ELSA LANCOM Business 6000, Руководство пользователя

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Technical basics
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ELSA LANCOM Business 6000
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116
EN
A new notation of the netmask simply attaches the number of bits available
for the network address to the IP address: 137.226.4.101/24. The number
after the slash tells us that the first 24 bits indicate the network address. This
notation reduces the length of the entries in the routing tables.
IP address
administration The IP addresses must be unique within a specific network in order to avoid
confusion. Since the Internet is based on TCP/IP and thus uses IP addresses
for its millions of connected computers, all Internet addresses must also be
unique. Bodies exist that manage and distribute these publicly-accessible
addresses. Since the number of IP addresses theoretically available is
limited, these distributing bodies charge high rates for the addresses.
Private Address
Spaces
A range of IP addresses are reserved for use free of charge (private address
spaces) so that companies do not have to purchase individual IP addresses
for every workstation. In a closed network, these addresses can be used as
desired, in a private network or company, for example. The same address can
be used in other closed networks (e.g. in different companies), but the
addresses within one network must be unique.
However, these reserved IP addresses must not be made public (on the
Internet). Only those devices in a network that are connected to a public
network (e.g. the router at the interface to the Internet) must have a
registered IP address.
The allocation of IP addresses by the IANA ( I nternet A ssigned N umbers
A uthority) permits the following address ranges to be used for private use:
IP addresses
Network
mask
Comment
10.0.0.0 255.0.0.0 “10” networks: All IP addresses beginning with 10. and whose mask begins with
255. belong to the address range reserved for private use.
172.16.0.0 255.240.0.0 All IP addresses beginning with 172.16.–172.31. which are associated with a net
mask greater than or equal to 255.240.0.0 are within the address range reserved
for private networks.
192.168.0.0 255.255.0.0 All IP addresses beginning with 192.168. and whose mask begins with 255.255.
belong to the address range reserved for private use.
224.0.0.0 224.0.0.0 All IP addresses beginning with a 224 which are associated with a net mask also
beginning with 224 are within the reserved address range.
This range is reserved for broadcasting purposes and should not be used for pri-
vate networks.