Initial Assignment Of An Ipv4 Address; Address Assignment Via Dhcpv4 - Siemens SIMATIC NET SCALANCE W780 Series Configuration Manual

IP addresses
5.2 IPv4 address
Outside the local area network, the distinction between network ID and host ID is of no
significance, in this case packets are delivered based on the entire IP address.
Note
In the bit representation of the subnet mask, the "ones" must be set left-justified; in other
words, there must be no "zeros" between the "ones".
5.2.2

Initial assignment of an IPv4 address

Configuration options
An initial IP address for a SCALANCE W device cannot be assigned using Web Based
Management (WBM) or the Command Line Interface (CLI) over Telnet because these
configuration tools require that an IP address already exists.
The following options are available to assign an IP address to an unconfigured device
currently without an IP address:
● DHCP (default)
● Primary Setup Tool
● STEP 7
● NCM PC
Note
When the product ships and following "Restore Memory Defaults and Restart", DHCP is
enabled. If a DHCP server is available in the local area network, and this responds to the
DHCP request of a SCALANCE W700, the IP address, subnet mask and gateway are
assigned automatically when the device first starts up. "Restore Factory Defaults and
Restart" does not delete an IP address assigned either by DHCP or by the user.
5.2.3

Address assignment via DHCPv4

Properties of DHCP
DHCP (Dynamic Host Configuration Protocol) is a method for automatic assignment of IP
addresses. It has the following characteristics:
● DHCP can be used both when starting up a device and during ongoing operation.
● The assigned IP address remains valid only for a limited time known as the lease time.
When half the period of validity has elapsed. the DHCP client can extend the period of
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SCALANCE W780/W740 to IEEE 802.11n Web Based Management
Configuration Manual, 08/2018, C79000-G8976-C267-13