ZyXEL Communications 128MH - Manual (Page 55)

Prestige 128MH PSTN Router/Hub
3-3 Chapter 3 Internet Access Application
Table 3-1. Subnet Mask Notation (continued)
Number of Bits Dot Decimal Value
3 224
4 240
5 248
6 252
7 254
8 255
Table 3-2 lists some examples of IP subnet masks and the number of hosts that are allowed.
Consult your network administrator or MIS specialist if you are unsure of this value.
Table 3-2. Examples of IP Subnet Masks
IP Subnet Mask Number of Host IDs Number of Bits
255.255.255.0 254 24
255.255.255.128 126 25
255.255.255.192 62 26
255.255.255.224 30 27
255.255.255.255 1 32
An IP address consists of two parts, the network ID and the host ID. The IP Subnet Mask is used
to specify the network ID portion of the address, expressed in dotted decimal notation.The
Prestige will automatically calculate this mask based on the IP address that you assign. Unless
you have special need for subnetting, use the default mask as calculated by the Prestige.