Patent ID: 11936490
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 1:
2. The first L2 switch according to claim 1, further comprising:
a failure determining unit, including the one or more computing devices, configured to determine whether or not a failure has occurred in the second L2 switch,
wherein, in a case in which the failure determining unit determines that the failure has occurred in the second L2 switch:
the apparatus specifying unit is configured to specify a second network apparatus serving as a second transmission source of the upstream communication, and
the session information processing unit is configured to:
specify (i) a second port of the first L2 switch connected to the second specified network apparatus serving as the second transmission source of the upstream communication and (ii) a second MAC address of the second transmission source of the upstream communication connected via the second specified port, and
store, in the storage unit, session information of the upstream communication in which information regarding the second specified port and the second specified MAC address is associated with header information set for the copy of the upstream communication.