
1-2
N e t P a t h 2 0 0 0
Figure 1.1
Typical Customer Network Configuration.
The simplest fail-over configuration uses a static secondary default or subnet
route in the branch office router via the NetPath 2000’s interface. When the
branch office router detects a failure of the primary default or headquarters
route over the T1 frame relay network, it switches its routing to the backup
Ethernet port and the NetPath 2000. The NetPath 2000 automatically connects
to the Cingular wireless network and routes traffic to the corporate
headquarters using the alternative wireless network.
When the main network connection is restored, the branch office router falls
back to using only this Frame Relay Network and ceases sending traffic via
the NetPath 2000. The NetPath 2000 continuously monitors and maintains its
wireless connection via periodic keep-alive packets in the event it is required
to provide network connectivity. While the main network connection is
providing connectivity, the branch office router should not send any idle or
keep-alive WAN traffic to the NetPath 2000 to avoid creating unnecessary
wireless traffic, but it may ping the NetPath 2000 local interface.
NetPath 2000 Secure Primary WAN Operation
The NetPath 2000 offers a method for secure network connectivity (see Figure
1.2). It uses Cingular’s 3G wireless data network as the primary means to
route mission-critical information employing internal Virtual Private Network
(VPN) functionality to maintain end-to-end security.
In a typical customer network, the branch offices are connected to their
headquarters through the NetPath 2000 and the Cingular wireless network.
The Cingular wireless network assigns the NetPath 2000 a network IP address
via a Point-to-Point Protocol (PPP) connection. The NetPath 2000, using
Network Address Translation (NAT) and DHCP, provides private address
Branch Offices
Branch Offices
Servers
Corporate Headquarters
Corporate Headquarters
Branch Offices
Branch Offices
Back-end
Frame Relay
or
VPN connection
Frame Relay T1
Branch Office
Router
Carrier Frame
Relay Service
Wireless
Carrier
Network
Branch Office
Router
Frame Relay T1
Frame Relay T1s
Branch Offices
Branch Offices
Servers
Corporate Headquarters
Corporate Headquarters
Branch Offices
Branch Offices
Back-end
Frame Relay
or
VPN connection
Frame Relay T1
Branch Office
Router
Carrier Frame
Relay Service
Wireless
Carrier
Network
Branch Office
Router
Frame Relay T1
Frame Relay T1s