On Computer Security Question 10

Briefcase overview: If you frequently work with files outside of your primary computer, such as using a laptop, you can use Briefcase to synchronize the files with the corresponding section on your primary computer when you end file processing.

When you reconnect your laptop to your primary computer (or insert a removable disk that contains a modified file), Briefcase automatically updates the file on your primary computer to the modified version. You don't have to move the modified file out of the Briefcase, or delete the existing copy on the primary computer.

Briefcase stores the file and displays the status of the file. For example, it can show if a file is linked to the original file on the main computer, or if a file is orphaned. This information helps you organize your files and prevent accidental deletion or copying on the latest version of your files.

Note. When you use Briefcase to copy files from your primary computer to your laptop, you must connect the two computers over a network or direct cable connection.

Use Briefcase to sync files connected to your computer:

While the computer is connected, open Briefcase on your laptop and copy the files you want from the primary computer.

Work on files on a laptop.

When you're done working on the file, connect both computers (if they've been disconnected), open Briefcase on your laptop, and complete one of the following steps:

To update all files, on the Briefcase menu, click Update All.

To update only some of the files, select the files you want to update, and then on the Briefcase menu, click Update Selection.

Use Briefcase to synchronize files stored on removable disks:

Insert the removable disk into the disk drive of the primary computer.

Open Briefcase, and then copy the appropriate file to the briefcase.

Drag the Briefcase to disk.

The files in the Briefcase are copied to disk.

Remove the disk from the primary computer and insert it into the laptop's disk drive.

Open the Briefcase from disk and work with the files in it. When you're ready to sync your files, remove the disk from your laptop and plug it back into the disk drive on your primary computer.

Open the Briefcase from the disk, and then do one of the following steps:

To update all files, on the Briefcase menu, click Update All.

To update only some of the files, select the files you want to update, and then on the Briefcase menu, click Update Selection.

File synchronization only for the briefcase will not control your computer, unless other Trojans or malicious programs are used, which can be checked using some security tools. Kingsoft, Ruixing, 360, etc.

If you lose files, you can install data recovery software to recover them, but they cannot be 100% recovered.

You can see the system log for this.

Enabling logs in the server settings allows you to log in to your login information, including your IP address.

You can install some auxiliary software detection, and it is best to install a firewall!

In the last 3 episodes, we've talked about how computers are interconnected and allow us to communicate across the globe instantaneously, but not everyone who uses the Internet will behave in a way that doesn't harm others, just like in the real world, we use locks and fences to keep things physically safe, and we have the police to reduce crime.

Computer information systems are not secure, and their insecurity factors include the computer information system itself, natural, and man-made.

The factors that can lead to the insecurity of computer information systems include software systems, hardware systems, environmental factors and human factors.

1.Software System:

The software system generally includes system software, application software and database parts. Software is a program written in a programming language that can be processed by a machine, which can be tampered with or stolen, and once the software is modified or destroyed, it will damage the function of the system and even paralyze the entire system. The data inventory has a large amount of various data, and some data materials are invaluable, and if they are destroyed, the loss is difficult to estimate.

2.Hardware system:

Hardware is all hardware except software, which is the most vulnerable to destruction or theft, and its secure access control function is relatively weak. Information or data is transmitted between hosts or between hosts and terminals and networks through communication lines, and may also be intercepted during transmission.

3.Environmental factors:

Electromagnetic radiation: computer equipment itself has the problem of electromagnetic radiation, and it is also afraid of the radiation and interference of external electromagnetic waves, especially its own radiation carries information, which is easy to be received by others, resulting in information leakage.

Ancillary support system: Interruption or abnormal operation of water, electricity, and air conditioning will affect the operation of the system.

Natural factors: fire, electricity, water, static electricity, dust, harmful gases, **, lightning, strong magnetic fields and electromagnetic pulses and other hazards. Some of these hazards can damage system equipment, while others can damage data or even destroy the entire system and data.

4.Human Factors:

The level of safety management is low, the technical quality of personnel is poor, operation errors or mistakes, and illegal and criminal acts.

5.Data Entry Section:

The data is processed through the input device input system, and the data is susceptible to tampering or false data input.

6.Data Output Section:

The processed data is converted into human-readable files and output through a variety of output devices, where the information can be leaked or stolen in the process.

The security threats faced by computer networks can be roughly divided into two types: one is the threat to the network itself, and the other is the threat to the information in the network. Threats to the network itself, including threats to network equipment and network software system platforms; Threats to information in the network include not only threats to the data in the network, but also threats to the information system application software that processes these data.

There are many factors that affect the security of computer networks, and the threats to network security mainly come from three factors: unintentional mistakes, malicious attacks, vulnerabilities and "backdoors" of network software systems.

Unintentional human error is an important cause of network insecurity. Network administrators are under increasing pressure in this regard. A little ill-thought and improper security configuration can lead to security breaches.

In addition, users do not have a strong sense of security, do not operate in accordance with security regulations, such as careless password selection, and transfer their accounts to others or share them with others, which will bring threats to network security.

Malicious attacks by humans are the biggest threat to computer networks today. Human attacks can be divided into two categories: one is active attacks, which selectively undermine the validity and integrity of systems and data in various ways; The other type is passive attack, which is to intercept, steal, and decipher important confidential information without affecting the normal operation of the network and application system.

Both of these attacks can cause great harm to computer networks, resulting in network disruption or confidential leakage.

A network software system cannot be 100% defect-free and bug-free. In addition, many software programs have "backdoors" that are set up by designers and programmers for convenience. These vulnerabilities and "backdoors" are precisely the prime targets for hackers to carry out attacks.

Interactivity is not included.

The five basic elements of information security are to ensure the confidentiality, authenticity, integrity, availability and non-repudiation of information.

Encryption is a common means of achieving confidentiality requirements when data content is required to be protected from leakage.

It is a characteristic of information security since its birth, and it is also one of the main research contents of information security. More colloquially, it means that unauthorized users are not able to obtain sensitive information.

For paper document information, we only need to protect the document from unauthorized access. For information in the computer and network environment, it is necessary not only to prevent unauthorized persons from reading the information. It is also necessary to prevent authorized persons from passing on the information they have accessed to non-authorized persons to the extent that the information is leaked.