Appendix B IP Addresses and Subnetting
P-873HNU(P)-51B User’s Guide
296
Figure 176
Network Number and Host ID
How much of the IP address is the network number and how much is the host ID varies according
to the subnet mask.
Subnet Masks
A subnet mask is used to determine which bits are part of the network number, and which bits are
part of the host ID (using a logical AND operation). The term “subnet” is short for “sub-network”.
A subnet mask has 32 bits. If a bit in the subnet mask is a “1” then the corresponding bit in the IP
address is part of the network number. If a bit in the subnet mask is “0” then the corresponding bit
in the IP address is part of the host ID.
The following example shows a subnet mask identifying the network number (in bold text) and host
ID of an IP address (192.168.1.2 in decimal).
By convention, subnet masks always consist of a continuous sequence of ones beginning from the
leftmost bit of the mask, followed by a continuous sequence of zeros, for a total number of 32 bits.
Subnet masks can be referred to by the size of the network number part (the bits with a “1” value).
For example, an “8-bit mask” means that the first 8 bits of the mask are ones and the remaining 24
bits are zeroes.
Table 113
Subnet Masks
1ST OCTET:
(192)
2ND
OCTET:
(168)
3RD
OCTET:
(1)
4TH OCTET
(2)
IP Address (Binary)
11000000
10101000
00000001
00000010
Subnet Mask (Binary)
11111111
11111111
11111111
00000000
Network Number
11000000
10101000
00000001
Host ID
00000010
Содержание P-873HNU-51B
Страница 4: ...Contents Overview P 873HNU P 51B User s Guide 4...
Страница 13: ...Table of Contents P 873HNU P 51B User s Guide 13 Appendix F Legal Information 329 Index 333...
Страница 14: ...Table of Contents P 873HNU P 51B User s Guide 14...
Страница 15: ...15 PART I User s Guide...
Страница 16: ...16...
Страница 32: ...Chapter 2 The Web Configurator P 873HNU P 51B User s Guide 32...
Страница 57: ...57 PART II Technical Reference...
Страница 58: ...58...
Страница 64: ...Chapter 5 Network Map and Status Screens P 873HNU P 51B User s Guide 64...
Страница 108: ...Chapter 7 Wireless P 873HNU P 51B User s Guide 108...
Страница 132: ...Chapter 9 Static Routing P 873HNU P 51B User s Guide 132...
Страница 152: ...Chapter 10 Quality of Service QoS P 873HNU P 51B User s Guide 152...
Страница 168: ...Chapter 11 Network Address Translation NAT P 873HNU P 51B User s Guide 168...
Страница 182: ...Chapter 13 IGMP P 873HNU P 51B User s Guide 182...
Страница 188: ...Chapter 14 Interface Group P 873HNU P 51B User s Guide 188...
Страница 202: ...Chapter 17 Parental Control P 873HNU P 51B User s Guide 202...
Страница 224: ...Chapter 22 Logs P 873HNU P 51B User s Guide 224...
Страница 234: ...Chapter 25 xDSL Statistics P 873HNU P 51B User s Guide 234...
Страница 238: ...Chapter 26 Users Configuration P 873HNU P 51B User s Guide 238...
Страница 244: ...Chapter 27 Remote Management P 873HNU P 51B User s Guide 244...
Страница 250: ...Chapter 29 Logs Setting P 873HNU P 51B User s Guide 250...
Страница 256: ...Chapter 31 Configuration P 873HNU P 51B User s Guide 256...
Страница 262: ...Chapter 32 Diagnostic P 873HNU P 51B User s Guide 262...
Страница 274: ...Chapter 34 Product Specifications P 873HNU P 51B User s Guide 274...
Страница 310: ...Appendix C Pop up Windows JavaScript and Java Permissions P 873HNU P 51B User s Guide 310...
Страница 324: ...Appendix D Wireless LANs P 873HNU P 51B User s Guide 324...