Allied Telesis AT-CV5000- Network Card User Manual


 
AT-CV5000 Media Converter Chassis Installation Guide
35
with an end node, the end node should also be using Auto-Negotiation.
Otherwise, a duplex mode mismatch can occur. A line card port, using
Auto-Negotiation, defaults to half-duplex if it detects that the end node is
not using Auto-Negotiation. This results in a mismatch if the end node is
operating at a fixed duplex mode of full-duplex.
Consequently, when you connect an end node with a fixed duplex mode of
full-duplex to a line card port, you should use the AT-S70 management
software to disable Auto-Negotiation on the port and set the port speed
and duplex mode manually.
Store-and-
Forward
The bridging media converter line cards, for example the AT-CM202,
AT-CM2K0S, and CM212x/1 Series line cards, use store-and-forward as
the method for receiving and transmitting frames. When an Ethernet frame
is received on a line card port, the line card does not retransmit the frame
out the destination port until it has received the entire frame and has
stored the frame in a port buffer. It then examines the frame to determine if
it is a valid frame. The line card discards invalid frames, such as fragments
or runts. This ensures that only valid frames are transmitted out the line
card ports and that damaged frames are not propagated on your network.
Pass-through The non-bridging media converter line cards, for example the AT-CV102
and AT-CV1KSS, use pass-through as the method for receiving and
transmitting frames. The line cards can support any frame size. They only
support one speed on the copper and fiber ports. These line cards do not
support the filtering feature and do not learn any MAC addresses.