computer forensics basics

. com domain receives the request, it will find a management. com domain's next-level DNS server address (baidu.com) to the local DNS server if it cannot implement the resolution itself. When the local DNS server receives this address, it will find the baidu.com domain server, repeat the above 3,2,1 action to query until the www.baidu.com host is found.(5), the data is embedded in the TCP packet returned.4. TCP protocolThe TCP protocol embeds the port of the HTTP protocol in the packet and sends

; 2 in the second "show" in the bar, drag the slider to 15 minutes, that is, 15 minutes without action, the monitor off, If the impact of watching movies, can be dragged to the far right "never"; 3 and then click on the "General" label, look at the other settings, generally do not modify what, if you want to modify, remember what was originally; 4) Point "Off" button, the power and screensaver completed the settings; Ubuntu

Computer hardware can actually be more easily divided into CPU + memory +io devices. The three of them are through a bus to exchange data, and you know in the three CPU speed of the fastest, memory second, IO device third, to make the three coordination of communication requires a certain control. 2. our CPU has its own local bus, the same memory, the local bus through the motherboard of the South Bridge chip link together to communicate. North Brid

rint:]: Printable characters[: Cntrl:]: Control (nonprinting) character[: Graph:]: Graphic character[: Xdigit:]: hexadecimal characterInode,block,bitmapIndex node? The Inode (index node) table contains a list of all file system files? A node (an index node) is a table item that contains information about the file (metadata), including:File type, permissions, Uid,gidNumber of links (pointing to the number of path names for this file name)The size of the file and the different timestampsData bloc

and there is content to be overwritten)Add content echo >> file name (> Overwrite action)8 Delete Directory rmdir/q/s folder nameDelete File del file nameOptional parameters-S recursion-Q (quite) quiet-F (Force) mandatory9.move MobileIpconfig view IP addressPing Test network connectivity For example: Ping www.baidu.com12. Configure the Hosts file to bypass DNS resolution and directly look for IP addresses.Hosts file address C:\Windows\System32\drivers\etc\hostsUsage: Add directly to hosts ' Hos

operation is complete before returning, ensuring the reliability of the dataFdatasync: Data block synchronization for individual files. Wait until the disk operation is complete before returning, ensuring the reliability of the dataMsync: Synchronizing dirty pages generated by mmapThe page recycling mechanism consists of three parts, data brush out flush, swap swap, releasing release.Data brush flush and data synchronization are similar, that is, the backup file of the page cache is synchronize

1. Introduction1 What is data compression?Data compression reduces the amount of data sent or stored by partially eliminating the inherent redundancy in the data.Data compression improves the efficiency of data transfer and storage, while protecting the integrity of the database.2 Data compression methodThe data compression method is divided into lossless compression and lossy compression.Lossless compression is suitable for text or programs. lossy compression is suitable for images, video, and

Before learning about networks, review the basics of computer networks. Lu Xun said that there is a huge copy of the article in the world. If you have any questions, you can copy the book based on your basic knowledge. A layered model 1. Why Layer In order to simplify the network design complexity, communication protocols adopt a layered structure, and Protocols at different layers are mutually indepe

the new.3 Enter the command to edit the password.5 single-user mode hack password1 start the virtual user, and at the time of the Grub boot interface, select the startup item with the up and down keys.2 use ' e ' to enter the startup item of your choice, then use the up and down keys to move the cursor to "linux16 ...". "That line, delete" rhgb quiet, then use the end key to move the cursor to the tail of the character, add the parameter init=/bin/sh, to tell Grub to start the operating system,

The philosophical thought of LinuxEverything is a file (including hardware)Small, single-use programsLink programs to accomplish complex tasks togetherAvoid confusing user interfacesConfiguration data is stored in textDevelopment interface StandardABI (Application Binary Interface)Describes the underlying interface between the application and the OS;API (Application Programming Interface)Define the interface between the source code and the libraryPOSIX (Portable Operating System Interface)A seri

languages (HTML, Perl, Python, etc.) 9. Database Technology The development of data management technology Data model relational database language SQL Database management System 10. Computer operation system The development of the operating system User interface Processor management (process concept, Process control, synchronization, communication, scheduling, multithreading) Memory management Fi

of the run to get results, often up to hours from the submission of a job to the result of the Operation . Imagine a scene: a June b June three programmers at the same time in the debugging program, once a June write a comma, it may take half a day to see the knot Because the result of B June is also calculated at the same time. Time must be long. Word: We're all working together. Data (tapes) Many programmers miss their first-generation computers and can debug their programs on the

3640 Vswitch: Cisco 3560, Cisco 3750, and Huawei 9306 Switches 2Network Security Device Firewall:Attackers can defend against attacks from the company's internal and external networks. Cisco ASA 5505, 5510, 5520, 5540, 5550, 5580 VPNDevice:Virtual Private channel through the Internet 3And wireless network devices:Wireless Router (TP-LINK), wireless network card, Wireless Bridge 4Network device manufacturer:CiscoCompanies, Huawei companies Vi. Network Topology 1) Star-based topology Advantages:

opted out.Gnu? GNU (GNU is not Unix)? 1984 was initiated and created by Richard StallmanThe goal is to write a large number of free software compatible with UNIX systems? Official website: http://www.gnu.org? GPL (GNU general public License)Freedom Software Foundation: Free Software FoundationAllow users to arbitrarily copy, transfer, modify and republishSoftware that is re-released based on free software modification is still subject to the GPL? LGPL (Lesser general public License)? LGPL is lo

*:????? ?name: Description of functionality??????????????? ? Synopsis: Syntax format??????????????? ? DESCRIPTION: Description??????????????? ? Options: Option??????????????? ? EXAMPLES: Using the example??????????????? ? AUTHOR: Author??????????????? ? BUGS: How to Report program bugs??????????????? ? See ALSO: Reference??????????????? ?...Vi. Basic directory names and functions of Linux distributions???? ? directory name function???? ?/bin Basic Command Program files available to all users;??

Write code also to read, love the whole stack, more love life. Daily update of original it programming techniques and daily practical videos.Our goal is: To play with the server Web development, to understand the mobile side, the computer client is a cinch.This tutorial is a basic tutorial for anyone who is interested in learning software development. Of course, because of the coherence of technology, it is recommended to view in order.Last class:

Socket programming: Computer Network basics, Before learning about networks, review the basics of computer networks. Lu Xun said that there is a huge copy of the article in the world. If you have any questions, you can copy the book based on your basic knowledge. A layered model 1. Why Layer In order to simplify the n

Socket programming: Computer Network Basics Before learning about networks, review the basics of computer networks. Lu Xun said that there is a huge copy of the article in the world. If you have any questions, you can copy the book based on your basic knowledge. A layered model 1. Why Layer In order to simplify

Linux first day: Computer Basics and CentOS system installationThe philosophical thought of LinuxEverything is a file (including hardware)Small, single-use programsLink programs to accomplish complex tasks togetherAvoid confusing user interfacesConfiguration data is stored in textDevelopment interface StandardABI (Application Binary Interface)Describes the underlying interface between the application and th

Network Learning notes-Computer Network basics 1 What is network: The network is the interface between several computer hosts or network printers, through the network cable or wireless network technology, connect these hosts or devices so that data can be transmitted through network media (network cable or wireless network technology. 2.