Appendix B: FE-100TX, FE-100FX, and FE-100F3 Specifications
B-2 2E48-27R/2E49-27R User’s Guide
B.1.1 Auto-Negotiation
When using the optional FE-100TX Fast Ethernet Interface Modules,
these twisted pair ports have the ability to auto-negotiate the type of
connection required to provide a link to another device. During
Auto-Negotiation, two devices automatically exchange information
“telling” each other what their operating capabilities are. The
Auto-Negotiation feature targets the maximum capabilities that can be
reached between the two devices. For example, the Interface Module port
adjusts to 100 Mbps when the device on the other end of the connection
can also adjust between 10 Mbps or 100 Mbps. If the device on the other
end of the connection can only operate at 10 Mbps, then the port simply
adjusts to 10 Mbps operation.
When Auto-Negotiation is supported at both ends of a link, the two
devices dynamically adjust to full or half duplex operation based on the
maximum capability that can be reached between the two devices. If the
device connected to the 2E4X-27R cannot auto-negotiate, the 2E4X-27R
interface operates according to the capabilities of the other device.