72 Appendix A Technical specificationsNN46110-308 02.01System portsThe VPN Router 600 system board provides the following built-in interfaces:• 10/100BASE-TX Ethernet LAN ports• Serial portThis section provides information about the 10/100BASE-TX Ethernet LAN portsand the serial port on the system board.10/100BASE-TX Ethernet LAN portThe system board provides two 10/100BASE-TX Ethernet LAN interfaces on therear of the chassis. (LAN 0 is generally used for Web management, and LAN 1 isgenerally used as a public LAN.) These interfaces accommodate an RJ-45straight- through cable. Depending on whether you use the interface for10BASE-T or 100BASE-TX operation, select cables for the interface as follows:• 100BASE-TX connections require Category 5 twisted-pair wire. The100BASE-TX specification supports 100 Mb/s transmission over two pairs ofCategory 5 twisted-pair Ethernet wiring: one pair each for transmit andreceive operations.Nortel recommends a maximum length of 100 meters for the cable segmentbetween a 100BASE-TX repeater and a workstation (due to signal timingrequirements). This wiring scheme complies with the EIA 568 wiringstandard.• 10BASE-T connections can use Category 3, 4, or 5 twisted-pair wiring.Figure 20 on page 73 shows the 10/100BASE-TX Ethernet connector and itspinouts.
