DDNS stands for Dynamic Domain Name Systems that allow you to associate your dynamic changed public IP with a domain host name. DDNS allow you to access your home/office computer that serve as ftp service, remote desktop, email and webiste by referring the the domain host name.
The most famous ddns provider is DynDNS but unfortunately Dyn will discontinue their free dynamic DNS account on 7 May 2014.
Normally the user who use the dynamic DNS is the the home user or small business that might not afford for the paid ddns service. Therefore, below are some of alternate free DDNS to replace dyndns
Afraid.org
URL: http://freedns.afraid.org/
Free hostnames for DDNS: 5
Review: Provide free DNS hosting as well that allow you to configure static and dynamic DNS record under your own domain name. Support most of the open source router such as DD-WRT, OpenWRT, pfSense. Provided with Windows and Linux dynamic DNS update client.
DNS Exit
Free hostnames for DDNS: (not specify)
Review: Provide free DNS hosting that allow to configure static and dynamic DNS record under your own domain name. Provided with Windows and Linux update client
Duck DNS
URL: http://duckdns.org/
Free hostnames for DDNS: (not specify)
Review: Allow to sign-in using Facebook, Reddit and Google account. Provide with multiple ddns update method in http://duckdns.org/install.jsp
No-IP
Free hostnames for DDNS: 3
Review: Provide Dynamic DNS Update Client for Windows. Easily to setup and configure.
Remark: Not recommended because it require for web login every 30 days in order to keep your account active
Other free alternative dynamic DNS provider
| DNSdynamic | http://www.dnsdynamic.org/ |
| Change IP | http://www.changeip.com/ |
| ZoneEdit | http://www.zoneedit.com/ |
| Zonomi | http://www.zonomi.com/ |
| CJB | http://www.cjb.net/ |
| 3322 | http://www.3322.org/ |
| DHIS | http://www.dhis.org/ |
| DNS Made Easy | http://www.dnsmadeeasy.com/ |
| DynDNS.dk | http://dyndns.dk/ |