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Appendix C IP Addresses and Subnetting
ZyWALL 2WG User’s Guide
733
Figure 504
Subnetting Example: After Subnetting
In a 25-bit subnet the host ID has 7 bits, so each sub-network has a maximum of 2
7
– 2 or 126
possible hosts (a host ID of all zeroes is the subnet’s address itself, all ones is the subnet’s
broadcast address).
192.168.1.0 with mask 255.255.255.128 is subnet
A
itself, and 192.168.1.127 with mask
255.255.255.128 is its broadcast address. Therefore, the lowest IP address that can be assigned
to an actual host for subnet
A
is 192.168.1.1 and the highest is 192.168.1.126.
Similarly, the host ID range for subnet
B
is 192.168.1.129 to 192.168.1.254.
Example: Four Subnets
The previous example illustrated using a 25-bit subnet mask to divide a 24-bit address into two
subnets. Similarly, to divide a 24-bit address into four subnets, you need to “borrow” two host
ID bits to give four possible combinations (00, 01, 10 and 11). The subnet mask is 26 bits
(11111111.11111111.11111111.
11
000000) or 255.255.255.192.
Each subnet contains 6 host ID bits, giving 2
6
- 2 or 62 hosts for each subnet (a host ID of all
zeroes is the subnet itself, all ones is the subnet’s broadcast address).
Table 264
Subnet 1
IP/SUBNET MASK
NETWORK NUMBER
LAST OCTET BIT
VALUE
IP Address (Decimal)
192.168.1.
0
IP Address (Binary)
11000000.10101000.00000001.
00
000000
Subnet Mask (Binary)
11111111.11111111.11111111.
11
000000
Subnet Address:
192.168.1.0
Lowest Host ID: 192.168.1.1
Broadcast Address:
192.168.1.63
Highest Host ID: 192.168.1.62
Содержание ZYWALL 2 WG
Страница 1: ...www zyxel com ZyWALL 2WG Internet Security Appliance User s Guide Version 4 03 12 2007 Edition 1 ...
Страница 2: ......
Страница 8: ...Safety Warnings ZyWALL 2WG User s Guide 8 ...
Страница 42: ...List of Figures ZyWALL 2WG User s Guide 42 ...
Страница 50: ...List of Tables ZyWALL 2WG User s Guide 50 ...
Страница 52: ...52 ...
Страница 80: ...Chapter 2 Introducing the Web Configurator ZyWALL 2WG User s Guide 80 ...
Страница 100: ...Chapter 3 Wizard Setup ZyWALL 2WG User s Guide 100 ...
Страница 140: ...Chapter 4 Tutorial ZyWALL 2WG User s Guide 140 ...
Страница 145: ...145 PART II Network and Wireless LAN Screens 147 Bridge Screens 159 WAN Screens 165 DMZ Screens 201 Wireless LAN 211 ...
Страница 146: ...146 ...
Страница 158: ...Chapter 6 LAN Screens ZyWALL 2WG User s Guide 158 ...
Страница 171: ...Chapter 8 WAN Screens ZyWALL 2WG User s Guide 171 Figure 108 NETWORK WAN General ...
Страница 200: ...Chapter 8 WAN Screens ZyWALL 2WG User s Guide 200 ...
Страница 238: ...238 ...
Страница 258: ...Chapter 11 Firewall ZyWALL 2WG User s Guide 258 Figure 159 SECURITY FIREWALL Rule Summary Edit ...
Страница 270: ...Chapter 11 Firewall ZyWALL 2WG User s Guide 270 Figure 170 My Service Firewall Rule Example Rule Summary Completed ...
Страница 300: ...Chapter 13 Content Filtering Reports ZyWALL 2WG User s Guide 300 ...
Страница 313: ...Chapter 14 IPSec VPN ZyWALL 2WG User s Guide 313 Figure 199 SECURITY VPN VPN Rules IKE Edit Gateway Policy ...
Страница 322: ...Chapter 14 IPSec VPN ZyWALL 2WG User s Guide 322 Figure 202 SECURITY VPN VPN Rules IKE Edit Network Policy ...
Страница 348: ...Chapter 14 IPSec VPN ZyWALL 2WG User s Guide 348 ...
Страница 360: ...Chapter 15 Certificates ZyWALL 2WG User s Guide 360 Figure 229 SECURITY CERTIFICATES My Certificates Create Basic ...
Страница 378: ...Chapter 15 Certificates ZyWALL 2WG User s Guide 378 ...
Страница 380: ...Chapter 16 Authentication Server ZyWALL 2WG User s Guide 380 Figure 239 SECURITY AUTH SERVER Local User Database ...
Страница 384: ...384 ...
Страница 426: ...Chapter 20 Bandwidth Management ZyWALL 2WG User s Guide 426 ...
Страница 479: ...479 PART V Logs and Maintenance Logs Screens 481 Maintenance 511 ...
Страница 480: ...480 ...
Страница 485: ...Chapter 26 Logs Screens ZyWALL 2WG User s Guide 485 Figure 304 LOGS Log Settings ...
Страница 510: ...Chapter 26 Logs Screens ZyWALL 2WG User s Guide 510 ...
Страница 530: ...530 ...
Страница 558: ...Chapter 30 WAN and Dial Backup Setup ZyWALL 2WG User s Guide 558 ...
Страница 564: ...Chapter 31 LAN Setup ZyWALL 2WG User s Guide 564 ...
Страница 570: ...Chapter 32 Internet Access ZyWALL 2WG User s Guide 570 ...
Страница 574: ...Chapter 33 DMZ Setup ZyWALL 2WG User s Guide 574 ...
Страница 578: ...Chapter 34 Route Setup ZyWALL 2WG User s Guide 578 ...
Страница 582: ...Chapter 35 Wireless Setup ZyWALL 2WG User s Guide 582 ...
Страница 594: ...Chapter 37 IP Static Route Setup ZyWALL 2WG User s Guide 594 ...
Страница 614: ...Chapter 38 Network Address Translation NAT ZyWALL 2WG User s Guide 614 ...
Страница 632: ...Chapter 40 Filter Configuration ZyWALL 2WG User s Guide 632 ...
Страница 668: ...Chapter 44 System Maintenance Menus 8 to 10 ZyWALL 2WG User s Guide 668 ...
Страница 672: ...Chapter 45 Remote Management ZyWALL 2WG User s Guide 672 ...
Страница 680: ...Chapter 46 IP Policy Routing ZyWALL 2WG User s Guide 680 ...
Страница 685: ...685 PART VII Troubleshooting and Specifications Troubleshooting 687 Product Specifications 693 ...
Страница 686: ...686 ...
Страница 692: ...Chapter 48 Troubleshooting ZyWALL 2WG User s Guide 692 ...
Страница 702: ...Chapter 49 Product Specifications ZyWALL 2WG User s Guide 702 ...
Страница 704: ...704 ...
Страница 712: ...Appendix A Pop up Windows JavaScripts and Java Permissions ZyWALL 2WG User s Guide 712 ...
Страница 740: ...Appendix D Common Services ZyWALL 2WG User s Guide 740 ...
Страница 768: ...Appendix G Legal Information ZyWALL 2WG User s Guide 768 ...
Страница 774: ...Appendix H Customer Support ZyWALL 2WG User s Guide 774 ...