. A method of operating a switch or an access node in a network, the switch or access node having a plurality of interfaces through which data packets can be received and forwarded, the network further comprising one or more gateway nodes and one or more user terminals, each of the gateway nodes and the user terminals having a respective address, the method in the switch or access node comprising: learning the address for at least one of the gateway nodes, wherein learning comprises: comparing a second source address specified in a second data packet received from a user terminal at one of the interfaces of the switch or access node to the table of learned source addresses for the one or more gateway nodes; storing the second source address specified in the second data packet and the identity of the interface through which the second data packet was received if the second source address specified in the second data packet does not match the source addresses in the table of learned source addresses for any of the at least one of the gateway nodes; and discarding the second data packet if the second source address specified in the second data packet matches a source address in the table of learned source addresses for any of the at least one of the gateway nodes.