akamai abnormal spike

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1

Good afternoon,

Has anyone notice any abnormal spike in Akamai trafic in the last 24-48
hours compared to other days. I know it was black tuesday yesterday but
traffic from last month didn't even come close to what we saw from Akamai.

We have some caching servers and even notice a spike to them as well.

Limelight even showed up on our network.

thanks
eric

2

We noticed on the 12th and 13th there was a significant up tick in traffic served from our Akamai servers as well.

3

We noticed that on the 12th-14th we had multiple subscribers on ~5Mbps subscription rates that were being sent ~50Mbps of data sourced from TCP port 80 (apparently HTTP) from Limelight Networks' servers. The data did appear to be user requested, still not sure why TCP didn't throttle the data rate appropriately. The 50Mbps was distributed across multiple LLNW servers. Makes me wonder if the customer was requesting one batch of data and multiple servers were responding.

The issue cleared up on its own and I never was able to perform a full packet capture to investigate. I have not noticed the same behavior from Akamai servers.

4

Several of my WISP colleagues have noticed this behavior (CDN sending way more traffic than the customer's pipe can handle) from (I believe) multiple CDNs. Not sure if it is intention on behalf of the CDN or an error, but it has been on-going for several months if not years.

5

Hi Eric,

There were two major software updates that spanned Tuesday and
Wednesday which are responsible for the increase you saw.

Best,

Martin Hannigan / AS 20940 / AS 32787

6

Several of my WISP colleagues have noticed this behavior (CDN sending
way more traffic than the customer's pipe can handle) from (I
believe) multiple CDNs. Not sure if it is intention on behalf of the
CDN or an error, but it has been on-going for several months if not
years.

It's not a healthy tcp flow if the number of packets associated with the
flow stays well in excess of the link capacity for a while... if you
have recourse to to l4 header flags you might find that it was an ack
flood or repeated retramission of the same PDUs. Either way someones
state machine has a bug.

joel