User`s guide

Configuring IP Routing
Introduction to IP routing on the Pipeline
2-6 Preliminary January 30, 1998 Pipeline User’s Guide
Note:
A host route is a special case IP address with a subnet mask of /32; for
example, 198.5.248.40/32. Host routes are required for a dial-in host.
The broadcast address of any subnet is always all ones. The network base address
represents the network cable itself, which is always address 0. For example, if the
Pipeline configuration assigns the following address to a remote Pipeline router:
198.5.248.120/29
the Ethernet attached to that router has the following address range:
198.5.248.120 — 198.5.248.127
The “0” address (198.5.248.120) is reserved for the cable itself. The broadcast
address is 198.5.248.127, and the router itself uses one of the host addresses.
That leaves five remaining host addresses on that remote subnet, which can be
assigned in any order to five hosts on that subnet.
As another example, if the Pipeline configuration assigns the following address
to a remote router:
192.168.8.64/26
the Ethernet attached to that router has the following address range:
192.168.8.64 – 192.168.8.127
255.255.255.224 /27 30 hosts + 1 broadcast, 1 network base
255.255.255.240 /28 14 hosts + 1 broadcast, 1 network base
255.255.255.248 /29 6 hosts + 1 broadcast, 1 network base
255.255.255.252 /30 2 hosts + 1 broadcast, 1 network base
255.255.255.254 /31 invalid netmask (no hosts)
255.255.255.255 /32 1 host — a host route
Table 2-2. Standard netmasks and Ascend netmask notation (continued)
Netmask Ascend notation Number of host addresses