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Nortel Business Secure Router 252 Configuration — Advanced
Appendix F
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 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 ...