3Com 3C16792 User Guide - Page 7

Hub Connections Depending on what ports your hub has, you can use either 10BASE-T or 10BASE-2 to connect your hubs together: s With 10BASE-2 you can connect up to 30 hubs on a single segment, leaving all of the 10BASE-T ports free. s With 10BASE-T you can connect up to four hubs in series. 10BASE-2 To connect additional hubs using 10BASE-2 (Hub 4C and 8C only), you need (as shown in Figure 2): s One 10BASE-2 50 Ohm cable for each additional hub. The minimum cable length you can use is 0.5m (1.6ft). The maximum segment length is 185m (607ft). s One 10BASE-2 'Y' piece for each hub. You can use 'T' pieces but 'Y' pieces provide optimal clearance of the other ports. s Two 10BASE-2 50 Ohm terminators (end pieces). Figure 2 Some of the 10BASE-2 Equipment You May Need 10BASE-T If you have additional hubs you want to connect using 10BASE-T, you need: s One straight-through TP cable for each extra hub. Twisted Pair (TP) Cables To connect your workstations and hubs, you must use straight-through TP cable with RJ-45 connectors. Cables can be shielded (screened) or unshielded; we recommend that you use shielded. The maximum length you can use is 100m (328ft). A straight-through cable is one where the pins of one connector are connected to the same pins of the other connector. Terminator (end piece) or 'Y' piece 'T' piece 7