ASR Throughput

[soztekin@hotmail.com]

Hello all

We have Cisco 4331 routers . By default i know that without performance license its throughput limit is 100 Mbit/ps .

i have inteface  ( Wan and Lan ) traffic rates like ;

Gig 0/0/1 ( Wan Interface ) 

30 second input rate 53375000 bits/sec, 7582 packets/sec
30 second output rate 18681000 bits/sec, 5947 packets/sec

Gig 0/0/0 ( Lan Interface ) 

30 second input rate 16602000 bits/sec, 6847 packets/sec
30 second output rate 54694000 bits/sec, 8119 packets/sec

So to define total throughput, am i supposed to sum all traffic rates ( 53375000 +18681000 + 16602000 + 54694000 ) or just ingress rates ( 53375000 + 16602000 ) ? Which traffic am i limited with 100 Mbit ? 

Thanks 

[Joseph W. Doherty]

I believe the performance limit is counted against all traffic crossing the "backplane".  I.e. you would count the sum of all interfaces' ingress OR all intefaces' egress, but not both.

However, what I don't is how the limit is applied when traffic is being dropped.  For example, is ingress traffic counted if dropped by an ingress ACL (doesn't cross the backplane) or conversely is egress traffic counted if dropped by an egress ACL (did cross the backplane)?

[soztekin@hotmail.com]

Thank you 

[pman · Accepted solution]

Hi,

I believe the following document will answer your question:

https://www.cisco.com/c/en/us/support/docs/routers/4000-series-integrated-services-routers/217135-performance-license-on-cisco-isr4000.html

Hope I helped.

[soztekin@hotmail.com]

Hi,

In the documantation it is written like that ; 

Tip: The licensed throughput is applicable to QFP Egress (outgoing traffic).
The Performance License congests the Data Plane external interface output when outgoing traffic exceeds the licensed throughput.
By default, the excess traffic is shaped. On other platforms, a policing-based option is available.

This is answer i think 

Thank you 

[Joseph W. Doherty]

Yes, that should be your answer.

BTW, I was surprised that the bandwidth cap is done using a shaper rather than a policer.  I was also surprised that you can adjust priorities between interfaces (or a least I recall seeing mention of that, but don't recall document showing exactly how to do it).

Also in answer to my questions about ACLs, ingress ACLs should keep its blocked traffic from adding to the bandwidth limit restriction, but conversely, egress dropping doesn't preclude that traffic from counting toward your bandwidth limit.

Why does this matter?  Because, for example, assume you have multiple ingress ports whose traffic exits on one egress port.  For ease of maintenance you support an egress ACL on the egress port, and not ingress ACLs on those multiple ingress ports.  Traffic being dropped using the egress ACL will still count toward your bandwidth cap but it wouldn't count if dropped on ingress ports.