Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

IPSec Packet Size Calculator - SHA256 digest?

Hi,

I recently discovered the IPSec Packet Size Calculator in this forum (see attachment).

It is very helpful to calculate the overhead when using IPSec, esp. DMVPN.

Unforunately it doesn't contain options for the following hashes:

  esp-sha256-hmac  ESP transform using HMAC-SHA256 auth

  esp-sha384-hmac  ESP transform using HMAC-SHA384 auth

  esp-sha512-hmac  ESP transform using HMAC-SHA512 auth

Where can I find information about how big the digest will be when using "esp-sha256-hmac" in my transform set?

Is somebody able and willing to implement these new options in the calculator?

Thanks

Everyone's tags (5)
1 ACCEPTED SOLUTION

Accepted Solutions
Cisco Employee

This was just published about

This was just published about a week ago:

https://cway.cisco.com/tools/ipsec-overhead-calc/ipsec-overhead-calc.html

Thanks,

Wen

6 REPLIES
New Member

IPSec Packet Size Calculator - SHA256 digest?

Hi,

can nobody give me a hint?

:-)

New Member

We are looking for similar

We are looking for similar information while troubleshooting what looks to be a fragmentation issue with our dmvpn ipsec solution. We have implemented AES128 and SHA256. I found the following for the lower hash/hmacs, but it stops with SHA-1. http://www.cisco.com/c/en/us/td/docs/interfaces_modules/services_modules/vspa/configuration/guide/ivmsw_book/ivmvpnb.html#wp2055737. Did you find any information? Anyone else?
New Member

up until now I didn't find

up until now I didn't find any reliable information either.

I contacted the authour of the above html file, but there is no new version...

Would also greatly appreciate an update :-)

Cisco Employee

This was just published about

This was just published about a week ago:

https://cway.cisco.com/tools/ipsec-overhead-calc/ipsec-overhead-calc.html

Thanks,

Wen

New Member

Thanks Wen!!Thats exactly

Thanks Wen!!

Thats exactly what I was looking for!

Cisco Employee

Sebastian: Good to know the

Sebastian:

 

Good to know the tool is useful to you. If you have any ideas on how it can be enhanced, provide your feedback using the feedback link, and we'll do what we can.

 

Thanks,

Wen

2376
Views
0
Helpful
6
Replies