Cabletron Systems Netlink FRX4000, User Manual

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7-8 FRX4000/FRX6000 4.0 User Guide, Rev 01
both groups are assigned to IP interfaces. Under a full traffic load, Group 1 will be
allocated 60/130 (46%) of the available bandwidth, and Group 2 will be allocated 70/
130 (54%).
Group "n" Excess Priority
determines the order in which groups are given their allocations of bandwidth; the
higher the number, the higher the priority.
Group "n" Use Excess Burst
will (if
Y
) allow traffic that falls into the Excess Burst Size to be transmitted. Any
packets exceeding B
E
will be buffered in the FRX4000/6000.
Configuration Example
Here is an example of a typical Bandwidth Allocation Group configuration:
This configuration ensures that SNA traffic, which is very time-sensitive, will be
given top priority, and will all be transmitted within the guaranteed 30% of the band-
width, eliminating the risk of discarded packets. Sequenced arrival of packets is not
critical among the first three groups, so those types of traffic can be configured to
allow transmission above the
Committed Information Rate (CIR). (Traffic above CIR
is transmitted with the Discard Eligibility bit set, which allows packets to be discarded
if necessary.)
Table 7-2 Bandwidth Allocation Example
Group Used For Percentage Excess Priority Use Excess Burst
1
SNA
30 16 N
2
Logical Ports & Mgmt.
20 15 Y
3
IP
30 14 Y
4
IPX
20 13 Y