I'm trying to draw the packets in a network that uses an IPSec tunnel for security. More specifically: a laptop user using a public access point wants to query Google through an IPSec tunnel to a home PC. I'm trying to draw the packet between the laptop and the public access point.
If I understand it correctly the packets will have the following layout:
MacTo - MacFrom - IPSource - IPDestination - SourcePort - DestinationPort - [Encrypted source IP - Encrypted destination IP - Encrypted source port - Encrypted destination port - data]
in which the encrypted packet is placed between the brackets.
I'm wondering how to fill in the ports in this setting.
- SourcePort: I assume just a random port of the laptop.
- DestinationPort: I assume this is the port of the IPSec gateway service.
- Encrypted source port: Is this the same as SourcePort? Is this port modified by the IPSec gateway before the packet is forwarded to Google?
- Encrypted destination port: 80 (http for the Google request)
Can anyone confirm if my assumptions are correct or indicate how I should fill in "Encrypted source port"?
Thanks in advance