User's Manual

EnRoute500 User’s Guide
TR0149 Rev. C5
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11 Connecting an EnRoute500 Gateway to a WAN
The options for connecting an EnRoute500 gateway to a WAN are described below.
11.1 Manual Configuration
An EnRoute500 gateway can be directly connected to a WAN without using Network Address
Translation. With this gateway configuration, the router on the network that the gateway is
attached to must be configured to forward the mesh subnet and the LAN subnets to the
gateway’s Ethernet IP address. The subnets that need to be forwarded are:
Class B subnet: <sys.id.lanprefix>.<sys.id.mesh>.0.0
Class C subnet: <sys.id.meshprefix>.<sys.id.mesh>.0
The subnet information can be retrieved from the ‘sys’ interface as shown below.
> use sys
sys> get id.*
sys.id.lanprefix = 10
sys.id.mesh = 2
sys.id.meshprefix = 172.29
sys.id.node = 4
With this configuration, the subnets the router would need to forward to the gateway are
10.2.0.0/255.255.0.0 and 172.29.2.0/255.255.255.0.
11.2 Network Address Translation (NAT)
Network Address Translation (NAT) isolates a mesh cluster from the WAN network that its
gateway is connected to. The mesh nodes and their client devices are able to communicate
with devices connected to the external network that the mesh gateway is connected to.
However, devices on the external network cannot initiate communication with any nodes in the
mesh cluster, or their clients, other than the mesh cluster gateway.
The advantages of using NAT are:
• You can easily attach a mesh cluster to an existing network. You do not need to modify any
settings on the router on your existing network to forward packets to the addresses used in
your mesh cluster.
• The nodes in the mesh cluster are shielded from the network that the gateway is attached
to.