Barracuda Networks NG Network Access Client SP4 Administrator's Manual page 173

The following steps are carried out when a connection is to be established:
1.) Client opens a socket on the server, starts authentication and requests configuration
2.) Client receives configuration (IP, subnet mask, WINS, DNS, ...)
3.) Client sends received information to the SPAC
4.) Client triggers ipconfig/renew for the Barracuda NG VPN Virtual Adapter
5.) SPAC answers DHCP requests for the Adapter with the configuration data
6.) Operating system reconfigures the Virtual Adapter
7.) VPN Service introduces additional routes
8.) The corresponding rule set for the Barracuda NG Personal Firewall is implemented.
Fig. 12–2 Connection procedure
User space
NG VPN
component
2 1
Kernel
Device
Hardware
171 Barracuda NG Network Access Client - Administrator's Guide
3
4
5
SPAC DHCP
Barracuda Networks VPN
NG VPN
Virtual Adapter
Ethernet
1
2
Step 1
Step 2
Step 3
Step 4
Step 5
server
Port 691 or
443 via Proxy