Figure 28 Sample Control Tunnel Environment - Nortel Contivity 1100 Configuration Manual

Chapter 7 Configuring control tunnels 139

Figure 28 Sample control tunnel environment

Branch office control tunnels allow anyone on the configured network to
communicate with the Nortel VPN Router being managed. This allows a Nortel
VPN Router to communicate with various systems within a company's network
operations center or corporate headquarters (the Cleveland private network).
A user control tunnel allows a Nortel VPN Client to communicate with a Nortel
VPN Router that is being managed. This allows network management personnel
from anywhere in the world access to the management tasks.
If you work at a NOC in Cleveland and you manage a customer's Nortel VPN
Router that is located in Boston, you would want to use control tunnels. On one
end of the control tunnel (the Nortel VPN Router under management), access is
always restricted to the management address only. Access to the Boston Nortel
VPN Router is limited. The Cleveland end of the tunnel could allow access to its
entire private network. This allows multiple systems in your Cleveland NOC to
communicate with the management address only of the Boston Nortel VPN
Router; or for the Boston Nortel VPN Router to use remote servers (FTP, DHCP,
RADIUS, and DNS servers) on the Cleveland private network.
Nortel VPN Router Configuration — Basic Features