Programmer Think

1. Preface I finally don't need to debug a hardware device and install an APP. If I download someone else's network debugging assistant in the APP store and have advertisements, I might as well write a relatively complete network debugging assistant directly. At present, the supported functions include tcp client and server, udp, low-power Blu ...

1. Agreement: an agreement. 2. Protocol layering: (1) OSI (open system interconnection) seven layer model (2) TCP/IP five layer model (3) TCP/IP four layer model Layer namefunctionRelated agreementsapplication layerResponsible for communication between applications HTTP SSH DNS Display layerConvert the network datagram into the package req ...

Communication between C# upper computer and Schneider PLC Introduction to ModbusTCP communication protocol Schneider PLC communication is a Modbus protocol based on Ethernet TCP/IP, in which TCP is what we call ModbusTCP protocol. Modbus protocol is an application layer message transmission protocol, including ASCII, RTU, TCP and other messag ...

Involving knowledge 1. The essence of handshake and wave In fact, I think waving and shaking hands are completely confusing concepts. The change of serial number and verification number completely depends on whether you are the data sender or receiver. The data here only refers to the data carried in the application layer http, excludin ...

1. The network is divided by coverage: LAN / man / WAN, Internet / Internet, Ethernet / token ring - networking mode 2. Each host must be represented by one in the network to realize point-to-point accurate communication IP address: ipv4: uint32_t unsigned 4-byte integer} DHCP/NAT} ipv6: uint_t addr[16]; Each data in network communication mu ...

Communication between different hosts: ❤️ The concept of process communication originated from single machine system. Since each process runs within its own address range, the operating system provides corresponding facilities for process communication to ensure that two processes communicating with each other do not interfere with each o ...

TCP server (server) If you want to perform the functions of the tcp server, you need to perform the following process Socket create a socketThe bind method binds IP and portlisten makes the socket passiveaccept waits for unprovoked links (you must create a new listening socket and redefine a new receiver)recv/send receive send data For accep ...

preface In the process of TCP/IP related development, it is often necessary to check the problems such as packet loss, wrong packet and blocked flow. Because the TCP/IP forwarding surface involves software and hardware, and there are many functions and branches in the software process, it is difficult to add printing or analyze the process.Thi ...