How to calculate encryption on bandwidth

[UCrypto]

I would like to know how to calculate the bandwidth for aes-256 encryption.

it is only increase cpu usage when encapsulation process ? 

[UCrypto]

Help me Please

[Joseph W. Doherty]

"it is only increase cpu usage when encapsulation process ? "

No, it also increase bandwidth consumption.

"I would like to know how to calculate the bandwidth for aes-256 encryption."

If varies, per how exactly you've configured it. But typically it adds 80 to 100 bytes per packet, and it may cause packet fragmentation which then adds the bandwidth overhead of L2 and IP per fragment packet (about 50 bytes).

[UCrypto]

If i confiugre TCP MSS is 1350 ,how much bandwidth ?

will it take more delay time only ?

or do we need to calculate more bandwidth for them ,eg 20 % 10 % more than normal traffic ?

[balaji.bandi · Accepted solution]

There is good reading :

https://packetpushers.net/tcp-over-ip-bandwidth-overhead/

There is good tool for your to calculated based on your requirement.

https://wand.net.nz/~perry/max_download.php?bits_per_second=10000000000&ack_size=40&no_delayed_acks=2&mss=1460&rtt=1&wsize=65536&ploss=0.0

http://www.t1shopper.com/tools/calculate/downloadcalculator.php

Hope this will help you. ?

[Joseph W. Doherty]

"If i confiugre TCP MSS is 1350 ,how much bandwidth ?"

That's still a "it depends" answer. Balaji's post provides links that show the range of overhead vary (about) 9% to 12,000% (and that's without getting into fragmentation).

"will it take more delay time only ?"

More time (to transmit) - yes.

"or do we need to calculate more bandwidth for them ,eg 20 % 10 % more than normal traffic ?"

You can calculate the overhead if you know all the variables of your traffic and IPSec configuration settings.