The GigaStack GBIC is an adapter that can only be installed into the GBIC modules slot of any supported switch. The maximum distance for a GBIC-to-GBIC connection is one meter. The GigaStack GBIC requires Cisco proprietary signaling and cabling. Each GigaStack GBIC consists of two ports, port 1 and port 2. One or both ports can be used, depending on cabling configuration.