Abstract: A server, which has a GRE tunnel function, includes a selecting means to select any one of a layer 3 transferring method and a layer 2 transferring method, which designates a direct interface to carry out transferring, as a transferring method in the case that GRE tunnel encapsulation is carried out, and to select said layer 2 transferring method if both said transferring methods are available.

Abstract: A rotating type developing apparatus, having a plurality of developing devices which convey developer, which at least includes toner and carrier, to a developing roll while accommodating and circulating the developer; and a rotating body which holds and rotates the plurality of developing devices, in a rotating type developing apparatus in which the plurality of developing devices successively oppose a photosensitive drum due to the rotation of the rotating body so as to form a multicolor image, the apparatus having developer supplying equipment which supplies the developer to the developing devices; and collecting equipment which collects excess developer within the developing devices due to the rotation of the rotating body.