Velocity Reviews > Router interface utilization

# Router interface utilization

terrydoc@o2.ie
Guest
Posts: n/a

 06-12-2008
Hi, how do you calculate the interface utilization -
utilization on the interface is (222/255) 88%

Trendkill
Guest
Posts: n/a

 06-12-2008
On Jun 12, 7:25 am, "(E-Mail Removed)" <(E-Mail Removed)> wrote:
> Hi, how do you calculate the interface utilization -
> total the 100 (txload) and 122(rxload), get 222 and say the
> utilization on the interface is (222/255) 88%

No, the transmit and receive are mutually exclusive. tx is transmit,
rx is receive, and therefore you treat them differently. I suppose
you could aggregate them and then take it over 510, but I can't think
of any real reason to look at it that way. Additionally, the tx/rx
are averaged over a set amount of time if I recall correctly, like 5
minutes, but its using some specific calculation. Since bandwidth on
circuits is full duplex (1.5 meg transmit AND 1.5 meg receive on a T1
for example), you do not aggregate tx and rx.

http://www.staticnat.com/WP/2007/03/...t-really-mean/

http://www.cisco.com/en/US/docs/ios/.../int_s3gt.html

Trendkill
Guest
Posts: n/a

 06-12-2008
On Jun 12, 7:35 am, Trendkill <(E-Mail Removed)> wrote:
> On Jun 12, 7:25 am, "(E-Mail Removed)" <(E-Mail Removed)> wrote:
>
> > Hi, how do you calculate the interface utilization -
> > e.g. reliability 255/255, txload 100/255, rxload 122/255 - do you
> > total the 100 (txload) and 122(rxload), get 222 and say the
> > utilization on the interface is (222/255) 88%

>
> No, the transmit and receive are mutually exclusive. tx is transmit,
> rx is receive, and therefore you treat them differently. I suppose
> you could aggregate them and then take it over 510, but I can't think
> of any real reason to look at it that way. Additionally, the tx/rx
> are averaged over a set amount of time if I recall correctly, like 5
> minutes, but its using some specific calculation. Since bandwidth on
> circuits is full duplex (1.5 meg transmit AND 1.5 meg receive on a T1
> for example), you do not aggregate tx and rx.
>
>
> http://www.cisco.com/en/US/docs/ios/.../reference/int...

So using your numbers, transmit is 100/255 or 39.2% utilized, and
receive is 122/255 or 47.8% utilization.