Calculating Traffic overhead

[mnlatif]

Hi,

I am trying to calculate the protocol overhead for IPSec and MPLS Traffic. Below is what i have come up so far, please correct for any mistakes

1. Ethernet Overhead = 26 bytes (w/o VLAN tagging)

18 (header + Trailer) + 6 (LLC + SNAP)

2. IP Overhead = 20 bytes

3. TCP Overhead = 20 bytes

Can anyone guide me for

4. IPSec overhead ? (Using esp-md5-hmac for AH and esp-des for ESP)

5. MPLS packet overhead ? (Using MPLS\BGP VPNs)

Thanks \\ Naman

[ebreniz]

You can have a look at this document for more details of IPSEC headers

ftp://ftp.isi.edu/in-notes/rfc2402.txt