2-4
Vanguard Routing Model
WAN Adapter
WAN Adapter
Introduction
The WAN Adapter is the logical function that connects the IP Forwarder to the WAN
ports. Specifically, the WAN Adaptor:
• Implements the LAN connection (LCON)
• Performs the WAN encapsulation
• Establishes the remote connections using SVCs or PVCs
• Collects and maintains statistics on each remote LAN connection
• Controls data flow
What is an LAN
Connection -
LCON?
The WAN Adaptor connects the IP Forwarder to the WAN ports via a virtual circuit
called the LAN Connection, LCON. LCONs uses X.25 based addressing to establish
virtual circuits.
LAN Protocols
LAN protocols serve two purposes:
• Access termination such as traditional serial protocols
• Routing LAN data along proper WAN paths
The Vanguard WAN Adapter allows Vanguard LAN software to implement a more
efficient layer of routing.
An overlay network that the LAN routing functions see is superimposed on top of
the actual virtual circuit network and physical network implemented by the Motorola
access devices.
WAN Adaptor
Interconnections
Figure 2-2 shows how the WAN Adapter is used to provide a LAN overlay network.
Figure 2-2. WAN Adapter Interconnections
X.25
Stack
Up To 2000
Connections
Up To 250
Bridge
Links
Up To 254
Router
Interfaces
PVC
SVC
SVC
FR-DCE Port
X.25 Port
FR-DTE Port
Bridge
Router
Handler
LAN Port
WAN Adapter
X.25
Stack
