User`s manual

User’s Manual 99
C.2.3 Dynamically Assigned Internet Addresses
In many instances, there are no 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 Configu-
ration Protocol (DHCP). The RCM3400 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 private address can
be used to perform some Internet tasks such as sending e-mail or browsing the Web, but
usually cannot be used 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 private IP addresses that are assigned using DHCP. When your com-
puter 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 RCM3400 from the Internet, you can place
the RCM3400 on the internal network using a private address assigned either statically or
through DHCP.