Internet Protocol - MQTT message queue telemetry transmission protocol

catalogue MQTT MQTT (Message Queuing Telemetry Transport) is a "lightweight" communication protocol based on Publish / Subscribe mode. The protocol is built on TCP/IP L4 Layer and released by IBM in 1999. It is a Publish / Subscribe message protocol designed for remote devices with low hardware performance and scenarios with poo ...

Posted by WRa on Sat, 05 Mar 2022 07:44:29 +0100

Summary of common functions of multi process and multi thread programming in linux

Multi process Create process When executing a program in multi process mode, you need to create a process before forking #include <unistd.h> //Create a process and return the number of the process in the program pid_t fork(void); //Return process number pid_t getpid(void); be careful: Child processes and parent processes shar ...

Posted by jpschwartz on Thu, 24 Feb 2022 09:08:40 +0100

Basic flow of C/S program based on TCP protocol

Server communication process Server: 1,adopt socket()Function to create a to receive a connection request socket 2,To construct the host connection address sockaddr_in structural morphology,include sin_family,sin_port,sin_addr Three members 3,binding sockaddr_in Structure and socket 4,adopt listen()Function will stocket Set to listenin ...

Posted by mdemetri2 on Wed, 23 Feb 2022 02:59:37 +0100

Design and implementation of computer network course design and network chat program

Experimental topic Design and implementation of network chat program Experimental purpose 1. Understand Socket The principle of communication, learn to use Socket for simple network programming, and write a chat program on this basis. 2. Understand Qt programming and be familiar with C + + language. overall design 1. Background knowledge So ...

Posted by intenz on Fri, 11 Feb 2022 09:24:44 +0100

Summary of the most complete knowledge points of computer three-level network technology [6]

Introduction before chapter This chapter focuses on the basic concept of switch, spanning tree protocol STP, content of switch table, switch configuration, switch mode, switch VLAN configuration, virtual LAN technology and switch STP configuration Test point 1: basic concept of switch 1. Basic concepts LAN switch is a network co ...

Posted by etingwall on Sun, 06 Feb 2022 22:16:46 +0100

2021-06-05 - Analysis of CSRF and XSS

Analysis of CSRF and XSS preface Bloggers recently had an interview and encountered a question: * * What are the principles of CSRF and XSS? How to prevent CSRF and XSS** Because the blogger didn't understand this part deeply enough, the answer in the interview was not comprehensive enough. Today, let's discuss the mystery behind CSRF and X ...

Posted by dazz_club on Sun, 30 Jan 2022 05:22:08 +0100

windows intranet information collection

introduction: After entering the intranet, it is a point-to-line and then face-to-face test. First, find out the current machine situation, such as the role in the domain and the services provided; Then use this as a springboard to collect information from other machines. When enough information is collected, the higher the possibility of winni ...

Posted by inutero on Wed, 19 Jan 2022 12:48:11 +0100

dried food! Summary of common methods of Intranet penetration

Gongzong No.: Black palm A blogger who focuses on sharing penetration testing, hot spots in the hacker circle and hacker tool technology area! preface During intranet penetration, a WebShell or CobaltStrike, Metasploit, etc. are just the beginning. It is more about moving horizontally within the intranet, expanding the results and reaching ...

Posted by Crashin on Sat, 15 Jan 2022 23:04:25 +0100

Computer network -- network layer

Self use ~ do not spray 4.1.1 overview of network layer functions *Overview of network layer functions The packet is transmitted from the source end to the destination end to provide communication services for different hosts in the packet switching network *Network layer functions 1.Routing and forwarding 2.Heterogeneous network int ...

Posted by Panthers on Sun, 09 Jan 2022 09:51:40 +0100

HCIA/HCIP uses eNSP to simulate BGP group attribute policy configuration instances

Simulate BGP group attribute policy configuration instance using eNSP Problem elicitation As shown in the figure There are two user network segments in AS 300 When users in AS 100 access these two network segments It is hoped to realize traffic sharing on R2 and R3 When AS 200 accesses these two network segments It is hoped that traf ...

Posted by gth759k on Mon, 03 Jan 2022 10:14:37 +0100