Adresses examples:
11.10.200.1----------------------A class: NetID=11 & HostID= 10.200.11 (from 0 to 127)
Subnet mask: 255.0.0.0
Subnet mask: 255.255.0.0
Subnet mask: 255.255.255.0
150.214.53.127------------------B class: NetID=150.214 & HostID=53.127 (from 128 to 191)
192.168.13.102------------------C class: NetID=192.168.13 & HostID=102 (from 192 to 223)
BASIC NOTIONS ABOUT IP PROTOCOL
IP protocol is a software protocol which has not connection with network hardware (the main
feature for network interlink).
This protocol allows the network interlink independently from the hardware. IP addresses are
32 bit and divided in 2 fields: IP network identification and Host identification (from this network).
IP adresses are represented in decimal format (4 octos separated by decimal dot) instead of to
express as 32 bit number. Therefore, we can identify easily the octets which belong to network
and host id.
There are special adresses that must not be assigned to a host due to they have an own purpose:
- Network addresses: The network have their own address (NetID) with the network
ID and HostID to 0. Example: 150.214.0.0
- Broadcast addresses: They define the broadcast address to IP level. It consists in
the NetID with the network ID where the broasdcast will be made and in the HostID
all values goint to “1". Example: 150.214.255.255
- Loopback address: They are A class addresses, 127.X.X.>X that has been reserved
to support broadcast between applications of the same host and to check their
operation without interfer with then. B default the loppback address used is
127.0.0.1
- Multicast address: They are D class address and it is not allows to use them for
unicast addresses.
NetID is made with the bits to "1" of the Subnet mask
HostD is made with the bits to "0" of the Subnet mask
USER MANUAL
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