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CFIP PhoeniX C Series TDM/IP Split Mount System Technical Description and Configuration Guide
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Rev. 1.0
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© SAF Tehnika JSC 2013
Figure 64: Advanced ETH settings
The description of particular setting and display boxes – OPTIONAL ETH
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Jumbo Frames Support –
these boxes make it possible to select what ports will support Jumbo
Frames (length up to 10 kB). There exist different Jumbo frames mode settings for the ETH switch
ports (LAN1 -3, WAN A-B) and the SFP ports. Because SFP ports are not connected into ETH
switch directly and different designs use specific SFP modes, the user himself has to decide about
the correct Jumbo frame configuration.
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In SINGLE design – Just Jumbo Frame setting for LAN and WAN port is important. The
setting of SFP boxes does not affect the proper ETH function.
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In MULTI design – All selection boxes have an influence on Jumbo Frames function.
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In PROTECTED design – Jumbo frames setting for port SFP 1 (protection port) does not
affect correct protection function.
NOTE:
Jumbo Frames Support reserves more space in ETH switch FIFO and especially in packet
processor FIFO. Therefore number of buffered packets is limited in this mode.
The description of particular setting and display boxes – QOS ETH
This section makes it possible to configure extended QOS modes which are important for a specific
traffic prioritization. The system uses four priority queues for each port where frames, with an
assigned initial frame priority, an initial queue priority and an override queue priority, are mapped
onto four output queues according to QPRI settings. A final frame queue priority is derived from the
assigned initial queue or the override queue priority and it is used for deciding what queue will be used
for frame buffering. The queue with a higher number is egressed with higher priority than the queues
with lower numbers. The assigned initial frame priority is then used for replacing of frame's PRI bits in
802.3ac VLAN tag section, when the frame is egress tagged.