The structure of the IP header may be a 5 words of 32 bits including the following fields:
- Version (4bits) , IHL (4bits) , TOS (8 bits), Total length(16 bits)
- Identification (16 fields), flags(3 bits) , fragment offset ( 13 bits)
- TTL (8 bits ) , Protocol (8 bits) , Header checksum (16 bits)
- Source Address (32 bits)
- Destination Address ( 32 bits)
- Options + Padding (32 bits)
When IP Security is applied in the tunnel mode, the network packet (including the original IP header) is encapsulated by ESP or AH headers and a new IP header is inserted as an outer header ; So:
Q1: The inner IP address of the inner (original) IP header becomes unknown.. By which sense that it becomes unknown?
Is it encrypted or became hidden (by the meaning that if the traffic is captured ; it wouldn't appear)?
Q2: What are the effects of encapsulating the inner (original) IP header with ESP or AH headers on each field of its structure in the way of encryption or being hidden?
I'm waiting for answers