ZyXEL Communications NWD-210N - FOR MAC V1.00 Guía de usuario descargar pdf (Pagina 198)

Appendix C IP Addresses and Subnetting

NBG5715 User’s Guide

198

Subnetting

You can use subnetting to divide one network into multiple sub-networks. In the following example

a network administrator creates two sub-networks to isolate a group of servers from the rest of the

company network for security reasons.

In this example, the company network address is 192.168.1.0. The first three octets of the address

(192.168.1) are the network number, and the remaining octet is the host ID, allowing a maximum

of 2

– 2 or 254 possible hosts.

The following figure shows the company network before subnetting.

Figure 125 Subnetting Example: Before Subnetting

You can “borrow” one of the host ID bits to divide the network 192.168.1.0 into two separate sub-

networks. The subnet mask is now 25 bits (255.255.255.128 or /25).

The “borrowed” host ID bit can have a value of either 0 or 1, allowing two subnets; 192.168.1.0 /25

and 192.168.1.128 /25.

255.255.255.224 /27 1110 0000 224

255.255.255.240 /28 1111 0000 240

255.255.255.248 /29 1111 1000 248

255.255.255.252 /30 1111 1100 252

Table 78 Alternative Subnet Mask Notation (continued)

SUBNET MASK

ALTERNATIVE

NOTATION

LAST OCTET

(BINARY)

LAST OCTET

(DECIMAL)

1 2 ... 193 194 195 196 197 198 199 200 201 202 203 ... 291 292

Sin comentarios

ZyXEL Communications NWD-210N - FOR MAC V1.00 Guía de usuario Pagina 198