VTI vs GRE

cedar_lee · ‎11-13-2008

Which one would you prefer, VTI or GRE?

As far as I know, VTI has less overhead, less configuration CLI while it does not provide keep alive.

Joseph W. Doherty · ‎11-13-2008

If the VTI (virtual tunnel interface) you're thinking of is the one used by IPSec, it would seem to have more overhead and more configuation than just GRE. Or where you thinking VTI vs. IPSec/GRE tunnel?

cedar_lee · ‎11-13-2008

Yes, you are right. GRE over IPsec. Thanks for correcting me.

Michal Gurbski · ‎05-08-2010

Hi,

GRE headers adds extra 4 bytes, thus reducing the bandwidth for sending encrypted data.

See attachment.

And info from http://www.nil.com/ipcorner/IPsecVPN3/

"The main difference is that VTIs only support IP (unicast and multicast), while GRE also supports other protocols. VTIs also were not available on all platforms when they were first introduced."

Kind regards,

Michal