NEC Electra Elite IPK II System User Manual page 1103

Electra Elite IPK II
With a Global IP Address, connected equipment can be accessed through the internet, so each address
must be unique. To avoid a conflict, the addresses are controlled by ARIN (American Registry for
Internet Numbers). To obtain a Global IP Address, contact ARIN or apply with your local internet service
provider (ISP).
The first of three groups of numbers (depending on the subnet mask) identifies the network on which
your computer is located. The remaining group(s) of numbers identify your computer on that network.
Subnet Mask
As the IP Address includes information to identify both the network and the final destination, the Subnet
Mask is used to set apart the network and destination information.
The default subnet masks are:
In the above table, the Subnet Mask contains four groups of numbers. When a group contains the
number 255, this tells the router to ignore or mask that group of numbers in the IP address as it is
defining the network location of the final destination. So, for example, if the IP Address were:
172.16.0.10 and the Subnet Mask used was Class B (255.255.0.0), the first two groups of numbers
(172.16) are ignored after they reach the proper network location. The next two groups (0.10) are the
final destination in the LAN to which the connection is to be made.
DHCP
DHCP (Dynamic Host Configuration Protocol) assigns a dynamic IP Address. Network control may be
easier with DHCP as there is no need to assign and program individual IP Addresses for the LAN
equipment. To use a dynamic IP Address, a DHCP server must be provided. The Electra Elite IPK II
system allows using DHCP.
When equipment connected to the LAN (the DHCP client) is requesting an IP Address, it searches the
DHCP server. When the request for an address is recognized, the DHCP server assigns an IP Address,
Subnet definition, and the IP Address of the router, etc., based on the system programming.
The IPK II CPUII must always have a static IP address. This address is set in Program 10-12-01 : CPUII

Network Setup – IP Address (default: 172.16.0.10).
Voice Over Internet Protocol (VoIP)
Class Default Subnet Mask
A
B
C
255.0.0.0
255.255.0.0
255.255.255.0
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