linux packet sniffer

Test kernel version: Linux kernel 2.6.35 ---- Linux kernel 3.2.1 Original works, reprint please mark http://blog.csdn.net/yming0221/article/details/7572382 For more information, see column http://blog.csdn.net/column/details/linux-kernel-net.html Author: Yan Ming Knowledge Base: this firewall is developed based on a good concept of the

Tcpdump helps us capture and save network packages. the saved network packages can be used to analyze network load conditions. The packages can be parsed using the tcpdump command, or saved as files suffixed with pcap, use wireshark and other software for viewing. The following nine examples of using tcpdump are provided to illustrate the specific use of tcpdump. 1. packet capture for specific network ports TcpdumpThis helps us capture and save networ

Socket programming practices in Linux (4) TCP packet sticking problems and common solutions Generation of TCP packet sticking problems Because the TCP protocol is a byte stream-based and borderless transmission protocol, it is very likely to cause a packet sticking problem. In addition, the adhesive

1 Introduction to Analog delay transferNetem and Tc:netem are a network emulation function module provided by Linux 2.6 and above kernel versions. The function module can be used to simulate complex Internet transmission performance in a well-performing LAN, such as low bandwidth, transmission delay, packet loss and so on. Many distributions of Linux with

Use Linux to implement router and packet filtering firewall-Linux Enterprise Application-Linux server application information. The following is a detailed description. Routers and firewalls Vro is a widely used device between IP segments. There are many ready-made products on the market. In applications, we often con

Original article link Tcpdump is a tool used to intercept network groups and output group content. It is simply a packet capture tool. Tcpdump is the preferred tool for Network Analysis and troubleshooting in Linux based on its powerful functions and flexible interception policies. Tcpdump providesSource codeOpen interfaces, which are highly scalable and useful for network maintenance and intruders. Tcp

Function description: dumping network transmission data. Syntax: tcpdump [-adeflnNOpqStvx] [-c packet count] [-dd] [-ddd] [-F expression file] [-I network interface] [-r packet file] [-s data packet size] [-tt] [-T data packet type] [-vv] [-w data packet file] [output data c

Simulate the network packet sending and receiving delay for the specified IP port on Linux. When compiling network applications, we usually test and debug the network on a LAN or even a local machine. Is there a way to simulate a complex Internet environment-especially network latency-for applications without modifying their own code in an Intranet environment with good network conditions? This was my idea

The packet capture tool tcpdump in linux. The packet capture tool has two advantages: one is snort and the other is tcpdump. this time, we don't mention snort. Although the tool is powerful, it is complicated, and tcpdump is relatively simple. Tcpdumpwindows and tcpdump This article describes the packet capture tool

Https://www.tuicool.com/articles/7ni2yyr Recently work encountered a server application UDP lost packet, in the process of checking a lot of information, summed up this article for more people's reference. Before we begin, we'll use a diagram to explain the process of receiving a network message from a Linux system. First of all, network packets sent through the physical network to the NIC driver will read

Linux Network Application Programming Hub (Packet Tracer simulation), packettracerIntroduction to Packet Tracer 1: Overview of hubs Connect to the received signal for regenerative shaping and amplification, to expand the transmission distance of the network, while all nodes are centered on it. Working at the bottom layer (Physical Layer) of OSI (Open System Inter

This is a BDP test in rhca, which is also a very common simulation of latency and packet loss. I will share it with you now. We also use the application software to test TCP/UDP comparison. When we test the impact of BDP on TCP/IP, we all need some network latency and packet loss simulation, many commercial software can do this. In fact, the perfect Linux itself

is completed. Four, knowledge expansion in the above simulation mode debugging, we can understand the ICMP packet from one device to another through single-step debugging, if we want to understand how the packet has changed in this process, we need to do the following: Through this graph we can see that the packet of the ping command is the Ethernet hea

What is Cisco Packet tracer?The Cisco Packet Tracer is a powerful network simulation tool for training in Cisco certifications. It gives us a good view of the interfaces of each router and network device, with many options, and we can use unlimited devices in the network just like with physical machines. We can create multiple networks in a single project for specialized training.

A large number of avahi-daemon[3733 were found when checking the log files of Linux]: Invalid query packet error (different number of servers corresponds) 3 07:00:01 hostname auditd[3143]: Audit Daemon Rotating log files 3 08:02:39 hostname avahi-daemon[3733]: Invalid query packet. 3 08:03:19 hostname Last message repeated 7 times 3 08:29:24 hostname avahi-dae

The packet capture tool has two advantages: one is snort and the other is tcpdump. this time, we don't mention snort. Although the tool is powerful, it is complicated, and tcpdump is relatively simple. Tcpdumpwindows and linux versions. You can download the linux version from www.tcpdump.org. after tcpdump is installed, run tcpdump: Two of the best

Linux Network Application Programming Packet Tracer installation and interface introduction, packettracerIntroduction to Packet Tracer 1 Packet tracer is an auxiliary learning tool released by Cisco. It provides a network simulation environment for beginners of Cisco network courses to design, configure, and troublesh

In fact, it has been a long time to explore the problem of network card packet capture. I found some basic things in the last few days. I will just repeat them here. Packet Capture first needs to know that the data transmitted through the NIC is actually through the underlying link layer (MAC). in Linux, the data traffic we obtain from the NIC is actually directl

Packet Tracer Introductory One, Packet tracer introductionPacket Tracer is an assistive learning tool released by Cisco, which provides a network simulation environment for beginners in learning Cisco Web courses to design, configure, and troubleshoot network failures. The user can set up the network topology directly using the towing method in the software's graphical user interface, and can provide the de

generally also has the distributed detector, these detectors are placed in each kind of application server and other network nodes, not only can detect from the network external attack, simultaneously to from the internal malicious destruction also has the extremely strong guard function. The monitoring firewall has gone beyond packet filter and proxy Server firewall in security, but its implementation cost is high. Based on the comprehensive conside