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Weird Internet Bandwidth Graph Trend

Level 1
Level 1

Dear all,

We are peering to our ISP. We noticed from our monitoring tool, the bandwidth trend shows weird as it looks in "saw" shape.

Image as below:-

What we usually see suppose to be almost a straight line right?

Can anyone help to clarify what cause the saw shape?

FYI it is the bandwidth for incoming from our upstream provider.


5 Replies 5

Level 1
Level 1

Hi Mate,

I dont think you will see the straight line...The grapgh is showing the utilization of the link...and it almost going up and, This is common behaviour, by checking this graph you can see the utilization of the BW and if it reaching above or keeping low than contractual BW then u can ask the SP for further clarification.

As dont bother urself.



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Hi Thanks

Second things, the maximum bandwidth we purchased is 95Mbps for download and 25Mbps for upload.

But just wondering why there is spike on the bandwidth which exceeded above 95Mbps commonly.

Is it due to burst rate?

Please advise


Yes this is mostly happen due to intermittent burst..if QoS is configured then check the policy settings and drops it should be there if you r bursting the traffic..and even u can use the netflow or top-talkers to check , who is bursting heavy traffic over WAN...

Hope this would be helpful to u..

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Joseph W. Doherty
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Saw tooth can be very common when monitoring links with very few rate-adaptive flows that can exceed link bandwidth.

What happens, for example, a single rate-adaptive flow (e.g. FTP) "probes" available bandwidth by increasing its bandwidth utilization (the front side of the saw tooth).  When such a flow exceeds available bandwidth, it generally sees packet drops and backs-off its bandwidth demand (the back side of the saw tooth).  It continues to repeat this process.

Short lived rate-adaptive flows (e.g. HTTP) might also show a saw tooth as they increase their bandwidth usage but then finish their transmission.

Rate-adaptive flows that stop "probing" bandwidth before reaching link capacity, may show as square tooth.

Non-rate adaptive flows may show as irregular bandwidth usage if they are variable bit rate (e.g. video) but if constant bit rate (e.g. VoIP g.711) will show as a flat line.

Lastly, if you have a mix of traffic, graph can be very irregular as it shows the aggregation of all the concurrent data flows.

Level 1
Level 1

looks kind of normal, as the graph is at 5mins interval.

you may want to view daily or weekly graph, if available. you will be able to observe some pattern and trend of the network.

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