Connection adapter for communication device

A connection adapter for connecting a communication device for use in a radio packet communication network and high-level equipment which performs communication utilizing TCP/IP by using said communication device, comprising:

• a connection controller which controls a connection between said high-level equipment and said radio packet communication network;
• and
• a communication controller which relays communication by said high-level equipment using said communication device;
• wherein:
• when said communication controller detects duplication of a TCP packet which the high-level equipment sent to said radio packet communication network, said communication controller discards the duplicated TCP packet.