COMMUNICATION SYSTEM AND COMMUNICATION METHOD

摘要

PROBLEM TO BE SOLVED: To enhance flexibility of communication to be performed among different networks since firewall access is typically limited to communication including electronic mails and web communication in a communication system having a firewall device. SOLUTION: The communication system negotiates one of plural formats to establish data connection among a transfer medium to transfer data, the firewall device and communication equipment and to transfer the data. Data transfer is executed by formatting the data to be transmitted corresponding to negotiation.