Abstract: When receiving a session control signal from a terminal (12), a terminal accommodating apparatus (11) disposed for each line adds the identifier of an access line to the received session control signal and then transmits the resultant signal to a session control server (3). The session control server (3) transmits the access line identifier to a QoS control server (5). The QoS control server (5) performs a QoS control based on a band requested in the session associated with the identifier of the same access line.

Abstract: Even if a mistaken reply to a host name resolution request of IPv6 is issued by a DNS contents server, a requesting terminal can still acquire an IPv4 address. When a host name resolution request of IPv6 (AAAA query) is received, a DNS proxy server generates a host name resolution request of IPv4 having an identical domain name, transmits this together with the AAAA query to the DNS contents server, and determines the DNS reply which should be returned to the terminal from the contents of the DNS reply of IPv6 (AAAA reply) and the DNS reply (A reply) of IPv4 received from the DNS contents server. Hence, even if a reply message showing a domain name error is received from the DNS contents server, if the A reply is correct, the DNS proxy server generates an AAAA reply showing that the desired address does not exist, and returns this to the terminal.