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New Member

Help wih Interface throughput.

I'm looking at the serial interface on a 1751 router that has a single Frame relay PVC running on it and it shows the following throughput. (It has a 48K CIR and a 64K access speed.The serial interface has the bandwidth 64 command implemented.)

Available Bandwidth 48 kilobits/sec

5 minute input rate 29000 bits/sec, 37 packets/sec

5 minute output rate 25000 bits/sec, 40 packets/sec

Why does the available bandwidth only display 48/kilobits a second when i would have thought it should be 64 ?

Also if we're tranmitting below the Access rate but above the available bandwidth will this lead to dropped packets/latency ? (assuming in this case that the FR network isn't congested)

Is there any way of showing over time how much of a workout the output queue's are getting ?

I am trying to prove that some of our sites need higher bandwidth however this is hard to prove because the people that monitor our network are only getting alarms when the line is over-utilised for 10 minutes or so. Obviously with Citrix traffic latency is a big problem and people tend to notice on a minute by minute basis how slow things are going. I know for a fact that were are getting output drops on the interface but what can be considered acceptable ?

Output queue: 0/1000/64/39 (size/max total/threshold/drops)

Last clearing of "show interface" counters 00:34:20



Accepted Solutions

Re: Help wih Interface throughput.

64Kbps combined input and output.

New Member

Re: Help wih Interface throughput.


When you are given CIR, that's your real BW. Access rate is 64 only means you are able to burst into 64 when you have enough credit.

Bandwidth statement under the serial interface has nothing to do with the access rate. it's the configuration used for routing metrics.

If you always have output drop on the interface. that means your output traffic is exceeding the CIR.



New Member

Re: Help wih Interface throughput.

When we have service that has a 64k CIR does that mean 64k/sec input and output or is that 64k total of the input and output.


Re: Help wih Interface throughput.

64Kbps combined input and output.

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