DDNS – Free Dynamic DNS Providers

We maintain the list of Dynamic DNS (DDNS) providers online. Dynamic DNS is a method that allows you to notify a Domain Name Server (DNS) to change in your active DNS configuration on a device such as a router or computer of its configured hostname and address. It is most useful when your computer or network obtains a new IP address lease and you would like to dynamically associate a hostname with that address, without having to manually enter the change every time. Since there are situations where an IP address can change, it helps to have a way of automatically updating hostnames that point to the new address every time. Enter DDNS to the rescue.
We are proud to be considered the top resource online for information on dynamic dns providers. This is a gentle, not-too-technical introduction on it, how it works, and a comprehensive list of mostly free providers. We have also provided some dynamic dns reviews on various hosting companies to help you better decide who to choose!

If you like this list, please link to it will help others find this free list more easily!

Name	URL and domain selection	Subdomains?	Domains?
dnsdynamic.org (June 2011)	http://www.dnsdynamic.org/ Domains: *.user32.com, *.tftpd.net, *.wow64, etc (12+) Free VPN Also Available	Free	Free
changeIP.com (June 2011)	http://www.changeip.com/ Domains: *.dumb1.com, *.wikababa.com, *.dynamic-dns.net, etc (100+)	Free	$3/mo $6/qr $15/yr
No IP (June 2011)	http://www.no-ip.com/ Domains: *.no-ip.com, *.servequake.com, *.sytes.net, etc. (21 domains)	Free (5 domain limit)	$15/yr
afraid.org (June 2011)	http://freedns.afraid.org/ Domains: *.afraid.org, many many others (they list about 300. no, really.)	Free (donations encouraged)	Free (donations encouraged)
dyndns.com (December 2011)	http://www.dyndns.com/ 18 Subdomains Available	No Longer Free	Free (Pro: $15/yr)
zonomi.com (June 2011)	http://www.zonomi.com/	Free	$10/yr
zoneedit.com (June 2011)	http://www.zoneedit.com/	Free	Free
cjb.net (June 2011)	http://www.cjb.net/ Domains: *.cjb.net	Free	N/A
Zerigo (June 2011)	http://www.zerigo.com/managed-dns	Free (Pro: $19/yr)	Free
3322.org (June 2011)	http://www.3322.org/ Chinese Domains: *.3322.org, *.8866.net, etc (quite a few, but seem to have trouble accessing their sites from US)	Free	N/A
oray.com (June 2011)	http://www.oray.com/ Chinese Domains: *.xicp.net, etc (in Chinese)	Free	N/A
DarSite (June 2011)	http://www.darsite.com/eng Domains: *.darweb.com	$100/year	$100/year
ddns.nu (5 Dec 2001)	http://www.ddns.nu/ Domains: *.cable.nu, *.optus.nu, *.evangelion.nu, several others	Reg Disabled	Reg Disabled
Deerfield (2 Nov 2002)	http://dns2go.deerfield.com/ Domains: *.dns2go.com, *.idleplay.net, *.dynamic-site.net, others	$9.95/year	$19.95/year
DHIS (June 2011)	http://www.dhis.org/ Domains: *.net.dhis.org	Free	N/A
DHS (9 Dec 2001)	http://www.dhs.org/ Domains: *.dhs.org	$5 (one-time charge?)	N/A
DNS 4 BIZ (2 Nov 2002)	http://www.dns4biz.de/ Domains: Unknown	Free (also for-pay options available)	$4.99/month
DNS Exit (2 Dec 2002)	http://www.dnsexit.com/	N/A	Free
DNS Made Easy (2 Nov 2002)	http://www.dnsmadeeasy.com/ Domains: *.dnsmadeeasy.com, others	Free	$4.95/year (up to 5 domains)
DNS Park (8 Dec 2005)	http://www.dnspark.com/services/dynamicDNS.php	N/A	$8.95/year
dnsd.be (5 Dec 2001)	http://www.dnsd.be/ Domains: *.dnsd.be	5 Euro per year for the first hostname; 4 Euro for additional hostnames mapped to the same IP.	N/A
DtDNS (9 Dec 2001)	http://www.dtdns.com/ Domains: *.darktech.org, *.dtdns.net, *.etowns.com, others	Free	$20/year
dyn.ee (9 Dec 2001)	http://www.dyn.ee/ Domains: *.dyn.ee, *.dynserv.[com/net/org]	Free	N/A
DynAccess (5 Dec 2001)	http://www.dynaccess.de Domains: *.dyn-access.(com/net/org/de/info/biz), several others	5 Euro/year (or more, depending on name selected)
DynamIP (5 Dec 2001)	http://www.dynamip.com/	N/A	$3/month
Dynamx (5 Dec 2001)	http://www.dyn.ro/ Domains: *.dynam.ac, *.dyn.ro, *.my-ho.st, *.irc-chat.org	Free	N/A
dyndns.dk (9 Dec 2001)	http://dyndns.dk/ Domains: *.dyndns.dk, *.kyed.com, *.lir.dk, *.yaboo.dk	Free	$10/year
dyndsl.com (5 Dec 2001)	http://www.dyndsl.com/ Domains: *.dyndsl.com, *.45z.com, *.au2000.com	Free	N/A
dynip.com (9 Dec 2001)	http://www.dynip.com/ Domains: *.dynip.com, others	$35.95/year and up (based on domain name chosen)	$159.95/year
dyns.cx (5 Dec 2001)	http://dyns.cx/ Domains: *.dyns.cx, *.dyns.net, *metadns.cx, others	Free	15 Euro/year
DynUp (5 Dec 2001)	http://www.dynup.net/ Domains: *.dynup.net	Free	N/A (“coming soon”)
Easy DNS (5 Dec 2001)	https://web.easydns.com/	N/A	$19.95/year
Home PC (5 Dec 2001)	http://www.homepc.org/ Domains: *.homepc.org	Reg Disabled	N/A
Hotline DNS (5 Dec 2001)	http://www.hldns.com/ Domains: *.hldns.com	Free	N/A
Microtech Ltd. (5 Dec 2001)	http://www.microtech.co.gg/dns/ Domains: *.freelancedeveloper.com, *.ohflip.com, *.microtech.co.gg, *.easydns4u.com	Free	20 UKP/year
MiniDNS (5 Dec 2001)	http://www.minidns.net/ Domains: *.minidns.net	Free (“with quota”)	Free (“with quota”)
myserver.org (9 Dec 2001)	http://www.myserver.org/ Domains: *.myserver.org, *.USArmyReserve.com, *.WidescreenHD.tv, several others	Free	$24.95/year
Nettica (2 Nov 2002)	http://www.nettica.com/	N/A	$25/year, $45 for 2 years
Open Domain Server (5 Dec 2001)	http://www.ods.org/ Domains: *.ods.org	Free	$20/year for up to 5 domains
Planet DNS (9 Dec 2001)	http://www.planetdns.net/ Domains: *.planetdns.[net/org/biz/ca]	$19.95/year	$49.95/year
PowerDNS (5 Dec 2001)	http://www.powerdns.com/	N/A	Free for up to five domains, per email from site admin.
Prout (2 Nov 2002)	http://www.prout.be/dns/ Domains: *.prout.be, *.dyn.prout.be	Free	N/A
Sitelutions (2 Nov 2002)	http://www.sitelutions.com/info/sldns	N/A	Free
Static Cling (5 Dec 2001)	http://www.staticcling.org/ Domains: *.staticcling.org	Free	N/A
That IP (2 Nov 2002)	http://www.thatip.com/ Domains: *.thatip.com	$10 for up to 5 names	$10 for up to 5 names
Turnkey Hub (June 2011)	https://hub.turnkeylinux.org/ Domains *. TKLAPP.com Cloud Services with Turnkey Hub, but pricing based on Amazon EC3	Free	Free
TZO Internet (5 Dec 2001)	http://www.tzo.com/ Domains: *.tzo.com, *.tzo.net, *.tzo.org, *.tzo.cc	$24.95/year	$59.95/year $99.95/2 years
whyI (9 Dec 2001)	http://www.whyi.org/ Domains: *.yi.org,*.whyi.org,*.weedns.com,*.b0b.org	Free	N/A
Xname (June 2011)	http://www.xname.org/ Domains: *.xname.org	Free	N/A
Widge DNS (3 Dec 2002)	http://dns.widge.net/	N/A	Free
World Wide DNS (5 Dec 2001)	http://www.worldwidedns.net/	N/A	$39/year

Choosing Between Wireless and Wired Home Security System

There are many types of security devices that can be used as per an individual’s requirements. The primary classification for security systems is the wired and wireless category. Most devices in the security systems come with wired as well as wireless models. Both have their own advantages and disadvantages. Let us understand some basic differences that will help you to decide in favour of wireless or wired home security systems.

Differences between Wireless and Wired Home Security Systems

The most obvious and the biggest difference in both systems is that of wires. However, it is not as easy as it appears. The presence or absence of wires in a security difference makes changes in its installation, maintenance, hardware and software. Wired systems involve running a wire from the control panel individually to all the components of the security system.
Wired home security systems need an expertise in installation. A number of holes need to be drilled and a bunch of wires need adjustment without damaging the electric wires and the plumbing lines. It is best to make a pre-wiring plan when your house is still under construction. Other than additional wiring, make extra electric sockets at places that might need protection like doors, windows, staircases, etc. Install electric sockets outside your house as well.
In case, you are buying an already constructed house, it is best to take the help of a professional. You can call an electrician to do the wiring or take help from a handyman if your DIY skills can be applied. However, do not cause additional damage to your wirings in an over enthusiasm to install the system yourself. Also, opt for wired systems if you are engaging a dealer to do the job as they will in any case charge installation fees.
On the cost front, wired systems win hands down as the components are cheaper. However, installation is a very labour intensive process and needs sufficient expertise. The cost of installation is generally very high in these systems. Add to this the additional cost incurred if anything goes wrong during the wiring process. Wireless components are expensive but you can save by installing them yourself.
Wired systems are easy to maintain and easy to expand. Updating and upgrading is also easier in case of wired security systems. Wireless systems are generally restricted in terms of maintenance and become obsolete faster but they offer the latest in terms of technology. Wireless systems, though easy to install, are generally bigger in size and need to be constantly monitored for batteries.
However, is you want to have a less intrusive addition to neatly fit into your home decor, wireless devices are the best option for you. Owners of antique homes might also prefer wireless system to prevent any damage to the property. Wireless systems are also good for areas where wiring cannot be fitted easily like the lawn or external gates.
Both systems have their own advantages and disadvantages. Some people use a combination of wired and wireless devices to take the best out of both.

CS Vs C Mount Cameras

Modern cameras and lenses are generally CS mount rather than C mount. With CS mount cameras both types of lenses can be used but the C mount lens requires a 5mm ring (VM400) to be fitted between the camera and lens to achieve a focused image. With C mount cameras it is not possible to use CS mount lenses as it is not physically possible to mount the lens close enough to the CCD to achieve a focused image.

C Vs CS Mount Lens

 
The physical difference is the CS mount lens is designed to be mounted ~5mm closer to the image sensor than a C mount lens. (C-mount lenses are designed to be mounted 17.526mm in front of the image sensor vs. 12.5mm for CS-mount.) You can always use a C mount lens on a CS mount camera by using a 5mm spacer ring (many cameras now have C/CS selectable adjustment screws or rings). You can never use a CS mount lens on an older style C mount camera unless you are willing to physically modify the camera. Cost wise the CS mount lens is much less expensive since it uses fewer glass elements. Quality of image is the same. C mounts are becoming less and less popular and are generally only used on the more telephoto focal lengths such as 25, 50 and 75mm, and bigger zooms.

 
Both the C and CS mount are 1 inch wide (25.4mm) with 32 threads per inch (0.03125 inches or 0.79375mm). This dimension comes in handy if you need to insert a spacer to obtain proper focus. Unscrew the lens (or unscrew the camera from the mount in the case of telescope use and count the turns until proper focus is obtained. Multiply the above dimension by the number of turns to obtain the needed spacer or washer. (Washers are sometimes used as spacers if there are enough threads available.) Example: 1.25 turns x 0.79 mm = 0.9875 or ~1 mm. Many cameras (especially newer ones) have set screws to allow small adjustments in the distance between the lens and the image sensor.

Troubleshooting

A lot of the time when someone is using a CS mount security camera they will sometimes get a fuzzy picture and not be able to focus the image properly. If you look at what we have discussed so far you can probably figure out a possible solution to this. The most common mistake people make is that they will mount their CS mount lens onto their security camera while the 5mm ring is still attached. This ring is only useful if you are using a C mount lens. By simply removing this ring they will allow the CS lens to get close enough to the CCD chip to obtain a proper focus.
By taking the time to understand these differences in mounting for C and CS mount cameras and lenses you will help prevent damages to your surveillance equipment and reduce your workload.