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Related to DDNS: DynDNS


(Dynamic DNS) A service that lets anyone on the Internet gain access to resources on a local network when the Internet address of that network is constantly changing. Such resources are typically a Web server, Webcam or a PC for remote control operation.

Cable and DSL providers frequently change the IP address of their customer's service, which makes it impossible to access the network from the outside world without knowing what the IP address is at any given moment. DDNS client software resides in a router, Webcam or PC. When it detects that the IP address of the cable or DSL modem has changed, it notifies the DDNS service provider of the new address. See dynamic IP address.

The DDNS Service Provider
The key element in this is the DDNS service provider, which hosts the DNS servers that become the authority for the domain names. When the DNS server responds to a request for the IP address of a domain name, it returns the current address along with a time-to-live (TTL) of only a few minutes. By causing the address to expire in such a short time, it prevents the address from being cached throughout the Internet. See TTL.

The DDNS provider generally offers a faster and more economical way to gain external access to internal resources than by upgrading ISP service from dynamic addressing to a static address. The largest DDNS provider is Dynamic Network Services, which acquired DDNS company Tzolkin Corporation in 2012 (www.dyn.com). See DDNS relay, DHCP, WINS and DNS.

Comes With the Product
For residential users of Foscam's IP network cameras, the company offers its own DDNS service to allow remote access to the camera. As in this example, a DDNS URL is assigned to a new user in case the Internet provider changes the IP address.
References in periodicals archive ?
Cyberoam DDNS service is of critical need to enterprises functioning without a static IP address through hosted web servers.
UGate-3300 - Cable/xDSL Internet Wireless Sharing Gateway with DDNS and built-in Print Server -- UGate-3200P - Cable/xDSL 7-port Internet Sharing Gateway with DDNS and built-in Print Server -- UGate-3200 - Cable/xDSL Internet Sharing Gateway with 10/100M 7-port Hub and DDNS -- UGate-3000 - Cable/xDSL Internet Sharing Gateway with 10/100M 4-port Hub and DDNS
Features - CMOS Sensor with Glass Lens - Dual -- Codec MPEG-4 or MJPEG Selectable Compression - Capture Video and Audio (with Built-In Microphone) to an external Hard Drive - Built-In Web Server for Remote Access with On-Screen Users Connected Information - Supports UPnP for Easy Discovery on the Network - DDNS support Linksys SoloLink(TM)*and Other Available Free DDNS Services - Supports up to 10 Simultaneous Users - Included Software for Monitoring and Recording Up to 9 Cameras Simultaneously - Email Alerts to up to 4 Email addresses with Video Clips upon Motion Detection - LCD Screen on Camera Displays Full IP Address *SoloLink(TM) Dynamic Domain Name System (DDNS) Service
The unit's DDNS support allows a user to register a specific domain name for the host computer so authorized outside users can access using a simple, standard URL address instead of a complex, ever-shifting numerical IP address.
Net DDNS Service, which will allow the UGate 3000 to work with single or multiple Private Domain Names.
1 Enhanced, adding significant features such as DDNS, a streamlined Web GUI and a comprehensive suite of easy-to-use configuration and management wizards.
Since 1992, Newbridge Networks has installed networking equipment in more than 150 public DDNs throughout the People's Republic of China, the first of which was in the city of Shanghai.