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Nortel Business Secure Router 222 Configuration — Advanced
Appendix G
IP subnetting
IP addressing
Routers route based on the network number. The router that delivers the data
packet to the correct destination host uses the host ID.
IP classes
An IP address is made up of four octets (eight bits), written in dotted decimal
notation, for example, 192.168.1.1. IP addresses are categorized into different
classes. The class of an address depends on the value of its first octet.
•
Class A addresses have a 0 in the left-most bit. In a class A address, the first
octet is the network number and the remaining three octets make up the host
ID.
•
Class B addresses have a 1 in the left-most bit and a 0 in the next left most bit.
In a class B address, the first two octets make up the network number and the
two remaining octets make up the host ID.
•
Class C addresses begin (starting from the left) with 1 1 0. In a class C
address, the first three octets make up the network number and the last octet is
the host ID.
•
Class D addresses begin with 1 1 1 0. Class D addresses are used for
multicasting. (There is also a class “E” address, which is reserved for future
use.)
Содержание 222
Страница 14: ...14 Contents NN47922 501 ...
Страница 24: ...24 Tables NN47922 501 ...
Страница 30: ...30 Preface NN47922 501 ...
Страница 46: ...46 Chapter 2 Introducing the SMT NN47922 501 SMT menus at a glance Figure 6 SMT overview ...
Страница 70: ...70 Chapter 3 WAN and Dial Backup Setup NN47922 501 ...
Страница 78: ...78 Chapter 4 LAN setup NN47922 501 ...
Страница 100: ...100 Chapter 6 Remote Node setup NN47922 501 ...
Страница 104: ...104 Chapter 7 IP Static Route Setup NN47922 501 ...
Страница 132: ...132 Chapter 9 Network Address Translation NAT NN47922 501 ...
Страница 154: ...154 Chapter 11 Filter configuration NN47922 501 ...
Страница 158: ...158 Chapter 12 SNMP Configuration NN47922 501 ...
Страница 198: ...198 Chapter 15 Firmware and configuration file maintenance NN47922 501 ...
Страница 212: ...212 Chapter 17 Remote Management NN47922 501 ...
Страница 232: ...232 Appendix B Triangle Route NN47922 501 ...
Страница 252: ...252 Appendix D PPPoE NN47922 501 ...
Страница 260: ...260 Appendix F Hardware specifications NN47922 501 ...
Страница 270: ...270 Appendix G IP subnetting NN47922 501 ...
Страница 308: ...308 Appendix H Command Interpreter NN47922 501 ...
Страница 312: ...312 Appendix I NetBIOS filter commands NN47922 501 ...
Страница 336: ...336 Appendix L Brute force password guessing protection NN47922 501 ...