PURPOSE: To reduce the address retrieval time in a connector with a high relay frequency of occurrence by varying an address retrieval time in response to the operating state of the connector.

CONSTITUTION: A measured relay rate storage area 6 stores a calculated relay rate based on processing frame information in a filtering processing section 8. A data base retrieval range decision section 7 decides the data retrieval range in the filtering processing section 8 based on the set relay rate and measured relay rate information stored in relay rate storage areas 5, 6. In such a case, when the measured relay rate is higher than the set relay rate, the address retrieval range from the filtering processing section 8 to an address data base for LAN A 3 or for LAN B 4 is increased, while lower, the address retrieval range is decreased. Thus, the measured relay rate is made close to the set relay rate and a proper filtering processing time in response to the operating state of a bridge is obtained.