AT-FS709FC Series Installation Guide
10/100 Mbps Twisted Pair Ports
The twisted pair ports on the switch are labelled 1X through 7X, 8MDI-X and 8MDI. The features of the twisted pair ports are explained in the following sections.
Type of Connector
The twisted pair ports have RJ-45 connectors.
Speed
These ports are compliant with the 10Base-T and 100Base-TX standards and are capable of either 10 Mbps or 100 Mbps operation. The ports are IEEE 802.3u Auto-negotiation-compliant, meaning the speed for each port is set automatically by the switch after determining the speed of the end node connected to the port. Auto-negotiation is designed to ensure that each port on the switch and each end node are operating at the same speed and that they are communicating at the highest possible common speed of the devices.
Duplex Mode
The twisted pair ports can operate in either half- or full-duplex operation. Just as with speed, the ports use Auto-negotiation to set the duplex mode. If the end node is capable of full-duplex mode, the port is set to full-duplex. If the end node is capable of only half-duplex, the port is set to half-duplex. For an explanation of duplex mode, refer to the section “Duplex Mode” on page 8.
Cabling
The RJ-45 ports on the switch can use shielded or unshielded twisted pair cable. The categories of twisted pair cabling used in Ethernet networks are Category 3, 4, and 5. The main difference between the categories relates to their attenuation, which is a measurement of signal loss over the length of the cable. All cables experience attenuation, where the signal loses strength the longer the cable. The lower the loss of signal, the lower the attenuation.
Of the three categories, Category 3 has the highest attenuation, meaning that it has the highest signal loss. It is adequate for 10 Mbps operation, but should never be used for 100 Mbps network operations. The higher speed requires Category 5. If you are installing a new network with end nodes operating at 10 Mbps, it is recommended that you install Category 5 instead of Category 3. This will save you the trouble of having to install new twisted pair cabling should you later upgrade your end nodes to 100 Mbps.
