Dynamic Names - Sierra Wireless AirLink ES440 User Manual

ALEOS 4.4.0 Software Configuration User Guide
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the domain, but do not need to be registered with ICANN or any other
registry. It is the responsibility of a domain to keep track of its own subs.
car54.mydomain.com
• .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 device 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.
Tip: A URL (Universal Resource Locator) is different from a domain name in that it also
provides information on the protocol used by a web browser to contact that address such
as http://www.sierrawireless.com
domain name, but http://, the protocol identifier, 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 device with a dynamic account can change
frequently, if the old information was used (e.g., 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 device.
If your AirLink device is configured for Dynamic IP when it first connects to the
Internet, it sends an IP change notification to the IP Manager. The IP Manager
acknowledges the change and updates the Dynamic DNS server. The new IP
address will then be the address for your device's configured name.
When your device IP address has been updated in IP Manager, it can be
contacted by name. If the IP address is needed, use the domain name to
determine the IP address.
Note: The fully qualified domain name of your AirLink device will be a subdomain of the
domain used by the IP Manager server.
. www.sierrawireless.com is a fully qualified
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