Sierra Wireless 2170042 - Manual (Page 4)

Rev A Dec.08 4
• .com is the TLD
• mydomain is the domain (usually noted as
mydomain.com since the domain is specific to the TLD)
• car54 is the subdomain or server name associated with the
device, computer, or modem registered with
mydomain.com
car54.mydomain.com.ca
This would be the same as above, but with the addition of the
country code. In this example, the country code (.ca) is for
Canada.
A URL (Universal Resource Locator) is different from a
domain name in that it also indicates information on the proto‐
col used by a web browser to contact that address, such as
http://www.sierrawireless.com. www.sierrawireless.com is a
fully qualified domain name, but the http://, the protocol iden‐
tifier, is what makes the whole thing a URL.
Dynamic Names
When an IP address is not expected to change, the DNS server
can indicate to all queries that the address can be cached and
not looked up for a long period of time. Dynamic DNS
servers, conversely, have a short caching period for the
domain information to prevent other Internet sites or queries
from using the old information. Since the IP address of a
modem with a dynamic account can change frequently, if the
old information was used (such as with a DNS server which
indicates the address can be cached for a long period of time)
when the IP address changed, the domain would no longer
point to the new and correct IP address of the modem.
If your modem is configured for Dynamic IP, when it first
connects to the Internet, it sends a IP change notification to IP
Manager. IP Manger will acknowledge the change and update
the Dynamic DNS server. The new IP address will then be the
address for your modem’s configured name.
Once your modem’s IP address has been updated in IP
Manager, it can be contacted via name. If the IP address is
needed, you can use the domain name to determine the IP
address.
Note: The fully qualified domain name of your modem will be a
subdomain of the domain used by the IP Manager server.