LevelOne WBR-3470, Руководство пользователя

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we want to only allow 20% of the total data transfer rate for the LAN-to-WAN direction to be
used for FTP server. Then we can specify here with data ratio = 20. If you have ADSL LINE
with 256K/bps.rate, the estimated data rate, in kbps, for this rule is 20%*256*0.9 = 46kbps.
(For 0.9 is an estimated factor for the effective data transfer rate for a ADSL LINE from LAN
to WAN. For WAN-to-LAN, it is 0.85 to 0.8).
Data Ratio : percentage for the data rate to be controlled by this policy. As above FTP
server examples, it is 20.
Rate Type : We provide 2 types here:.
~ Fixed (Maximum): specify a fixed data rate for this policy. It also is the maximal rate for
this policy. As above FTP server example, you may want to “throttle” the outgoing FTP
speed to 20% of 256K and limit to it, you may use this type.
~ Guaranteed (Minimum): specify a minimal data rate for this policy. For example, you
want to provide a guaranteed data rate for your outside customers to access your internal
FTP server with, say at least, 20% of your total bandwidth. You can use this type. Then, if
there is available bandwidth that is not used, it will be given to this policy by following priority
assignment.
Priority for Non-used Bandwidth: Specify the priority for the bandwidth that is not used.
For examples, you may specify two different QoS policies for different applications. Both
applications need a minimal bandwidth and need more bandwidth, beside the assigned one,
if there is any available/non-used one available. So, you may specify which application can
have higher priority to acquire the non-used bandwidth.
~ High
~ Normal : The default is normal priority.
~ Low
For the sample priority assignment for different policies, it is saved in a First-In-First-Out
way.
DSCP Marking : Differentiated Services Code Point (DSCP), it is the first 6 bits in the ToS
byte. DSCP Marking allows users to classify traffic based on DSCP value and send packets
to next Router.
DSCP Mapping Table
Disabled None
Best Effort Best Effort (000000)
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