Pilz PSSnet SHL 8T MRP - Manual (Page 31)

Entering the IP Parameters
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2.1 IP Parameter Basics
PSSnet SHL - Basic Configuration
Pilz GmbH & Co. KG, Felix- Wankel Str. 2, 73760 Ostfildern
Since 1993, RFC 1519 has been using Classless Inter Domain Routing
(CIDR) to provide a solution to get around these problems. CIDR overcomes
these class boundaries and supports classless address ranges.
With CIDR, you enter the number of bits that designate the IP address range.
You represent the IP address range in binary form and count the mask bits
that designate the netmask. The netmask indicates the number of bits that
are identical to the network part for all IP addresses in a given address range.
Example:
The combination of a number of class C address ranges is known as “super-
netting”. This enables you to subdivide class B address ranges to a very fine
degree.
IP address, decimal
149.218.112.1
149.218.112.127
CIDR notation: 149.218.112.0/25
Mask bits
Network mask,
decimal
255.255.255.128
IP address, hexadecimal
10010101 11011010 01110000 00000001
10010101 11011010 01110000 01111111
25 mask bits