netflow packet

obtain the corresponding MAC address through the IP address, so you need to use the ARP protocol to convert IP address to MAC address, At the same time in order to be able to quickly find the destination of the MAC address, each node will have an ARP cache, for the preservation has been turned a good MAC address, you can use the Arp–a command under the console to view the ARP cache table. and ARP specific process is when you need to get a remote MAC address via IP, the system will first check

Ipv6 Protocol packet format 1. ipv6 basic format ipv6 packet format from the perspective of simplicity, it is simpler than ipv4, and the length of the ipv6 basic header is fixed. Compared with ipv4, ipv6 removes some headers and gets all of these headers to the end of the extended projection. The ipv6 packet format is as follows: version: 4 bits version number ip

Compile and install the NIC Driver in linux (NIC packet loss)-Linux Enterprise Application-Linux server application information. The following is a detailed description. Install and compile the NIC Driver In the past two days, I found that the packet loss of a server is very serious. The snmp package can be obtained when the cacti monitoring tool is used, which is often unavailable. The

This article mainly introduces the random red packet generation algorithm of php version, which has some reference value. interested friends can refer to the function of red packet sending recently, so I wrote a red envelope generation algorithm. Requirements for red packet generation algorithmsWhether to generate all red packets in advance or randomly generate

In the previous article, we introduced some basic content of the OSPF protocol. If you have any questions, please refer to the new guide to OSPF routing protocol. Next, we will discuss other issues related to the OSPF routing protocol. ◆ OSPF packets OSPF has five types of packets: HELLO Packet (Hello Packet) The most common type of message is periodically sent to the neighbor of the Router. The content inc

The backboard bandwidth is the maximum amount of data that can be transferred between the vswitch interface processor or interface card and the data bus. The higher the bandwidth of the backboard of A vswitch, the stronger the ability to process data, but the design cost will also rise. However, how can we check whether the bandwidth of A vswitch is sufficient? Obviously, the estimation method is useless. I think we should consider the following two aspects: 1) The sum of the total port capacity

wireshark Packet Analysis data Encapsulation Data encapsulation ( data encapsulation PDU osi seven-layer reference model, Each layer is primarily responsible for communicating with peers on other machines. The procedure is in the Protocol Data unit ( PDU ), where each layer of PDU wireshark packet analysis of the actual combat details Tsinghua University Press to help users understand the data

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. Tcpdump exists in the basic Linux system. Becaus

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 Linux kernel network stack. My analysis of the network stack is based on the earlier version (Linux 1.2.13 ), after clarifying the network stack architecture, we

1 Introduction to Analog delay transmission Netem and Tc:netem are a network emulation module provided by the Linux kernel version 2.6 and above. This 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 Linux that use the Linux 2.6 (or above) version of the kernel feature the kernel, such as Fedora, Ubuntu, Redh

Implement ARP spoofing data packet monitoring in JavaText/rexcj source/blogjava Transferred from:Http://www.pin5i.com/showtopic-18934.html If there is something unpleasant recently, it is the pain of sharing networks with people, especially when other sharing users use those P2P tools to download software, but you watch the Web progress bar crawling a little bit, that kind of pain is hard for people like me who are at the insect level. I can't bear it

vswitch, connect one by one, and check whether the connection is normal until the connection is interrupted. Then we can determine which network cable is faulty, find the problematic host through the network cable. . Virus detection and removal can generally solve the problem. However, we can see that this workload is very large. If there are enough switches and there are more than one faulty computer, it will take a long time for us to completely solve the network problem. However, we have a t

In FreeBSD use, sometimes you may need to know your host or network card packet (Packet) of the flow, to understand network traffic and network card load, to the system management personnel for reference. Here, I write my own server configuration in this way and experience, to share with you friends. I. Installation of MRTG drawing software Cd/usr/ports/net/mrtg Make install can be installed successfully

transparent to the user, and the user sees only one virtual server as lb, and the RS group that provides the service is not visible. When a user's request is sent to the virtual server, LB forwards the user request to Rs according to the set packet forwarding policy and the load balancing scheduling algorithm. RS then returns the user request result to the user.　　Two. LVS Kernel model 1. When the client's request reaches the load balanc

For the analysis of the implementation of TCP packet restructuring, refer to the detailed explanation of TCP/IP, discusses the implementation of TCP in detail, and roughly summarizes how TCP ensures the correctness and reliability of data packets to the application layer, that is, how TCP restructured data packets. First, we need to design two message queues, one for storing normal incoming packets and the other for storing out-of-order incoming packe

The IPV6 extended packet header is followed by the eight basic fields of the IPv6 packet header, which is the extended header and data part. The extension header is not fixed. If it exists, the extension header and data are followed by eight basic fields. The extended header part is not fixed. If it exists, it is attached in 64 bits. Multiple extended packet head

Http://www.cnblogs.com/ydhliphonedev/archive/2011/10/27/2226935.html IOS network packet capture method During iOS development, various network access problems often occur. In the past, packet capture tools were not used, and many network problems were solved. Now, we have finished. This article provides two methods for packet capture: 1. Network Sharing + visual

we will never be able to detect whether the attack is successful. The following is a concept validation code for ICMP ping injection. This is a wise choice, because hosts on the internal network will not block ICMP echo requests. # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include # Include "protocols. h"# Include "packets. h" This is a very bad test.We send A ping packet

Function 1:PCAP_NEXT_EX (pcap_t* p,struct pcap_pkthdr** Pkt_header,Const u_char* Pkt_data)Read a packet from a network interface or offline capture method (such as a read file). The function is used to regain the next available packet without using the traditional callback method provided by Libpcap. PCAP_NEXT_EX assigns a value to the Pkt_header and Pkt_data parameters with pointers to the head and the nex

+ SMAC source MAC address 48bit = 6 bytes + type domain 2 bytes) 14 bytes and the CRC check at the end of the frame is 4 bytes, so the rest of the places that carry the upper-layer protocol, that is, the maximum data domain can only have bytes, which we call MTU. The UDP packet size should be 1500-IP header (20)-udp header (8) = 1472 (bytes)The TCP packet size should be 1500-IP header (20)-TCP Header (20)