Appendix F IP subnetting
261
Nortel Business Secure Router 252 Configuration — Advanced
Divide the network 192.168.1.0 into two separate subnets by converting one of
the host ID bits of the IP address to a network number bit. The borrowed host ID
bit can be either 0 or 1, thus giving two subnets; 192.168.1.0 with mask
255.255.255.128 and 192.168.1.128 with mask 255.255.255.128.
The remaining 7 bits determine the number of hosts each subnet can have. Host
IDs of all zeros represent the subnet itself and host IDs of all ones are the
broadcast address for that subnet, so the actual number of hosts available on each
subnet in the example above is 2
7
– 2 or 126 hosts for each subnet.
Note:
In the following charts, shaded or bolded last-octet bit values
indicate host ID bits borrowed to form network ID bits. The number of
borrowed host ID bits determines the number of subnets you can have.
The remaining number of host ID bits (after borrowing) determines the
number of hosts you can have on each subnet.
Table 55
Subnet 1
Network number
Last Octet bit value
IP Address
192.168.1.
0
IP Address (Binary)
11000000.10101000.00000001.
0
0000000
Subnet Mask
255.255.255.
128
Subnet Mask (Binary)
11111111.11111111.11111111.
1
0000000
Subnet Address: 192.168.1.0
Lowest Host ID: 192.168.1.1
Broadcast Address:
192.168.1.127
Highest Host ID: 192.168.1.126
Table 56
Subnet 2
Network number
Last octet bit value
IP Address
192.168.1.
128
IP Address (Binary)
11000000.10101000.00000001.
1
0000000
Subnet Mask
255.255.255.
128
Subnet Mask (Binary)
11111111.11111111.11111111.
1
0000000
Subnet Address: 192.168.1.128
Lowest Host ID: 192.168.1.129
Broadcast Address:
192.168.1.255
Highest Host ID: 192.168.1.254
Содержание 252
Страница 13: ...Contents 13 Nortel Business Secure Router 252 Configuration Advanced SIP Register Server 337 RTP 337 Index 341 ...
Страница 14: ...14 Contents NN47923 501 ...
Страница 20: ...20 Figures NN47923 501 ...
Страница 24: ...24 Tables NN47923 501 ...
Страница 30: ...30 Preface NN47923 501 ...
Страница 42: ...42 Chapter 1 Getting to know your Nortel Business Secure Router 252 NN47923 501 ...
Страница 48: ...48 Chapter 2 Introducing the SMT NN47923 501 SMT menus at a glance Figure 6 SMT overview ...
Страница 72: ...72 Chapter 3 WAN and Dial Backup Setup NN47923 501 ...
Страница 80: ...80 Chapter 4 LAN setup NN47923 501 ...
Страница 84: ...84 Chapter 5 Internet access NN47923 501 ...
Страница 98: ...98 Chapter 6 Remote Node setup NN47923 501 ...
Страница 102: ...102 Chapter 7 IP Static Route Setup NN47923 501 ...
Страница 130: ...130 Chapter 9 Network Address Translation NAT NN47923 501 ...
Страница 156: ...156 Chapter 12 SNMP Configuration NN47923 501 ...
Страница 178: ...178 Chapter 14 System information and diagnosis NN47923 501 ...
Страница 198: ...198 Chapter 15 Firmware and configuration file maintenance NN47923 501 ...
Страница 212: ...212 Chapter 17 Remote Management NN47923 501 ...
Страница 232: ...232 Appendix B Triangle Route NN47923 501 ...
Страница 252: ...252 Appendix D PPPoE NN47923 501 ...
Страница 256: ...256 Appendix E Hardware specifications NN47923 501 ...
Страница 266: ...266 Appendix F IP subnetting NN47923 501 ...
Страница 308: ...308 Appendix H NetBIOS filter commands NN47923 501 ...
Страница 332: ...332 Appendix K Brute force password guessing protection NN47923 501 ...