3com 5500G-EI. Maximum data transfer rate: 1 Gbit/s, Supported data transfer rates: 107.1 Mpps forwarding rate, Switching capacity: 184 Gbit/s. Compatible operating systems: 3Com Operating System; shared with 3Com Switch 8800, 7700 and Router 6000. Data transfer rate: 136.9 Mbit/s, Dimensions (WxDxH): 440 x 450 x 43 mm, Networking features: DHCP tracker, UDP helper, traceroute, 1-1 traffic mirroring (standalone unit only)