CTC Union FTH4-1000MS, Руководство пользователя

Страница: 24 / 47

24
This converter is capable of supporting
Jumbo Frames (9k byte packets) when this option is enabled. Note that in order to support jumbo
frames, the TP speed and duplex must match the FX. Jumbo Frames are not typically used on a normal network, since most devices are not
able to handle them and they would be truncated. Most PCs, servers, switches, DSL and WiFi do not support jumbo frames. Jumbo frames
can only work on a pure Jumbo frame network, which currently only exists in data centers for server-to-server or server-to-storage connections
and on some education back bone networks. Jumbo frames will always be considered to be illegal, non-standard Ethernet packets, according
to IEEE802.3. In most cases, the call for jumbo frame support is just marketing hype.
Link Loss Carry Forward or Link Fault Pass through ( LFP ) allows a link condition to be passed from fiber to TP or from TP to fiber. This
function is disabled by default.
Auto Laser Shutdown (ALS) is an optical safety mechanism which will shutoff laser transmission if the transceiver experiences a loss of
receive signal. This function is disabled by default.
Forward CRC Frame option is disabled by default. The normal behavior of a switch is to read the entire Ethernet frame (store), calculate
the checksum and compare to the FCS in the packet. If the checksum matches, the packet is transmitted (& forwarded). If the checksum does
not match, the switch considers the packet to have CRC error and drops it. If this option is enabled, the packet with CRC error will still be
forwarded instead of being dropped.
The option
Forward Pause Frame allows pause frame forwarding to occur when enabled. Pause frames are special broadcast frames
defined in IEEE802.3X. Normally pause frames are used by the switch to throttle packets through a bottle neck rather than drop excess
packets (for example, if
1000M data stream is exiting a lower speed 100M port). Normally, the pause frames are not forwarded between
interfaces in the switch. In many cases, pause frames are considered problematic. Therefore, their forwarding is disabled by default in this
converter.