User`s guide

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If a static route is “pointing” at an Ethernet interface then optionally a gateway IP address
can be added. If a gateway IP address is not added then the gateway IP address configured
for the Ethernet interface itself will be used automatically.
Default Routes
Default routes can be added by configuring a route in Configuration - Network > IP
Routing/Forwarding > Static Routes > Default Route n (where n is an instance
number).
Default routes will match packets with any destination IP address (when in service).
If a default route is configured, packets with destination IP addresses that do not match any
of the dynamic or static routes will be sent out the interface specified in the first “in service”
default route.
Routing modes
The TransPort has 2 routing modes available, these are:
TransPort routing mode
This is the original routing method and may be seen on existing installations.
CIDR routing mode
Now enabled by default on new TransPort routers.
The CLI command to switch between the 2 modes is:
ip 0 cidr [off|on]
TransPort routing mode
CIDR routing is disabled
When the TransPort receives an IP packet to route, the routing table is used to decide
through which interface to send the packet.
Usually the destination IP address of the IP packet is compared with the IP Address and
Mask of each entry in the routing table in index order regardless of the order in the routing
table or length of mask.
There may be more than one match and in this case the index number of the route is taken
into account. The index number is simply the route number in the config, Static Route 0 or
1 is index 0 or 1
Static routes are checked first, then dynamic routes, then default routes.
CLI command:
ip 0 cidr off
CIDR routing mode
CIDR routing is enabled
When the TransPort receives an IP packet to route, the routing table is used to decide
through which interface to send the packet.
Usually the destination IP address of the IP packet is compared with the IP Address and
Mask of each entry in the routing table.
There may be more than one match and in this case the most specific route is used to route
the packet. Ie, a matching /24 route is used before a matching /16 route.