Before talking about network adapters for local networks , you need to decide what a network is. The term, which has come into use and is found in everyday practice very often, implies the presence of a certain group of computers, which, using special equipment, are interconnected into a single functional and informational whole. This connection can be direct (point-to-point) or using additional communication nodes.

Networks can be of different types. A local network is a network association of several computers within a certain limited space (it can be an apartment, office, business center, industrial premises). Within the framework of the local network, the interaction of computers and programs is provided.

To provide building a local network different types of network equipment. One of the most important types of such equipment is a network adapter (network card). The main task of a network adapter within a local network is to connect a computer and a network cable. The adapter converts the information to be sent into special packets. The packets themselves are nothing more than some logical articulation of data that allows direct information to be forwarded from the source address to the destination of this data.
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The so-called MAC address is built into the chip of any network card. This is a physical address enabling the handling of media access.

If we talk about a certain functional and operational sequence of actions of a network adapter, then we can distinguish:

Receiving information from the operating system and converting it into electrical signals for further transmission over the cable.

Receiving electrical signals over a cable and converting them back into data that the operating system can work with,

Determining whether the received data packet is intended for this particular computer,

Controlling the flow of information that passes between a computer and a network.

Installing the network adapter(correct installation) assumes a certain level of knowledge and understanding of the logic of actions. per century information technologies you can find a lot of information on the same Internet. However, nothing can replace direct experience. network adapter installation.

Our specialists service center have rich experience building local networks different levels and configurations, installing network cards (network adapters) any kind. Turning to our company, you can fully rely on the qualifications and professionalism of our employees.

Recently my hospital started to gently have my brains with a permanent yellow triangle in the corner of the screen with the comment: The network adapter "LAN connection" does not have valid IP settings. All this happened to me Windows system 7 Ultimatum x32 (and later on x64).
In general, I will tell you about possible reasons and how to get rid of them.

Part 1. Reasons.

In order to decide right away and not read a lot of unnecessary letters in this topic, I will divide it into paragraphs like this:
1 - The problem arose when buying a "fresh" laptop.
2 - The problem arose after using your machine and network cable for a long time, respectively.
3 - The problem arose after changing the provider. (It happens if it’s not worth it ... At the provider. (Joke, of course). If you don’t have a check mark when automatically changing network settings, then it’s probably worth checking it? Also, if there is installation disk for the modem, we use it. It will set up your network as it should.)

Part 2. Consequences.

Let me explain a little about the above.

Options for number 1: The quality of the connector crimp, the quality of the connection in the network adapter, Windows is not friendly with your network card (this is rare, but it happens)
Options for #2: Connector crimp quality only. Less often - a network card socket (It is almost impossible to gouge it)
Options for #3: Settings network connection when switching to a new provider, they remained old. (This can happen if the setting is not checked for " Automatic update settings").

Part 3. How to treat.

Treat #1:

1.1) Let's start with a simple and understandable way for any "lamo": if something is not clear, rearrange the "Windows". This method is not always effective, because it can be not only in some settings or in the registry that you do not understand, but, for example, in a bad network cable.
1.2) Reset tcp/ip protocol settings to default using avz

Treat #2:

2.1) If you dig deeper, you can open the settings of our network connection in the "Network Control Center". But without a solid experience, I advise you not to go there and not poke anything there, because you can be smart so that later the specialist will rake it with great difficulty.
2.2) Everything is made much simpler: look at the network connection indicator on the network card. If the green LED lights up steadily and the orange LED blinks nearby, the option with a damaged power cord disappears immediately.
2.3) It is also possible that you connect to the provider's network, which authorizes clients by MAC address, and the laptop has a different MAC. In this case, you need to register the MAC manually and everything will work.
2.4) In the Windows Vista/7 operating system, the BROADCAST flag is added to DHCP packets, which may not be processed by all devices.
To solve this problem, it is proposed to disable the DHCP BROADCAST flag by editing the registry.

Treat #3:

3.1) Either your network assigns IP manually, or you have a problem with the cable (wrong crimp or break). You should register the IP manually (if you know which one), or check the box to automatically change the parameters.
3.2) When connecting 3 conductors out of 4 required Windows recognizes the cable as connected, so double-check your network cable.

If the network cable is in order and we do NOT want to be treated:
in CMD under administrator rights, enter: netsh winsock reset , reboot the system. After reboot: netsh ip reset

You may need to set up the network again. Before starting, do not forget to overwrite the network settings.

If all of the above methods did not help, contact a specialist at the service center computer technology, most likely you will be offered to change the network card / network cable.

ZY: I solved "my" trouble by a banal replacement of a damaged power cord. From the symptoms of a past illness: After starting the computer, the Internet works fine, and after a few minutes it loses connection from the cable and a sign appears from the name of the topic. Thank you all, bye bye. Bye =)

@music: Al Bizzare - Record Club # 22 (05-09-2012)

Network, where is it located and how does it work? These are the main questions that will be explored in this article.

Why is it needed?

The adapter is the equipment that ensures the functioning of the network at the data link and physical layers. It is classified as a peripheral. It interacts directly with the data transmission medium. The adapter successfully solves the problem of reliable overflow of binary data over external communication lines. Since it is a computer controller, it performs its work under the control of a driver installed in the operating system. The network adapter is mounted in the socket of the motherboard. It converts the parallel codes that are used in the computer into a stream of powerful signals that transmit data over the network. Therefore, they are required to be compatible with the network operating system and the information bus of the PC itself. How to install a network adapter in the motherboard?

Setting

We have analyzed what a network adapter is, now we can consider its preparation for work. If it complies with the PnP standard, then the configuration is automatic. Otherwise, you must manually work with the interrupt request line and the I / O address.

Functions

We looked at what a network adapter is and how it is configured, but now let's talk about the tasks that are solved when sending or receiving messages. There are nine in total:

1. Conducted with or Basically, pulse transformers are used for this purpose, although optocouplers can also be used.
2. Transmission (reception) of data. They come from RAM to the adapter or from it to the computer's memory thanks to I / O channels and direct access.
3. Buffering. Used to match the rate at which data is sent from or to the adapter to how it is transmitted over the network. Also, during information processing, it is stored in a buffer. It allows the adapter to work with the entire package of information. Also, thanks to the adapter, the data processing speeds of the various components of the LAN are coordinated with each other.
4. Packet formation. The network adapter must divide the data into separate blocks in the transmission mode (or they are collected when receiving), in order to then arrange them as a frame of a certain format. It will be composed of several service fields, where the address of the recipient's computer is indicated, as well as the frame checksum, according to which the device makes a conclusion about whether the delivered information is correct.
5. Access to Also in his "jurisdiction" is a set of rules with which you can get the opportunity to work with the transmission medium. In addition, the adapter detects conflict situations and monitors the state of the network.
6. Identification of your address in the packet that is received. It can be determined by setting switches, flashed in EPROM, or stored in a special register.
7. Convert parallel code to serial when transmitting data, and it reverse converts it when receiving it. There is a small exception to this. When the data transfer mode is active, the information is transmitted over the communication channel in a serial code.
8. Encoding / decoding data. At this stage, electrical signals are generated that are used to represent information. In most cases, Manchester coding is used. This method does not require a clock signal to be transmitted in order to recognize 1s and 0s. In this case, polarity reversal is used.
9. Reception or transmission of data pulses.

Also, network adapters when working with the necessary software can recognize and process an error that occurs due to poor hardware performance, collisions, or electrical interference.

Base address

Also called physical. Some network adapters can use RAM computer as a buffer to store outgoing and incoming data packets.

The base address in this case is a hexadecimal number that indicates where the information is located.

Classification by protocol access methods and media

There are three main types of adapter used:

1. ethernet.
2. FDDI.
3. token ring.

Usually a certain model runs only on its own network technology. But at the same time they can support, as a rule, several different data transmission media.

For example, Ethernet works with:

1. Unshielded twisted pair.
2. coaxial cable.

When a device must operate in a medium for which it was not originally intended, converters and transceivers are used. Network adapters are also distinguished by the internal data bus:

1. EISA.

By what parameters can network adapters be classified?

In addition to the above, the following can also be used:

1. Tire type.
2. The size of the buffer for the packet.
3. Transmission speed.
4. Compatible with different microprocessors.
5. Bus speed.
6. By the presence / absence of the use of direct memory access.
7. Connector design.
8. Addressing of output/input ports and interrupt requests.

Physical implementation

Let's take a network adapter for Windows 7 as an example. For the most part, they can be placed on motherboard. But the TP-Link network adapter is out of bounds system block.

This is not least due to its functionality (the ability to connect multiple computers and create WiFi networks, that is, it also performs the function of a router and a router). The latter feature allows the adapter to create even a small local network that unites all devices with the necessary interface within the radius of accessibility. You can also find a USB network adapter. It is usually offered to people by mobile network operators. The USB network adapter in this case looks like a USB flash drive, and it is connected in the same way. For data transfer, 2G or 3G Internet is used. These are the guises in which we can see a network adapter for Windows 7. By the way, how is this device implemented in laptops? If we talk about the Asus network adapter, then it must be present in the devices. The same applies to other laptops. The fact is that they are designed for use in various conditions, including mobile ones, when you have to work with everything.

Conclusion

So, we found out what a network adapter is, what types they are and how they are implemented in practice.

We also looked at an example of creating a local network with their help. In conclusion, it should be said that they can be found not only on home computers or laptops, but also on the servers of providers that provide Internet access to their users. Only here they are used as a transitional gateway.