Access control apparatus and access control method

A storage access control apparatus connected via one or a plurality of communication networks to a plurality of upper grade apparatuses, comprising:

• a channel adaptor equipped with an iSCSI port for receiving an access request issued from the upper grade apparatuses via said one or a plurality of communication networks, and one or a plurality of channel processors executing a process operation with respect to information outputted from said iSCSI port;
• one or a plurality of memories for storing thereinto plural sorts of permission access types which individually correspond to plural sorts of target network attributes which belong to a target communication network to which at least one of said upper grade apparatuses is connected, said attributes including a network logical distance;
• and
• a data storage apparatus for storing thereinto write data received from said at least one of the upper grade apparatuses and/or read data transmitted to said at least one of the upper grade apparatuses,
• wherein said one or plural memories store thereinto a plurality of iSCSI names corresponding to the upper grade apparatuses respectively, and
• said channel adaptor receives an access request, an iSCSI name, and a IP address from said at least one of the upper grade apparatuses via said one or a plurality of communication networks, (1) if the iSCSI name is not already stored in the one or plural memories, denies a request to access said at least one of the upper grade apparatuses;
• (2) if the iSCSI name is already stored in the one or plural memories, judges an attribute of said target communication network based upon said received IP address, identifies a permission access type corresponding to said judged attribute of the target communication network with reference to information stored in said one or a plurality of memories, and then permits according to said identified permission access type the request to access said data storage apparatus issued from said at least one of the upper grade apparatuses.