User Manual

NovaRoam EH900 User Manual
V. 1.1
Page 65
gateway. It is also necessary to add static routes within each NovaRoam. The
NovaRoam from Subnet 1 must have a static route to Subnet 2, using the
wireless interface of the NovaRoam from Subnet 2 as the gateway. The route
should be set up like this:
192.168.2.0 255.255.255.0 192.168.3.2 1
Network Netmask Gateway Metric
It is recommended that all hosts from Subnet 2 use 192.168.2.1 as their default
gateway. As an alternative, manual routes can be entered within each host’s
routing table. The NovaRoam from Subnet 2 must have a static route to Subnet
1, using the wireless interface of the NovaRoam from Subnet 1 as the gateway.
This route should be set up like this:
192.168.1.0 255.255.255.0 192.168.3.1 1
Network Netmask Gateway Metric
Note: It is important to understand that there are actually three subnets in this
example: Subnet 1, Subnet 2, and the wireless network.
AODV
The NovaRoam uses a routing algorithm called AODV (Ad hoc On-demand
Distance Vector) that works dynamically to establish and maintain routes. AODV
is an “on demand” routing algorithm, meaning that it builds routes between nodes
only as requested by source nodes. These routes are maintained only as long as
required by the source nodes.
AODV creates routes using a route request / route reply query cycle. When a
source node requires a route to a destination for which it does not already have a
route, it broadcasts a route request (RREQ) packet across the wireless network.
Nodes receiving this packet update their information for the source node and
create reverse pointers to the source node in their route tables. A node that
receives the RREQ will send a route reply (RREP) if it is either the destination or
if it has a route to the destination with a corresponding sequence number greater
than or equal to that contained in the RREQ. If this is the case, the node sends a