IPSec VPN throughput

L3 Networker

IPSec VPN throughput

Hi all,

I have a IPSec VPN between a PA200 and a PA220.

Now i'm transporting a file from the pa200 network via ftp through the side-to-side tunnel to the pa220 network. The connection between the PAs is a 300mbits synchronous connection.


The dataplane cpu goes up to over 90% with PA200 and the bandwidth reaches only low 10mbyte/s. The interesting thing is, if I transfer 10 files at the same time, the speed goes up to about 20-25mbyte. Dataplane CPU is around 90-95% again.


What could be the reason for this? How do I get more speed?

Tags (3)
L3 Networker

Re: IPSec VPN throughput

That was a stupid question. The solution can be found in the technical data sheet. the PA200 can only 50mbits as ipsec tunnel. That explains my problem.

Community Team Member

Re: IPSec VPN throughput

Hi @clonesheep ,


It wasn't stupid ... real users don't read manuals ! XD





Cheers !


L2 Linker

Re: IPSec VPN throughput

10Mbit/s is a far cry from 50. What's more likely to be your problem is that performance is getting degraded due to fragmentation. Try dropping the MTU on your tunnel interfaces to about 1400 and make sure MSS is getting clamped. Also check your algorithms. You should be using AES instead of 3DES, try GCM instead of CBC, etc.

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