Fast Ethernet
11-3
Q
10/100 Mbps transmission speed
These capabilities differ between the Tx and Fx port types. They are
presented in the following table and discussed in the paragraphs below.
Auto-negotiation
The 7600 Card has the capability of negotiating with the device with
which it is to communicate prior to data transfer in order to determine its
mode and speed capabilities (
auto-negotiation
). The 7600 Card then
automatically adjusts its data transmission mode and speed to match that
of the communicating device as detailed in the next two sections.
Auto-negotiation is set for each port separately and may be set
individually for either transmission mode or speed. If auto-negotiation is
not specified, the parameter must be set manually. The auto-negotiation
capability is available for Tx ports (copper) only.
Full or Half Duplex Mode
Fast Ethernet as implemented in the 7600 Card can communicate in
either full or half duplex mode, for both Tx and Fx port types. The
duplex auto-negotiation capability is available for Tx ports only. The Fx
ports must be set manually to either full or half duplex. When duplex
auto-negotiation is selected, the mode in which the 7600 Card chooses to
operate is determined by the communication modes available in the
device with which it is communicating. If the device with which it is
communicating also has a full-duplex mode (such as another 7600 Card),
then it communicates in full-duplex, otherwise it communicates in
half-duplex.
Table 11-1 Fast Ethernet Port Capabilities
Port type
Capability Tx Port Fx Port
Auto-negotiation
yes no
Full/half duplex
yes yes
10/100 Mbps
yes no (100 Mbps
only)
abtthgde.book Page 3 Tuesday, June 23, 1998 10:29 AM
