Figure 33 Ip Addressing: Class C; Figure 34 Subnet Mask: Class C - Nortel DMS-100 User Manual

156 Appendix E: Understanding IP and IP addressing

Figure 33 IP addressing: class C

Class C addresses range from 192.0.0.X to 223.255.255.X (standard network mask is 255.255.255.0),
therefore, we can have 16384-2 class C networks each with 65536-2 hosts (if no subnets).
|
110
| 3 bit |
Class C indicator
For any class, the hostid can be split into a subnet id and a hostid depending on custom-
er requirements. This helps simplify routing to areas. For class C network, the subnet id
can range from 2 to 6 bits.
Note 1: Network ids and host ids which are comprised of all 1's or all 0's are reserved,
therefore, subtract 2 from the subnet id and hostid to get the actual count.
Note 2: There are also special addresses that are reserved for 'unconnected' networks
(networks that use IP but are not connected to the Internet). Class C networks
have 256 of these special addresses ranging from 192.168.0.0 to 192.168.255.0.

Figure 34 Subnet mask: class C

No. subnets No. hosts
2 62
6 30
14 14
30 6
62 2
297-8991-910 Standard 03.01 August 1999
networkid
21
bits
Field subnet in table IPNETWRK
CLASS C subnet masks
netmask
255.255.255.192
255.255.255.224
255.255.255.240
255.255.255.248
255.255.255.252
Host/Router
|
subnet id
2 to 6 bits
|
Netmask in binary format
(11111111.11111111.11111111.11000000)
(11111111.11111111.11111111.11100000)
(11111111.11111111.11111111.11110000)
(11111111.11111111.11111111.11111000)
(11111111.11111111.11111111.11111100)
Base_Tel-13
32
bits
|
hostid
8 bits
|
hostid
2 to 6 bits
|
|
Base_Tel-14
IPNETWRK
subnet size
DMS
2
3
4
5
6