1. Common sense of network security for primary school students

1. Working in front of the computer for a long time: bad for the skin, bad for vision, and also affects memory

2. Internet access There are a few points you need to pay attention to when checking information: It is best to check a piece of content several times to determine which one is truly valuable to you

3. When making friends online, you need to be particularly careful not to tell strangers too much about your family and your family. Relevant real information

4 Common sense about surfing safety: Don’t take too long, have a certain self-view, don’t trust everything

5 Online safety: Remember to turn on anti-virus software and try not to download some .EXE files, don’t click on random pop-up ads

6 Password security common sense: Don’t tell strangers, you must remember it yourself, it is best not to use birthdays

2. Network security Tips

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Original publisher: blbrother

LOGO Computer Network Security Introduction to computer network security? With the rapid development of the Internet and the advent of network socialization, the network has ubiquitously affected all aspects of society's politics, economy, culture, military, ideology, and social life. At the same time, the number of intrusions and attempted intrusions against important information resources and network infrastructure continues to increase globally. Cyberattacks and intrusions pose a great threat to national security, economy, and social life. Therefore, network security has become the focus of common concern in all countries around the world today. Main contents Computer network security issues - Definition - Importance Knowledge related to network security awareness - What are the security risks that exist on the network - How to prevent risks and reduce threats - Common security techniques and precautions Network security related knowledge Network Security definition – The definition of security in the dictionary is measures taken to prevent espionage or deliberate sabotage, crime, and attacks. The general meaning of security is limited to the scope of computer networks. Network security is to prevent accidents in computer network hardware, software, and data. Or the sum of measures taken to deliberately destroy, tamper with, eavesdrop, counterfeit, leak, illegally access, and protect the continued and effective operation of the network system. –Account information and passwords –Research results, project documents, etc. –Private information (ID card number, phone number, license plate number) –Virtual property (game account, QQ account) –Real money (online bank account, stock fund account) Network security related knowledge What security threats does the network face? What are the main threats? –––––Viruses, Trojans (primary threats) Information leakage (intentional or unintentional) Social engineering and fraud Artificial specific attacks (APT) Security threats to wireless and mobile terminals Which operations may cause us to feel sick

3. Network security knowledge

Original publisher: Zhang Shengmao

Network security knowledge

1. The importance of network security

Network Information security is an important issue related to national security and democracy, social stability, and the inheritance and development of national culture. Its importance is becoming more and more important with the acceleration of global informatization. It mainly means that the hardware, software of the network system and the data in the system are protected from damage, alteration, and leakage due to accidental or malicious reasons. The system operates continuously, reliably and normally, and the network service is not interrupted.

2. Personal privacy security

Try not to provide detailed personal information online. Just make up some information or leave unnecessary fields blank. This is also something you need to pay attention to when registering for other online spaces. Please also pay attention to the information that is required to be filled in and may reveal your personal information.

If you receive a PM from a stranger for no reason, be careful! No matter what excuse the other party gives, do not disclose information related to yourself!

3. Online banking security

Personal bank account number should not be easily known to others except your parents unless necessary;

Personal bank password The setting should not be too simple or too complicated. If others don't know, it will be easier for you to remember.

4. Be careful when checking information online

Do not work in front of the computer screen for more than 1 hour at a time.

Don’t keep your eyes too close to the screen and sit in a straight posture.

Don’t make the screen settings too bright or too dark.

Go outdoors to breathe fresh air as appropriate.

Don’t shop online haphazardly.

Please learn how to protect yourself:

There are many anonymous dating sites online, so never go to an appointment alone. Use safe payment methods

4. What are some common sense about surfing the Internet?

Use an LCD screen and adjust the color to be comfortable for your eyes. The most important thing is that the brightness and color should not be too bright!

Chrysanthemum tea is a good drink to protect your "eyes"! Chrysanthemum tea can eliminate eye swelling and fatigue. If you drink too much water before going to bed, your eyes will be swollen like a panda when you wake up the next morning. There is a folk method to effectively relieve it, which is to use cotton dipped in chrysanthemum tea juice and apply it on the eyes. Around the eyes, this puffiness will be eliminated quickly. Chrysanthemum has a very good effect on treating eye fatigue and blurred vision. China has known since ancient times that chrysanthemum can protect the health of the eyes. In addition to smearing the eyes to eliminate puffiness, you can usually make a cup of chrysanthemum tea to drink, which can reduce the symptoms of eye fatigue. Elimination, if you drink three to four cups of chrysanthemum tea every day, it will also help restore vision.

There are many types of chrysanthemums. People who don’t know the art will choose chrysanthemums with white and large flowers. In fact, chrysanthemums that are small, ugly, and yellow in color are the best choice. Chrysanthemum tea actually does not add tea leaves, just soak or boil the dried chrysanthemums and drink it. It is a good drink for hot drinks in winter and iced drinks in summer. Chrysanthemum berry tea is a good eye-protecting drink!

Chrysanthemum tea is added with wolfberry, both of which are used in traditional Chinese medicine to protect eyes. The brewed tea is the famous "chrysanthemum and wolfberry tea". Especially students often have eye problems after reviewing their homework at night. People with fatigue and myopia often feel dry eyes. Regular drinking of chrysanthemum tea can improve eye discomfort.

There is also a kind of cassia seed that looks like black rice grains. It can be boiled into tea juice and drunk. It is also a good eye-protecting drink.

Computer people should use more. If you often need to use computers at work, or if you often play with computers, please be careful. Do you work on a computer for at least six hours a day? Remember to drink at least one bowl of miso soup every day! Miso is made from fermented soybeans and rice. It is rich in B12 and is an important source of B12 for vegetarians. Miso also contains a special enzyme that can expel radiation from the body. People who have undergone chemotherapy or use computers for a long time should consume it regularly. In order not to destroy the enzymes of miso, it is best to add it before turning off the heat when cooking. It can replace salt and soy sauce. Mix one tablespoon each of miso, lemon juice, and molasses and it becomes a delicious natural seasoning. It is most suitable for dipping blanched vegetables such as okra, kale, wild rice shoots, or broccoli.

Put a cup of hot water next to the computer

Do your friends also suffer from dry eyeballs and blurred vision? This is a common problem among many “computer people”! Internet fans who like to stay up late and surf the Internet are even more harmful to their eyes. Doctors suggest that for those who frequently use computers, it is best to check the screen so that the eyes are 10 to 20 centimeters lower than eye level, which can reduce the chance of eyelid lifting. In addition to giving your eyes more rest, you should also blink frequently to moisten your eyes, because most computer work For example, when focusing on the screen, the number of blinks will be reduced from 22 times per minute to 7 times, which will unknowingly cause excessive evaporation of tears on the surface of the eyeball, thus making dry eye syndrome worse. Place a cup of hot water next to the computer to increase the surrounding humidity to reduce eye discomfort.

The more care you take, the more health you will have!

The nemesis of computer radiation—cactus

In addition to attacking bad guys, cactus also has another benefit! I heard that placing a cactus in front of the computer desk can help reduce radiation; because cactus grows in places with strong sunlight, it has a particularly good ability to absorb radiation. Those students who sit for a long time and use computers should quickly find a cactus to protect their eyes. . As for how big you want, it depends on your needs!

The brighter the computer light, the more it hurts the eyes. The brighter the computer environment, the better.

Doctors point out that when using a computer, the surrounding environment should not be too bright, and do not use the computer near a window. Otherwise, glare and reflection problems may occur, causing eye fatigue and soreness. "Computer vision syndrome" and wrist and back injuries caused by long-term computer use have risen to the top of the list of occupational diseases in the United States, so we must pay attention to them. Taipei Municipal Zhongxiao Hospital ophthalmologist You Zhihao suggests that the brightness of the surrounding environment should not exceed three times the brightness of the screen. You can use a light meter to measure office and home environments. It is better if you can choose a light source that shines directly above your head.

Generally speaking, when using a computer, it is best to increase the "contrast" and "lower the brightness" of the screen to make it less likely to damage your eyes. When choosing a computer screen, it is best to use a flat, high-resolution screen (concave screens are better) and wear goggles; people who wear glasses are best to wear lenses with "anti-reflective coating". Prevent light reflection. People who work with computers for a long time may wish to wear a special pair of computer glasses. If you use a desktop computer, reduce the reading by about 150 degrees, and if you use a laptop computer, reduce the reading by about 200 degrees. This can avoid long-term near vision. objects, leading to increased myopia. Presbyopic users must wear multifocal glasses and increase the range of mid-range viewing to see more clearly.

5. What are some common sense about Internet safety?

With the continuous improvement of modern life, computers have begun to become popular in families, and people have begun to learn to arrange their lives and play games through the Internet. While enjoying games, making friends, shopping and even building a virtual family, people should not ignore that this virtual world also has potential dangerous factors. Especially for primary and secondary school students, they should master some common sense about online safety.

1. Do not meet strangers without your parents' permission.

If you must meet, it is best to go with your parents and choose some public places as the agreed location. 2.

Primary and middle school students are not allowed to tell others important information such as their photos, credit card or bank information without telling their parents or guardians. 3.

If you receive a vulgar or dirty email, do not reply. When you find some offensive pictures and texts on the Internet, you should immediately shut them down and tell your parents.

4. If someone’s words or words make you feel uncomfortable or worried, stop talking and tell your parents or guardians and ask for their help.

5. Do not give your home address, phone number, or school name to anyone without your parents' permission.

6. Don’t go to websites with harmful information out of curiosity.

6. What are the basic Internet knowledge for primary and secondary school students

1. Do not disclose your or your parents’ real information, such as name, address, school, phone number and Share photos, etc. and tell others online.

2. If you see uncivilized messages or pictures, you should inform your parents immediately.

3. Do not spread or repost other people’s content that violates the code of conduct for primary and secondary school students or even violates the law. Be a law-abiding citizen both online and offline.

4. Try not to publish your E-MAIL address in online forums and online bulletin boards. If there are multiple E-MAIL mailboxes, set different passwords as much as possible.

5. If you receive spam (emails from unknown sources), you should delete them immediately. Including emails with subjects such as greetings and award distribution.

If you have any questions, ask your parents or teachers immediately how to deal with it.

6. Do not browse websites or website sections that are “not suitable for children”. Even if you enter accidentally, you should leave immediately.

7. If you encounter someone hurting yourself online, you should tell your parents or teacher in time.

8. Appropriately control the time spent surfing the Internet, generally no more than 1 hour a day.

Pay attention to safety when surfing the Internet. If no precautions are taken, the harm of the Internet is not small. The following aspects should attract sufficient attention of students.

1. Beware of excessive use of online entertainment.

2. Beware of being deceived when making friends online.

3. Be selective about online content and take the initiative to stay away from websites that publish bad information.

4. Beware of "drugs" when staying online. That is to say, we must guard against virus intrusion and hacker attacks, and do not download programs and attachments from unknown websites.

7. Broadband knowledge

Broadband

In fact, there is no strict definition. Generally, the current upper limit of dial-up Internet speed is 56Kbps as the dividing line. 56Kbps Access methods above and below are called "narrowband", while access methods above are classified as "broadband". There is currently no generally accepted definition of broadband. From a general perspective, it is the bandwidth required to transmit various media that people can perceive on the network. Therefore, it is also a dynamic and developing concept. For home users, current broadband means that the transmission rate exceeds 1M, which can meet the needs of large amounts of information transmission such as voice and images.

Including: fiber optic, xDSL (ADSl, HDSL), ISDN (strictly speaking not broadband)

ADSL:

ADSL is English Asymmetrical Digital Subscriber Loop (Asymmetric Digital Subscriber Loop), ADSL technology is a new high-speed broadband technology that runs on the original ordinary telephone lines. It uses an existing pair of telephone copper wires to provide users with asymmetric uplink and downlink transmission rate (bandwidth).

Asymmetry is mainly reflected in the asymmetry of uplink rate (up to 640Kbps) and downlink rate (up to 8Mdps). The uplink (from the user to the network) is low-speed transmission, up to 640Kbps; the downlink (from the network to the user) is high-speed transmission, up to 8Mbps. It was originally developed mainly for video on demand services. With the development of technology, it has gradually become a more convenient broadband access technology and has been valued by the telecommunications department. Through the set-top box of Internet TV, many network applications that were previously impossible at low speeds can be realized.

DSL:

DSL (Digital Subscriber Line) technology is a broadband access technology based on ordinary telephone lines. It transmits data and voice signals respectively on the same copper line. , the data signal does not pass through the telephone switch equipment, which reduces the load of the telephone switch; and does not require dialing, is always online, and is a dedicated line Internet access method. DSL includes ADSL, RADSL, HDSL and VDSL, etc.

VDSL:

VDSL (Very-high-bit-rate Digital Subscriber loop) is a high-speed digital subscriber loop. Simply put, VDSL is a fast version of ADSL. Using VDSL, the maximum download rate within short distances can reach 55Mbps, and the upload rate can reach 19.2Mbps, or even higher.

Optical fiber access network:

Optical fiber access network (OAN) is an access network that uses optical fiber transmission technology, that is, all or part of the optical fiber transmission between the local exchange office and users communication system. Optical fiber has the advantages of broadband, strong long-distance transmission capability, good confidentiality, and strong anti-interference ability. It is the main implementation technology of future access networks.

The FTTH method refers to the direct access of optical fiber to users' homes. Generally, it only requires one or two user lines. It is not economical in the short term, but it is the long-term development direction and the ultimate access network solution.

FTTX LAN access method:

This is a broadband access solution that uses optical fiber plus Category 5 network cables to achieve Gigabit optical fiber to the community (building) center switch. The central switch and the corridor switch are connected with 100M optical fiber or Category 5 network cable. Comprehensive wiring is used in the corridor. The user Internet speed can reach 10Mbps. The network has strong scalability and small investment scale. There are also fiber-to-the-office, fiber-to-the-home, fiber-to-the-desktop and other access methods to meet the needs of different users. FTTX LAN mode adopts star network topology, and users enjoy the maximum bandwidth.

ISDN:

ISDN Integrated Services Digital Network is a digital telephone network that combines digital transmission and digital switching. The English abbreviation is ISDN. It can realize the user-end digital signal entering the network and provide end-to-end digital connection, so that the same network can be used to carry various voice and non-voice services. The ISDN basic rate interface includes two 64Kb B channels and one 16Kb D channel that can work independently. Select ISDN 2B D port and one B channel to access the Internet. The speed can reach 64Kb/s, which is 2.2 times faster than the general telephone dialing method (if Modem The transmission rate is 28.8Kb/s). If two B channels are used together through software, the communication rate can reach 128Kb/s.

Bandwidth represents a comprehensive indicator of the display's display capabilities, referring to the number of pixels scanned per second, that is, the sum of the number of frequency points displayed on all scanning lines per unit time, in MHz. The larger the bandwidth, the stronger the display control capability and the better the display effect.

The detailed calculation formula of bandwidth is as follows: Theoretically bandwidth B=r(x) *r(y) *V

r(x) represents the image on each horizontal scan line Number of pixels

r(y) represents the number of horizontal scanning lines per frame

V represents the screen refresh rate (i.e. field frequency) per second

B Indicates bandwidth

8. Do you have any knowledge about network security?

Provide some security knowledge, but it is a bit verbose~~ 1. Do not easily run programs that do not know the truth. If you When you receive an email with an attachment, and the attachment is a file with an EXE extension, you must not run it rashly, because this unknown program may be a system-destroying program.

Attackers often change the name of the system-destroying program and send it to you by email, with some deceptive subjects, tricking you into saying: "This is a good thing, you must try it." , "Help me test the program" and the like. You must be alert! What we should do when dealing with these seemingly friendly and well-intentioned email attachments is to immediately delete these files from unknown sources.

2. Block cookie information Cookies are cookies, which are data files sent to the computer by the Web server. They record information such as user names, passwords, and user interests. In fact, it makes it easier for you to visit the same site, for example, without having to re-enter your password.

However, the personal information collected by Cookies may be used by some people who like to play "pranks", which may cause security risks. Therefore, we can make some necessary settings in the browser and require the browser to Warn you before accepting cookies, or reject them altogether. Generally speaking, cookies will be automatically deleted from the computer when the browser is closed. However, many cookies will be uncharacteristically stored on the hard drive to collect user-related information. In fact, these cookies are designed to reside on our computers. on the computer.

As time goes by, there may be more and more cookie information, and of course our mood will become less and less secure.

In order to ensure foolproofness, these existing cookie information should be cleared from the hard drive immediately, and the cookie settings should be adjusted in the browser so that the browser refuses to accept cookie information.

The steps to block cookies are: first click the "Tools" menu item in the menu bar and select "Inter Options" from the drop-down menu; then select "Security" in the option setting box tab, and click the "Custom Level" button in the tab; at the same time, find the settings for Cookies in the "Security Settings" dialog box that opens, and then select "Disable" or "Prompt." 3. Regularly clear cache, history and the contents of temporary folders. When we browse information online, the browser will save the information we browsed during the process of surfing the Internet in the relevant settings of the browser, so that we can access the same information next time. We can reach our destination quickly, thereby improving our browsing efficiency.

However, the browser’s cache, history and the contents of temporary folders retain too many records of our surfing the Internet. Once these records are obtained by boring people, they may gain access to them from these records. Find clues about personal information. In order to ensure the absolute security of personal information, we should regularly clear the contents of cache, history and temporary folders.

Clearing the browser cache is not troublesome. The specific operation method is as follows: first click the "Tools" menu item in the menu bar with the mouse, and select "Inter Options" from the drop-down menu; then click on the options Select the "General" tab in the settings box and click the "Delete Files" button in the tab to delete the contents of the temporary folder in the browser; then click the "Clear History" button in the same dialog box to Delete content from your browser history and cache. 4. Install a firewall in your own computer to provide isolation protection for your own LAN or site. It is a safe and effective method commonly used at present. This method is not only for Web services, but also effective for other services.

A firewall is a functional module in a computer or network device located between the internal network and the Internet. It is an organic combination of hardware and software established in accordance with certain security policies. Its purpose is to provide internal The network or host provides security, controlling who can access internal protected objects from the outside, who can access the Internet from the internal network, and how to access each other. Therefore, in order to protect our computer system information from damage and threats from external information, we can install firewall software in our computer system.

5. Check the system information in time when you encounter an inexplicable failure. When you are surfing the Internet and suddenly feel that something is wrong with the computer, it seems like someone is remotely controlling you. At this time, you must stop what you are doing in time and immediately press the Ctrl Alt Del compound key to check whether the system is running any other programs. Once you find that an inexplicable program is running, stop it immediately to avoid any damage to the entire computer system. A bigger threat.

However, not all programs appear in the program list when running. Some programs such as Back Orifice (a hacker backdoor program) do not appear in the process list of the Ctrl Alt Del composite key, so if Your computer is running the WIN98 or WIN2000 operating system. It is best to run "Accessories"/"System Tools"/"System Information", then double-click "Software Environment", select "Running Tasks" and find yourself in the task list For programs that you are not familiar with or that you are not running, you should terminate it immediately as soon as you find the program to prevent future troubles. 8. Encryption protection of confidential information Encrypting storage and transmission of confidential information is a traditional and effective method. This method is particularly effective in protecting the security of confidential information and can prevent wiretapping and hacker intrusion. In the current Web service-based Some network security protocols have been widely used.

O（∩_∩）O haha~, I have said so much, I wonder if you have bothered to read it. In fact, as an ordinary Internet enthusiast, you don’t need to think about it. Those unsafe factors are necessary to pay attention to, right? .

9. What are some tips for surfing the Internet?

Tips for speed dialing to surf the Internet. At present, the vast majority of Chinese netizens access the Internet through telephone dialing, so during the dialing process, we It is inevitable to encounter problems of one kind or another, such as frequent disconnections when dialing, no sound from the modem when dialing, or long waiting times during dialing, etc.

In order to solve the above problems, many "heroes" can be said to have used their brains. The acceleration secrets they have obtained through "practice" have indeed brought spiritual and material benefits to the beginners. above results. Also here, in order to help us beginners improve the speed of logging in to the Internet, the author has also listed down some tips about dial-up networks that I have read or used in practice, which can be regarded as a small contribution to junior dial-up users.

1. Delete unused protocols. If you use a single computer to access the Internet, you generally only need one TCP/IP protocol. Therefore, we can completely delete all protocols except the TCP/IP protocol, which will not only increase the speed of machine startup but also increase the success rate of dial-up.

The specific operation method is to open the dial-up network parameter setting dialog box, then select the protocol except TCP/IP protocol and click "Delete". But don't delete the dial-up network adapter by mistake.

2. Delete useless virtual private network VPN. System virtual private network adapter VPN is generally designed for accessing corporate networks. It has basically no practical value for ordinary users, and it also affects the login speed. one so we can remove it without hesitation. The steps are: In the dial-up network parameter setting window, select the "Configuration" tab, and select "Dial-up Network Adapter #2 (VPN)" and "TCP/IP→Dial-up Network Adapter #2 (VPN)", and then click Click the "Delete" button to delete the specified virtual private network device.

3. Change the "Main Network Login" option "Microsoft Friendly Login" is the default setting of the system, but it also delays the login time. The method to change the above default settings is to select "Microsoft Network User" in the "Main Network Login" drop-down list box in the "Network" dialog window, and then click "OK".

If this option is not available in the "Main Network Login", you can add the option by adding a customer. 4. Set redialing when the phone is busy. It is common to encounter a busy line when dialing, and busy dialing also costs users time.

For this we should make a choice about dialing busy. First double-click the "My Computer" icon, select "Dial-up Networking" in the window that opens, then select the "Connect" option (if you cannot find it, please maximize the "Dial-up Networking" folder window), and then select " Settings tab, then make your selection from the options in the Redial area.

5. Turn off debugging mode. In the "Connection" tab of the "Modem" settings dialog box, click the "Advanced" button and type "C0" in the "Additional Settings" text box to turn off Modem. debugging mode to increase its speed. However, this option requires that the original manufacturer's Modem driver must be used, otherwise the modified value will be invalid.

6. Let the dial-up window connect automatically. Every time you dial-up to access the Internet, the system will pop up a dial-up window to prompt the user to enter an appropriate password, thus affecting the login time. If the user is surfing the Internet at home or in a place they think is safe, they can check the "Save password" or "Automatically connect" dialog box in the "Connect to" window, so that the user does not have to re-enter their password every time they log in. and wait for the confirmation process, thus increasing login speed.

7. Set reasonable parameter values ??for the system port. Setting the port value too small will cause slow communication and thus reduce the Internet speed. Therefore, it is necessary for us to set reasonable parameter values ??for the system port. It must be turned on during setting. System Properties dialog box and locate the Ports settings dialog box. Then follow the steps below to check each port.

Enter "Port Settings" and change the value of "Baud Rate" to 57600 or 115200. Most modems are set on port 1 or 2.

Change this setting to the maximum value. At the same time, in the port settings dialog box, please set Data Bits to 8, Parity to None, Stop Bits to 1, and Flow Control. Set to "Hardware".

Then click the "Advanced" button and set all the values ??inside to the maximum. If something goes wrong, try lowering it a bit or selecting "Restore to Default".

In addition, if the Modem uses port 3 or 4, you need to open the system configuration file Win.ini for settings. The method is: use "Notepad" to open Win.ini under the Windows folder, find the [Ports] section, and change 3: (or 4:) = 9600, n, 8, 1, x to 115200, n, 8, 1,p.

Among them, when the last parameter is "x", it represents software flow control (Software Flow Control), when it is "p", it represents the use of hardware flow control (RTS/CTS), and when it is "" (blank) When it represents no flow control. 8. Turn off the security check setting item. Before dial-up connection, the system default is to check whether anyone else on the Internet has accessed your shared folder. This also requires a certain amount of time.

In order to save this time, we can turn off this option by bringing up the "Inter" dialog window from the "Control Panel" and uncheck "Perform system security check before dialing" under the "Connection" tab " hook number. 9. Adjust the line status. If the phone line quality is poor and disconnected frequently, it will also seriously affect the speed of dial-up Internet access.

The specific solution is: click "Start → Settings → Control Panel → Modem", select "Properties/Connection Page/Advanced Options" from the Modem, and fill in "S10=50" in the additional settings ” and “S25=200”, the former can force the Modem to remain connected for 5 seconds when the carrier is temporarily lost, while the latter can force the Modem to remain connected for 2 seconds when the DTR (Data Terminal Ready) signal is momentarily invalid. connection status, thus avoiding Modem disconnection failure when the line transmission quality is poor. 10. Reduce Internet connection time through options By default, Windows 98 requires activating a large number of options that are useless for dial-up users.

"Log on to the network" in the default settings.