Network monitoring device

A monitoring device for monitoring a network to which a plurality of transmission devices are connected, said monitoring device comprising:

• a data storage unit which stores status information of all of said transmission devices;
• an information attaching unit which attaches abridged status information of at least one of said transmission devices to a polling command, sends said polling command to said at least one of said transmission devices, and updates said status information based on a report sent from at least one of said transmission devices, wherein said abridged status information is generated to reflect said status information so that said at least one of said transmission devices can incorporate into said report information needed to update said status information,
• wherein said at least one of said transmission devices also checks to see if there is a mismatch between said abridged status information and second status information.

A transmission device connected to a network and monitored by a monitoring device which keeps first status information of said transmission device, said transmission device comprising:

• a data storage unit which stores second status information of said transmission device;
• a management unit which receives abridged status information of said transmission device attached to a polling command sent from said monitoring device, said abridged status information reflecting said first status information;
• a comparison unit which checks if there is a mismatch between said abridged status information and said second status information.