Rabbit RabbitCore RCM4000, User Manual

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User’s Manual 69
6.2.3 Dynamically Assigned Internet Addresses
In many instances, devices on a network do not have fixed IP addresses. This is the case
when, for example, you are assigned an IP address dynamically by your dial-up Internet
service provider (ISP) or when you have a device that provides your IP addresses using
the Dynamic Host Configuration Protocol (DHCP). The RCM4000 modules can use such
IP addresses to send and receive packets on the Internet, but you must take into account
that this IP address may only be valid for the duration of the call or for a period of time,
and could be a private IP address that is not directly accessible to others on the Internet.
These addresses can be used to perform some Internet tasks such as sending e-mail or
browsing the Web, but it is more difficult to participate in conversations that originate
elsewhere on the Internet. If you want to find out this dynamically assigned IP address,
under Windows 98 you can run the
winipcfg
program while you are connected and look
at the interface used to connect to the Internet.
Many networks use IP addresses that are assigned using DHCP. When your computer
comes up, and periodically after that, it requests its networking information from a DHCP
server. The DHCP server may try to give you the same address each time, but a fixed IP
address is usually not guaranteed.
If you are not concerned about accessing the RCM4000 from the Internet, you can place
the RCM4000 on the internal network using an IP address assigned either statically or
through DHCP.