IPSEC Overhead

[lovefunlove]

Hello Guys ,

Can you please let me know what is the theoritical bandwidth over head when we use IPsec encryption in respect with simple GRE Tunnel .

Waiting for your expert comments.

Regards,

Max

[turnbull]

Hi Max,

GRE is 24 bytes

IPSEC is not so cut and dried.

"IPSec can make fragmentation problems worse, because it lengthens each IP packet by one, or possibly two, IP headers. These added headers vary in length by choice of IPSec protocols (and whether IntraPort's "NAT transparency" is also in use), but empirically they do not exceed 80 bytes per packet"

http://cisco.com/en/US/products/hw/routers/ps4081/products_tech_note09186a0080094268.shtml

http://cisco.com/en/US/tech/tk827/tk369/technologies_tech_note09186a0080093f1f.shtml

http://cisco.com/en/US/products/sw/iosswrel/ps1839/products_feature_guide09186a0080087ae1.html

Cheers,

Paul.