Echelon i.LON 600 LonWorks/IP Server - Manual (Page 97)

Section 3: Appendixes
something changes, the Configuration Server will update all i.LONs in the
L
ON W ORKS /IP channel.
Do not rely on DNS to resolve i.LON IP addresses. Use static addresses that do not
change.
Dynamic DNS
If your ISP does not offer a static IP address service, and you still want Internet access to
an i.LON at your house, you can use a third party solution called dynamic DNS (DDNS).
Providers include dns2go.com, dyndns.org and others. Perform a quick Internet search on
“dynamic DNS”.
How DDNS Works
DDNS operators rely on the fact that your home’s IP address does not frequently change.
Depending on your ISP, the home address may change only when you power cycle the
NAT gateway. If the NAT gateway is on 24/7, it may be months before your home’s
address changes. It is also possible that your ISP forces the address to change even if the
gateway is not power cycled. The amount of time that a device may keep its address is
called its “lease”. DHCP servers lease an address for a period of time after which the
lessee is supposed to go back and acquire another lease.
When using DDNS, each time a new DHCP lease is given (e.g. each time the PC’s IP
address changes) the DDNS server is notified. The DDNS server keeps track of each
client’s current address. To let external users see the web server in your home, instead of
telling the registrar that www.myhouse.com is linked to 131.23.203.17, you tell the
registrar that www.myhouse.com is linked to myhouse.ddns.org (for example). When an
Internet user types in www.myhouse.com, the Internet DNS server forwards the request
to myhouse.ddns.org, which forwards the request to the current IP address of your home.
The DDNS provider tracks any changes in your home’s address and maps/forwards any
request for myhouse.ddns.org to your house’s current IP address.
Because of its potential complications and its reliance on relatively small third party
providers, we do not recommend using DDNS when constructing L
ON W ORKS /IP
channels.
*Check the terms of service agreement with your ISP before using DDNS. Some ISPs
restrict using these services.
i.LON 600 User’s Guide 89