Appendix C IP Addresses and Subnetting
P-660RU-T v2 User’s Guide
144
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 88
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 40
Alternative Subnet Mask Notation (continued)
SUBNET MASK
ALTERNATIVE
NOTATION
LAST OCTET
(BINARY)
LAST OCTET
(DECIMAL)
Summary of Contents for P-660RU-T3 V2
Page 2: ......
Page 7: ...Safety Warnings P 660RU T v2 User s Guide 7...
Page 8: ...Safety Warnings P 660RU T v2 User s Guide 8...
Page 10: ...Contents Overview P 660RU T v2 User s Guide 10...
Page 16: ...Table of Contents P 660RU T v2 User s Guide 16...
Page 20: ...List of Figures P 660RU T v2 User s Guide 20...
Page 23: ...23 PART I Introduction Introducing the ZyXEL Device 25 Introducing the Web Configurator 29...
Page 24: ...24...
Page 34: ...Chapter 2 Introducing the Web Configurator P 660RU T v2 User s Guide 34...
Page 35: ...35 PART II Wizard Wizard Setup 37...
Page 36: ...36...
Page 48: ...Chapter 3 Wizard Setup P 660RU T v2 User s Guide 48...
Page 50: ...50...
Page 52: ...Chapter 4 Password Setup P 660RU T v2 User s Guide 52...
Page 68: ...Chapter 6 WAN Setup P 660RU T v2 User s Guide 68...
Page 78: ...Chapter 10 Remote Management Configuration P 660RU T v2 User s Guide 78...
Page 90: ...Chapter 11 Universal Plug and Play UPnP P 660RU T v2 User s Guide 90...
Page 101: ...101 PART IV Maintenance and Troubleshooting Maintenance 103 Troubleshooting 115...
Page 102: ...102...
Page 120: ...120...
Page 124: ...Appendix A Product Specifications P 660RU T v2 User s Guide 124...
Page 156: ...Appendix E Virtual Circuit Topology P 660RU T v2 User s Guide 156...
Page 160: ...Appendix F Legal Information P 660RU T v2 User s Guide 160...