IP Routing
6-2
8000-A2-GB21-20
November 1997
With destination-based routing, the destination address of the packet being sent
is compared to the destination address entries in the routing table. The
destination address could possibly match one or more of three types of
addresses in the routing table. It could match a:
Host route address (that is, a specific destination IP address) e.g., 135.1.3.5,
or
Subnet route, e.g., 135.1.3.0, or
Network route, e.g., 135.1.0.0
If a match is found for more than one destination address, the order of
precedence is:
1. Host route
2. Subnet route
3. Network route
4. Default route
Therefore, the packet is sent to the next-hop address specified for that
destination which matches and has the highest precedence.
A packet routed through the HotWire DSLAM that has a destination address not
matching any entry in the routing table is dropped unless a default route is
specified. If a default route is specified using the conventional address 0.0.0.0 as
the destination IP address, the packet is sent to the associated next-hop address.
Static Routes for Static IP Addressing
If you plan to use static addressing, then you will need to create static routes to
route to the end-user systems. Use the following routing table form:
Host/Net, Subnet Mask, Next Hop, Pref, S/D, PA
Where:
The
Host/Net is one of the following:
— A host address (for example, the specific IP address of an RTU or
end-user system), or
— A subnet or network portion of a destination or source IP address, or
— The default route, which is defined to be 0.0.0.0.
The
Subnet Mask for host, subnet, or network. This is not applicable to
default routes.
The
Next Hop is the IP address to which the given datagram should be
forwarded. For example, the IP address of the router connected to the LAN or
the HotWire RTU.
