Four types of special IP addresses

1. Direct broadcast address: X.X.X.255 (the last bit of ip is 255)

two。 Restricted broadcast address: 255.255.255.255 (all four bits are 255)

This subnet network has only one IP address, which represents the host.

In terms of routing, it is a full match. Only one ip can be matched.

3. Specific host on this network: 0.0.0.X (X means to take at random between 1 and 254)

4. Loopback address: 127.0.0.1 (belongs to Class An ip address)

The mask is used to identify which bits in an IP address are network bits and which are host bits.

The mask used in ACL is to identify the bits that need to be matched and those bits that do not need to be matched. 255.255.255.255 all need to match.

Reference article:

Bind multiple IP addresses to a single network card in linux system

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