From: Sam Li (sxl099@xxxxxxxxxxx)
Date: Fri Jun 30 2000 - 17:03:35 GMT-3
I am puzzled on traffic shaping. I don't have problem on what commands to
use. I just could not figure out where do you get all parameters used in the
command.
I tracked back the archive of the mailing list, i.e. at
http://www.groupstudy.com/archives/ccielab/200005/msg00050.html
I think the parameters posted at fatkid.com
("traffic-shape group 101 16000 32000 32000 1000")
are ok to serve the purpose although it is confusing because of the same
number as 32kbps and not good because of using two second as the interval.
I would use
traffic-shape group 101 16000 2000 2000 which is 1/8 second as the interval.
In the same email mentioned the some helpful info on CCO, what is the url?
I check on the cisco manuals for better answer. Here is what I find.
*****************12.0 manual *************************
at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/qos_c/qc
part4/qcgts.pdf
QC-101 to 102
It states
Constrained Access Rate Example
In this example, a customer may use all of a T1 line for 30 seconds in a
burst, but the long-term average is limited to 64 kbps. This configuration
restricts the amount of load the system can induce on the outbound network
interface.
interface <his interface or sub-interface>
traffic-shape rate 64000 8000 46080000
If you need to restrict the amount of load the system can induce both
outbound and inbound, and therefore the total load it can induce on the
Internet Service Provider (ISP), configure traffic shaping on both the
inbound and outbound interfaces, as in the following example:
interface <serial interface or sub-interface>
traffic-shape rate 64000 8000 46320000
interface <LAN interface>
traffic-shape rate 64000 8000 46320000
****************** 12.1 Manual *****************
at
http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/qos_c/q
cprt4/qcdgts.pdf
page QC-135
Constrained Access Rate Example
In this example, a T1 line may be used for 100 milliseconds in a burst, but
the long-term average is limited to 64 kbps. This configuration example
restricts the amount of load the system can induce on the outbound network
interface.
interface serial 4/1:0
traffic-shape rate 64000 6400 6400
If you need to restrict the amount of load the system can induce outbound,
and therefore the total load it can impose on the Internet service provider
(ISP), configure traffic shaping on the outbound interfaces.
**********
I think the parameters used in 12.0 manual were wrong and in 12.1 were
correct. I think on 12.0 manual it should be
interface <his interface or sub-interface>
traffic-shape rate 64000 8000 440000 but that has nothing to with "30
second".
44000=1544000/8-8000
I especially don't understand how do they get the parameters for the ISP
example in 12.0 manual showed above.
Maybe that is why they don't use that example in 12.1 manual any more.
Could someone explain what do I miss?
If the lab ask you to "a customer may use all of a T1 line for 30 seconds in
a burst, but the long-term average is limited to 64 kbps"
What interval you are going to use? how does the "30 seconds" get into the
calculation?
How sorry it will be if you know all commands but can't figure out the
numbers to fill in!
Thanks in advanced,
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