Design and Implementation of a Self-Adaptable Networked DVR

• Main Authors: Cho-li Weng, 翁卓立
• Other Authors: H.-L. Chen
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/57252864829304920168

碩士 === 國立臺灣科技大學 === 電子工程系 === 98 === DVR (Digital Video Recorder) is one of the major products in surveillance industry. In addition to using hard disk as storage media, the major difference between DVR and conventional recording system is the application of network protocol. It also provides the possibility of remote monitoring. No matter how many network protocols have been used in DVR products, it is for sure that some problems will occur during development. This thesis mentions a serious problem DVR could meet if it integrates DDNS function. When DVR is located in a LAN environment and rely on a router to communicate with Internet, DVR may have no way to get router’s external IP address. Since DVR needs to know the correct external IP address to determine when it needs to send DDNS update packet, it may not be able to send DDNS update packet at correct time if DVR does not notice the change of router’s external IP address. This could generate inconsistency issue between IP address and the domain name that user retrieved from DDNS provider. If DVR could detect the change of router's external IP, and send DDNS update packet to DDNS server at correct timing, then this self-adaptive function can keep consistency between domain name and external IP address. In addition to discussing the problem with DDNS update mechanism with DVR, the thesis also provides two possible methods to solve this issue, and compares the advantage/disadvantage with both ways. DVR related products are also introduced in this thesis, with brief discussion for compress technology and network protocols that DVR related products will use. Some of the real cases when developing DVR products with network protocols are also mentioned and described.