HP 200 Series Services And Applications page 120

Internet Protocol Routing Service
The IP Network Interface Definition
The IP Network Interface Definition
The HP router must have an IP interface defined for each attached network
using IP routing. On the HP routers, "circuit groups" connect the router to its
networks. On the other end of each circuit group on this router is, in the
case of a WAN link, another router or gateway or host, or in the case of a
LAN link, a network or subnetwork.
If one link has more than one network or subnetwork attached, then each
subnetwork must have its own network interface definition with its own
unique IP address. Note that the nodes on the two subnetworks will always
communicate with each other through the router even if they are on the
same cable. For more than one subnetwork on a port, configure that circuit
group in more than one network interface definition, each with a different IP
address. Suppose, for example, that LAN interface B, shown in figure 3,
accesses networks N and N . In this case, you need two IP addresses. This
x y
is because one address for interface B is needed to access LAN x, and
another address for interface B is needed to access LAN y.
Figure 3. Sample Topology for Multiple Network Interface Definitions
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