![background image](http://html.mh-extra.com/html/zyxel-communications/xgs-4728f/xgs-4728f_user-manual_945804412.webp)
Appendix B IP Addresses and Subnetting
XGS-4728F User’s Guide
412
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
8
– 2 or 254 possible hosts.
The following figure shows the company network before subnetting.
Figure 239
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.
The following figure shows the company network after subnetting. There are now two sub-
networks,
A
and
B
.
255.255.255.192
/26
1100 0000
192
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 158
Alternative Subnet Mask Notation (continued)
SUBNET MASK
ALTERNATIVE
NOTATION
LAST OCTET
(BINARY)
LAST OCTET
(DECIMAL)
Summary of Contents for XGS-4728F
Page 2: ......
Page 8: ...Safety Warnings XGS 4728F User s Guide 8 ...
Page 24: ...24 ...
Page 30: ...Chapter 1 Getting to Know Your Switch XGS 4728F User s Guide 30 ...
Page 34: ...Chapter 2 Hardware Installation and Connection XGS 4728F User s Guide 34 ...
Page 42: ...Chapter 3 Hardware Overview XGS 4728F User s Guide 42 ...
Page 44: ...44 ...
Page 78: ...Chapter 7 System Status and Port Statistics XGS 4728F User s Guide 78 ...
Page 92: ...Chapter 8 Basic Setting XGS 4728F User s Guide 92 ...
Page 94: ...94 ...
Page 114: ...Chapter 9 VLAN XGS 4728F User s Guide 114 ...
Page 118: ...Chapter 10 Static MAC Forward Setup XGS 4728F User s Guide 118 ...
Page 148: ...Chapter 14 Bandwidth Control XGS 4728F User s Guide 148 ...
Page 162: ...Chapter 17 Link Aggregation XGS 4728F User s Guide 162 ...
Page 186: ...Chapter 21 Policy Rule XGS 4728F User s Guide 186 ...
Page 230: ...Chapter 25 AAA XGS 4728F User s Guide 230 ...
Page 268: ...268 ...
Page 324: ...324 ...
Page 332: ...Chapter 38 Maintenance XGS 4728F User s Guide 332 ...
Page 358: ...Chapter 41 Syslog XGS 4728F User s Guide 358 ...
Page 366: ...Chapter 42 Cluster Management XGS 4728F User s Guide 366 ...
Page 370: ...Chapter 43 MAC Table XGS 4728F User s Guide 370 ...
Page 374: ...Chapter 44 IP Table XGS 4728F User s Guide 374 ...
Page 378: ...Chapter 46 Routing Table XGS 4728F User s Guide 378 ...
Page 382: ...382 ...
Page 392: ...Chapter 48 Troubleshooting XGS 4728F User s Guide 392 ...
Page 402: ...Chapter 49 Product Specifications XGS 4728F User s Guide 402 ...
Page 404: ...404 ...
Page 408: ...Appendix A Legal Information XGS 4728F User s Guide 408 ...