Zkteco PL-52A12G — пользовательское руководство по терминалу с TFT экраном 2.4 дюйма [34/55]

26 2.4 Inch TFT POE Terminal User Manual

QoS: Quality of Service, a kind of network secure mechanism, a technology of solving network delay and

congestion.

Fig 2.31

IGMP: It is a multi-cast protocol of internet family, helping IP Host report their membership to the

adjacent routers.

Fig 2.32

Fig 2.33

DDNS: The user’s dynamic IP address is mapped to a fixed domain name resolution service.

When connecting network each time, the client’s procedure would pass the host’s IP address to the

server’s procedure which provides DNS service and realize domain name resolution. That is, DDNS

captures the changing IP address and corresponds the domain name, which is how other clients

communicate.