Subject: VPN Questions

From: "Ashish Chaurasia" <[email-masked]>
Date: Thu, 13 Sep 2001 17:24:41 -0700

I m working on VPN using IPSec protocol. But I have some   doubts in my mind. 
 
1.  What is the advantage of implementing VPN using IPSec protocol that works at Network layer, even though the implementations of VPN at Data Link layer are available such as L2TP,L2F, PPTP etc ?

2. What extra does VPN support in comparision to the combination of Firewall and PKI ?

3. What are the advantages of having security at Network Layer than having security at other layers of TCP/IP stack.

regards
Ashish