And high data transfer rate. Internet speed - what is it and how is it measured, how to increase the speed of the Internet connection

Claims that his program is able to make the most of Ethernet resources. Due to its own network driver, its own TCP stack and work bypassing the operating system kernel, it is really able to approach the physical limitations of the Ethernet standard.

Masscan scanner developer Robert Graham has published results that demonstrate the real-world performance of his program.

For the scanner, the number of packets sent per second is important. The Ethernet standard requires that there be a 12-byte "silence" period between packets, which determines the end of one packet and the beginning of the next. At the end of each packet, a CRC code (4 bytes) must also be transmitted to check the integrity of the transmission, and at the beginning of the packet, a mandatory preamble of 8 bytes. There is one more restriction - the minimum packet size is 60 bytes, this is an ancient restriction from the 80s, which does not make sense nowadays, but is kept for the sake of compatibility.

Given all the restrictions, then the packets must be at least 84 bytes. Thus, for a 1 Gbps network, we get a theoretical limit of 1,000,000,000/84*8 = 1,488,095 packets per second.

On a modern 10 Gigabit network, this number can be increased tenfold: 14,880,952 packets per second.

When scanning ports, we do not need to use all 60 bytes, 20 bytes for the IP header and 20 bytes for the TCP header are enough, 40 bytes in total. That is, the effective packet rate is 1488095 x 40 = 476 Mbps. In other words, even if we use the physical Ethernet resource at 100%, the provider or the program for measuring traffic on a gigabit channel will show a data transfer rate of 476 Mbps. Such a discrepancy is understandable, because during normal surfing packets of 40 bytes are not used, there packets are usually 500 bytes each, so the overhead from the service data can be ignored.

In practice, the scanner can ignore some Ethernet standards, such as reducing the pause between packets from 12 to 5 bytes, and the preamble from 8 to 4 bytes. Minimum size packet can be reduced from 84 to 67 bytes. In this case, 1,865,671 packets per second can be transmitted over a gigabit channel, which increases the speed demonstrated in tests from 476 Mbps to 597 Mbps. True, unpleasant consequences are possible here: the router on the path of your packets may discard some of them, which will reduce the actual effective data transfer rate.

There are other problems as well. For unknown reasons, Linux is unable to overcome the milestone of 1.488 million packets per second on gigabit Ethernet. On the same system, but with a 10Gb link connected, Linux barely breaks the 2Mpps mark. In practice, the real speed in a Linux system is approximately 1.3 million packets per second on a gigabit link. Again, Robert Graham has no idea why this is.

We live in an era of rapidly developing digital technologies. It is hard to imagine today's reality without personal computers, laptops, tablets, smartphones and other electronic gadgets that do not operate in isolation from each other, but are combined into local network and connected to the global network

An important characteristic of all these devices is the bandwidth of the network adapter, which determines the data transfer rate in a local or global network. In addition, the speed characteristics of the information transmission channel are important. In electronic devices of the new generation, it is possible not only to read text information without failures and freezes, but also to comfortably play multimedia files (pictures and photos in high resolution, music, video, online games).

How is data transfer rate measured?

To determine this parameter, you need to know the time for which the data was transmitted, and the amount of information transmitted. Over time, everything is clear, but what is the amount of information and how can it be measured?

In all electronic devices, which are essentially computers, the stored, processed and transmitted information is encoded in the binary system by zeros (no signal) and ones (there is a signal). One zero or one unit is one bit, 8 bits are one byte, 1024 bytes (two to the tenth power) is one kilobyte, 1024 kilobytes is one megabyte. Next come gigabytes, terabytes, and larger units. These units are usually used to determine the amount of information stored and processed on any particular device.

The amount of information transmitted from one device to another is measured in kilobits, megabits, gigabits. One kilobit is a thousand bits (1000/8 bytes), one megabit is a thousand kilobits (1000/8 megabytes) and so on. The speed at which data is transmitted is usually indicated in the amount of information passing in one second (the number of kilobits per second, megabits per second, gigabits per second).

Telephone line data rate

Currently, to connect to the global network via a telephone line, which was originally the only channel for connecting to the Internet, ADSL modem technology is predominantly used. It is able to turn analog telephone lines into high-speed data transmission facilities. The Internet connection reaches a speed of 6 megabits per second, and the maximum data transfer rate over a telephone line according to ancient technologies did not exceed 30 kilobits per second.

Data transfer rate in mobile networks

The 2g, 3g and 4g standards are used in mobile networks.

2g came to replace 1g due to the need to switch the analog signal to digital in the early 90s. On mobile phones that supported 2g, it became possible to send graphic information. The maximum data transfer rate of 2g exceeded 14 kilobits per second. In connection with the advent of mobile Internet, a 2.5g network was also created.

In 2002, the third generation network was developed in Japan, but mass production mobile phones with 3g support started much later. The maximum data transfer rate over 3g has grown by orders of magnitude and reached 2 megabits per second.

Owners of the latest smartphones have the opportunity to take full advantage of the 4g network. Its improvement is still ongoing. It will allow people living in small settlements, freely access the Internet and make it much more profitable than connecting from stationary devices. The maximum data transfer rate of 4g is simply huge - 1 gigabits per second.

To the same generation as 4g, lte networks belong. The lte standard is the first, earliest version of 4g. Consequently, the maximum data transfer rate in lte is significantly lower at 150 megabits per second.

Data rate over fiber optic cable

The transmission of information over fiber optic cable is by far the fastest in computer networks. In 2014, scientists in Denmark achieved the maximum data transfer rate over fiber optics of 43 terabits per second.

A few months later, scientists from the US and the Netherlands demonstrated a speed of 255 terabits per second. The magnitude is colossal, but it is far from the limit. In 2020, it is planned to achieve 1000 terabits per second. The speed of data transmission over fiber optics is practically unlimited.

Wi-Fi download speed

WiFi - trademark, denoting wireless computer networks, united by the IEEE 802.11 standard, in which information is transmitted over radio channels. Theoretically, the maximum data transfer rate of wifi is 300 megabits per second, but in reality, best models routers, it does not exceed 100 megabits per second.

The advantages of Wi-Fi are the ability to wirelessly connect to the Internet using one router for several devices at once and the low level of radio emission, which is an order of magnitude less than that of cell phones at the time of their use.

In the case of the speed of information transfer, these “beautiful numbers” are confusing. Of course, here the situation is still different - this is a confusion between the standard (where the speed is named according to what it is at the link level) and reality, but the meaning is very similar: the number on the sticker does not correspond to what you see with your eyes when you turn on the computer. It is with this confusion that we will try to sort it out.

There are two types of connection - using a cable, and over the air, wirelessly.

Cable connection.

In this case, there are fewer problems with numbers. Connection occurs at a speed of 10, 100 or 1000 megabits (1 gigabits) per second. This is not “internet speed”, not the speed of opening pages or downloading files. This is only the speed between the two points that such a cable connects. From your computer, the cable can go to the router (modem), to another computer or to the entrance, to the provider's equipment, but in any case, this speed only indicates that the connection between these two points took place on specified speed.

Data transfer speed is limited not only by the type of cable, but also quite severely by the speed of your hard drive. On a gigabit connection, the file transfer speed will rest against this, and it is possible to achieve real 120 megabytes per second only in some cases.

The connection speed is selected automatically depending on how your connected devices “negotiate”, according to the slowest of them. If you have a gigabit network card (and most of them are now in computers), and at the other end - 100 megabit equipment, then the connection speed will be set to 100mbit. No additional speed settings need to be made if required - this is an indicator that there is a problem with the cable, or with the equipment you have or at the other end, and therefore the maximum speed is not automatically set.

Wireless connection.

But with this type of connection, there are much more problems and confusion. The point is that at wireless connection the data transfer rate is approximately two times less than the standard figure says. How it looks in real data - look at the table.

Standard	Frequency and bandwidth	Standard speed	Real file transfer speed	Additional Information
WiFi 802.11 a	5Ghz. (20MHz)	54 mbit/s		Currently, it is rarely used in household equipment, it is found in provider networks.
WiFi 802.11 b	2.4Ghz(20Mhz)	11 mbit/s	OK. 0.6 megabytes (4.8 megabits) per second	Currently only used for computer-to-computer (Ad-Hoc) communications
WiFi 802.11 g	2.4Ghz(20Mhz)	54 mbit/s	OK. 3 megabytes (24 megabits) per second	By far the most common type of connection.
WiFi 802.11 n	2.4Ghz/5Ghz(20Mhz/40Mhz)	150, 300, 600mbit/s	5-10 megabytes per second.	Conditionally 1 stream (antenna) - 150 megabits, router (network) with 4 antennas supports 600mbps

As you can see, everything is very sad and ugly, and the vaunted “N” does not show the numbers that I would like to see at all. In addition, this speed is provided under the conditions environment, close to ideal: no interference, no metal walls between the router and the computer (line of sight is better), and the smaller the distance, the better. In a typical three-room apartment of a reinforced concrete house, a wireless access point installed in the far part of the apartment can be almost imperceptible from the opposite part. The “N” standard provides the best coverage, and this advantage is more important to me personally than speed; and the high-quality coverage also affects the speed well: where the data transfer rate when using equipment with “G” is 1 megabit, only using “N” can increase it several times. However, it is not at all a fact that this will always be the case - the matter is in the ranges, in some cases such switching does not give a result.

The speed is also affected by the performance of the device distributing the Internet (router, access point). With the active use of torrents, for example, the data transfer speed through the router can drop significantly - its processor simply cannot cope with the data flow.

The selected type of encryption also affects the speed. From the name itself, it is clear that “encryption” is the processing of data in order to encode it. Different encryption methods can be used, and hence the different performance of the device that this encryption-decryption performs. Therefore, it is recommended to set in the parameters wireless network WPA2 encryption type is the fastest and most secure on this moment encryption type. As a matter of fact, according to the standard, any other type of encryption will not allow “N” to turn on at “full power”, but some Chinese routers spit on the standards.

One more moment. In order to get all the benefits of the N standard (especially for equipment that supports MIMO), the access point must be set to “N Only” mode.

If you have selected “G+N Mixed” (any “mixed” mode), there is a high chance that your devices will try to communicate not at their maximum speed. This is a fee for standards compatibility. If your devices support “N”, forget about the rest of the modes - why waste the benefits offered? Using both G and N equipment on the same network at the same time will deprive you of them. However, there are routers that have two transmitters and allow you to work in two different frequency ranges at the same time, but this is rather rare, and their price is much higher (for example, Asus RT-N56U).

Other connection types.

In addition to those described, of course, there are other types of connection. Outdated option - connection via coaxial cable, an unusual connection option through the building's electrical network, many connection options using mobile networks - 3G, new LTE, relatively uncommon WiMAX. Any of these connection types has speed characteristics, and any of them operates with the concept of “speed TO”. You are not being deceived (well, formally they are not being deceived), but it makes sense to pay attention to these numbers, understanding what they mean in reality.

Units.

There is confusion caused by the misuse of units of measure. Probably, this is a topic for another article (on networks and connections, which I will write soon), but still, here (compressed) it will be in place.

In the computer world, the binary number system is adopted. The smallest unit of measure is bit. Next is byte.

Ascending:

1 byte = 8 bits

1024 bits = 1 kilobit (kb)

8 kilobits = 1 kilobyte (KB)

128 kilobytes = 1 megabit (mb)

8 megabits = 1 megabyte (MB)

1024 kilobytes = 1 megabyte (MB)

128 megabytes = 1 gigabit (gb)

8 gigabits = 1 gigabyte (GB)

1024 megabytes = 1 gigabyte (GB)

Everything seems to be clear. But! It turns out that there is confusion here as well. Here's what wikipedia says:

When designating the speed of telecommunications connections, for example, 100 Mbps in the 100BASE-TX standard (“copper” Fast Ethernet) corresponds to a transmission rate of exactly 100,000,000 bps, and 10 Gbps in the 10GBASE-X (Ten Gigabit Ethernet) standard - 10,000,000,000 bps.

Who to believe? Decide for yourself, whichever is more convenient for you, read the same Wikipedia. The fact is that what is written on Wikipedia is not the ultimate truth, it is written by people (in fact, anyone can write something there). But in textbooks (in particular, in the textbook “Computer Networks” by Olifer V.G., Olifer N.A.) - the calculus is normal, binary, and in 100 megabits -12.5 megabytes, and you will see exactly 12 megabytes when downloading the file over a 100-megabit LAN, in almost any program.

Different programs display the speed in different ways - some in kilobytes, some in kilobits. Formally, if we are talking about * bytes, a capital letter is put, about * bits, a small letter (designation KB (KB, sometimes kB or kB, or Kbyte)) - means “kilobyte”, kb (kb, or kbit) - “kilobit” , etc.), but this is not a hard-and-fast rule.

- Why do you need nubuck in Reshety?
- To limitlessly use the capabilities of the bluetooth, and switch with other subscribers throughout the region of Russia using Wi-Fi!
(C) Ural Pelmeni

The IEEE 802.11 working group was first announced in 1990, and for 25 years now there has been ongoing work on wireless standards. The main trend is the constant increase in data transfer rates. In this article, I will try to trace the path of technology development and show how the performance increase was ensured and what should be expected in the near future. It is assumed that the reader is familiar with the basic principles of wireless communication: modulation types, modulation depth, spectrum width, etc. and knows the basic principles of work WiFi networks. In fact, there are not many ways to increase the throughput of a communication system, and most of them were implemented at different stages of improving the standards of the 802.11 group.

The standards that define the physical layer from the mutually compatible a/b/g/n/ac line will be considered. 802.11af (Wi-Fi at terrestrial television frequencies), 802.11ah (Wi-Fi in the 0.9 MHz band, designed to implement the concept of IoT) and 802.11ad (Wi-Fi for high-speed connection of peripheral devices such as monitors and external drives) are incompatible with each other. with a friend, have various areas applications and are not suitable for analyzing the evolution of data transmission technologies over a long time interval. In addition, the standards that define security standards (802.11i), QoS (802.11e), roaming (802.11r), etc., will remain outside of consideration, since they only indirectly affect the data transfer rate. Here and below, we are talking about the channel, the so-called gross speed, which is obviously higher than the actual data transfer rate due to the large number of service packets in radio traffic.

The first wireless standard was 802.11 (no letter). It provided for two types of transmission media: radio frequency 2.4 GHz and infrared range 850-950 nm. IR devices were not widespread and did not receive development in the future. In the 2.4 GHz band, two methods of spreading the spectrum were provided (spreading is an integral procedure in modern systems communications): frequency hopping spread spectrum (FHSS) and direct sequence sequence (DSSS). In the first case, all networks use the same frequency band, but with different algorithms rebuilding. In the second case, frequency channels from 2412 MHz to 2472 MHz with a step of 5 MHz are already appearing, which have survived to this day. The 11-chip Barker sequence is used as the spreading sequence. In this case, the maximum data transfer rate was from 1 to 2 Mbps. At that time, even taking into account the fact that under the most ideal conditions, the useful data transfer rate over Wi-Fi does not exceed 50% of the channel, such speeds looked very attractive in comparison with the speeds of modem access to the Internet.

For signal transmission in 802.11, 2- and 4-position keying was used, which ensured the operation of the system even in adverse signal-to-noise conditions and did not require complex transceiver modules.
For example, to implement an information rate of 2 Mbps, each transmitted symbol is replaced by a sequence of 11 symbols.

Thus, the chip speed is 22 Mbps. For one transmission cycle, 2 bits (4 signal levels) are transmitted. Thus, the keying rate is 11 baud and the main lobe of the spectrum at the same time occupies 22 MHz, a value that, in relation to 802.11, is often called the channel width (in fact, the signal spectrum is infinite).

In this case, according to the Nyquist criterion (the number of independent pulses per unit time is limited by twice the maximum channel bandwidth), a bandwidth of 5.5 MHz is sufficient to transmit such a signal. Theoretically, 802.11 devices should work satisfactorily on channels separated by 10 MHz (as opposed to later implementations of the standard, which require broadcasting at frequencies spaced at least 20 MHz apart).

Very quickly, speeds of 1-2 Mbps were not enough and 802.11 was replaced by the 802.11b standard, in which the data transfer rate was increased to 5.5, 11 and 22 (optional) Mbps. The increase in speed was achieved by reducing the redundancy of error-correcting coding from 1/11 to ½ and even 2/3 due to the introduction of block (CCK) and high-precision (PBCC) codes. In addition, the maximum number of modulation steps has been increased to 8 per transmitted symbol (3 bits per 1 baud). The channel width and frequencies used have not changed. But with a decrease in redundancy and an increase in the depth of modulation, the requirements for the signal-to-noise ratio inevitably increased. Since it is impossible to increase the power of the devices (due to energy savings mobile devices and legislative restrictions), this limitation manifested itself in a slight reduction in the service area at new speeds. The service area at legacy speeds of 1-2 Mbps has not changed. From the method of spreading the spectrum by frequency hopping, it was decided to completely abandon. It was no longer used in the Wi-Fi family.

The next step in increasing the speed to 54 Mbps was implemented in the 802.11a standard (this standard began to be developed earlier than the 802.11b standard, but the final version was released later). The increase in speed was mainly achieved by increasing the modulation depth to 64 levels per symbol (6 bits per 1 baud). In addition, the RF part has been radically revised: the direct sequence spread spectrum has been replaced with the spread spectrum by splitting the serial signal into parallel orthogonal densifiers (OFDM). The use of parallel transmission on 48 subchannels made it possible to reduce intersymbol interference by increasing the duration of individual symbols. Data transmission was carried out in the 5 GHz band. The width of one channel is 20 MHz.

Unlike the 802.11 and 802.11b standards, even partial overlap of this band can result in transmission errors. Fortunately, in the 5 GHz band, the distance between channels is these same 20 MHz.

The 802.11g standard was not a breakthrough in terms of data transfer speed. In fact, this standard became a compilation of 802.11a and 802.11b in the 2.4 GHz band: it supported the speeds of both standards.

However, this technology requires high quality manufacturing of the radio part of the devices. In addition, these speeds are fundamentally unrealizable on mobile terminals (the main target group Wi-Fi standard): the presence of 4 antennas at sufficient separation cannot be implemented in small-sized devices, both for reasons of lack of space and due to the lack of energy sufficient for 4 transceivers.

In most cases, 600 Mbps is no more than marketing ploy and unrealizable in practice, since in fact it can only be achieved between fixed access points installed within the same room with a good signal-to-noise ratio.

The next step in transmission speed has been taken by the 802.11ac standard: the maximum speed provided by the standard is up to 6.93 Gb / s, but in fact this speed has not yet been achieved on any equipment on the market. The increase in speed is achieved by increasing the bandwidth up to 80 and even up to 160 MHz. Such a band cannot be provided in the 2.4 GHz band, so the 802.11ac standard operates only in the 5 GHz band. Another factor in increasing the speed is an increase in the modulation depth to 256 levels per symbol (8 bits per 1 baud). Unfortunately, such a modulation depth can only be obtained near the point due to the increased requirements for the signal-to-noise ratio. These improvements made it possible to achieve an increase in speed up to 867 Mbps. The rest of the increase comes from the previously mentioned 8x8:8 MIMO streams. 867x8=6.93 Gbps. MIMO technology has been improved: for the first time in the Wi-Fi standard, information on the same network can be transmitted to two subscribers simultaneously using different spatial streams.

In a more visual form, the results in the table:

The table lists the main ways to increase throughput: "-" - the method is not applicable, "+" - the speed was increased due to this factor, "=" - this factor remained unchanged.

Resources for redundancy reduction have already been exhausted: the maximum error-correcting code rate 5/6 was achieved in the 802.11a standard and has not been increased since. Increasing the modulation depth is theoretically possible, but the next step is 1024QAM, which is very demanding on the signal-to-noise ratio, which will ultimately reduce the range of the access point at high speeds. At the same time, the requirements for the performance of the hardware of the transceivers will increase. Reducing the inter-symbol guard interval is also unlikely to be the direction of speed improvement - its reduction threatens to increase errors caused by inter-symbol interference. An increase in the channel bandwidth beyond 160 MHz is also hardly possible, since the possibilities for organizing non-overlapping cells will be severely limited. An increase in the number of MIMO channels looks even less realistic: even 2 channels are a problem for mobile devices (due to power consumption and dimensions).

Of the listed methods for increasing the transmission rate, most of them take the useful coverage area as a retribution for their use: the bandwidth of the waves decreases (transition from 2.4 to 5 GHz) and the requirements for the signal-to-noise ratio increase (increase in modulation depth, increase in code speed). Therefore, in their development, Wi-Fi networks are constantly striving to reduce the area served by one point in favor of the data transfer rate.

As available areas of improvement, the following can be used: dynamic distribution of OFDM subcarriers between subscribers in wide channels, improvement of the medium access algorithm aimed at reducing service traffic and the use of interference compensation techniques.

Summing up the above, I will try to predict the development trends of Wi-Fi networks: it is unlikely that in the following standards it will be possible to seriously increase the data transfer rate (I don’t think that more than 2-3 times), if there is no qualitative leap in wireless technologies: almost all the possibilities quantitative growth exhausted. It will be possible to meet the growing needs of users in data transmission only by increasing the coverage density (reducing the range of points due to power control) and by more rational distribution of the existing bandwidth between subscribers.

In general, the trend of shrinking service areas seems to be the main trend in modern wireless communications. Some experts believe that LTE standard has reached the peak of its capacity and will not be able to develop further for fundamental reasons related to the limited frequency resource. Therefore, offload technologies are developing in Western mobile networks: at any opportunity, the phone connects to Wi-Fi from the same operator. This is called one of the main ways to save the mobile Internet. Accordingly, the role of Wi-Fi networks with the development of 4G networks not only does not fall, but increases. Which poses more and more high-speed challenges to technology.

With the passage technical progress the possibilities of the Internet have expanded. However, in order for the user to take full advantage of them, a stable and high-speed connection is required. First of all, it depends on the bandwidth of the communication channels. Therefore, it is necessary to find out how to measure the data transfer rate and what factors affect it.

What is the bandwidth of communication channels?

In order to get to know and understand new term, you need to know what a communication channel is. If to speak plain language, communication channels are devices and means by which transmission is carried out at a distance. For example, communication between computers is carried out thanks to fiber optic and cable networks. In addition, a method of communication over a radio channel is common (a computer connected to a modem or a Wi-Fi network).

Bandwidth is the maximum speed of information transfer in one specific unit of time.

Typically, the following units are used to denote throughput:

Bandwidth measurement

Bandwidth measurement is a rather important operation. It is carried out in order to accurate speed internet connections. The measurement can be carried out using the following steps:

• The simplest is to download a large file and send it to the other end. The disadvantage is that it is not possible to determine the accuracy of the measurement.
• In addition, you can use the speedtest.net resource. The service allows you to measure the width of the Internet channel "leading" to the server. However, this method is also not suitable for a holistic measurement, the service provides data on the entire line to the server, and not on a specific communication channel. In addition, the object being measured does not have access to global network Internet.
• The optimal solution for measuring will be the Iperf client-server utility. It allows you to measure the time, the amount of data transferred. After the operation is completed, the program provides the user with a report.

Thanks to the above methods, you can easily measure real speed internet connections. If the readings do not meet current needs, then you may need to consider changing providers.

Bandwidth calculation

In order to find and calculate the throughput of a communication line, it is necessary to use the Shannon-Hartley theorem. It says: you can find the bandwidth of a communication channel (line) by calculating the mutual relationship between the potential bandwidth, as well as the bandwidth of the communication line. The formula for calculating throughput is as follows:

I=Glog 2 (1+A s /A n).

In this formula, each element has its own meaning:

• I- stands for the maximum throughput setting.
• G- parameter of the bandwidth intended for signal transmission.
• A s/ A n- ratio of noise and signal.

The Shannon-Hartley theorem suggests that to reduce external noise or increase signal strength, it is best to use a wide data cable.

Signal transmission methods

To date, there are three main ways to transmit a signal between computers:

• Radio transmission.
• Data transmission by cable.
• Data transmission via fiber optic connections.

Each of these methods has individual characteristics communication channels, which will be discussed below.

The advantages of information transmission via radio channels include: versatility of use, ease of installation and configuration of such equipment. As a rule, a radio transmitter is used to receive and method. It can be a modem for a computer or a Wi-Fi adapter.

The disadvantages of this method of transmission include unstable and relatively low speed, greater dependence on the availability of radio towers, as well as the high cost of use ( Mobile Internet almost twice as expensive as "stationary").

The advantages of data transmission over a cable are: reliability, ease of operation and maintenance. Information is transmitted through electric current. Relatively speaking, current under a certain voltage moves from point A to point B. A is later converted into information. Wires perfectly withstand temperature changes, bending and mechanical stress. The disadvantages include unstable speed, as well as deterioration of the connection due to rain or thunderstorms.

Perhaps the most advanced data transmission technology at the moment is the use of fiber optic cable. Millions of tiny glass tubes are used in the design of communication channels of a network of communication channels. And the signal transmitted through them is a light pulse. Since the speed of light is several times higher than the speed of current, this technology has made it possible to speed up the Internet connection by several hundred times.

The disadvantages include the fragility of fiber optic cables. Firstly, they do not withstand mechanical damage: broken tubes cannot transmit a light signal through themselves, and sudden temperature changes lead to their cracking. Well, the increased radiation background makes the tubes cloudy - because of this, the signal may deteriorate. In addition, the fiber optic cable is difficult to repair if it breaks, so you have to completely change it.

The foregoing suggests that over time, communication channels and networks of communication channels are improved, which leads to an increase in the data transfer rate.

Average throughput of communication lines

From the foregoing, we can conclude that communication channels are different in their properties, which affect the speed of information transfer. As mentioned earlier, communication channels can be wired, wireless and based on the use of fiber optic cables. The last type of creation of data transmission networks is the most effective. And its average bandwidth of the communication channel is 100 Mbps.

What is a beat? How is bit rate measured?

Bit rate is a measure of the speed of a connection. Calculated in bits, the smallest units of information storage, for 1 second. It was inherent in communication channels in the era of the “early development” of the Internet: at that time, text files were mainly transmitted on the global web.

Now the basic unit of measurement is 1 byte. It, in turn, is equal to 8 bits. Beginning users very often make a gross mistake: they confuse kilobits and kilobytes. This gives rise to bewilderment when a channel with a bandwidth of 512 kbps does not live up to expectations and gives a speed of only 64 KB / s. In order not to be confused, you need to remember that if bits are used to denote speed, then the entry will be made without abbreviations: bits / s, kbit / s, kbit / s or kbps.

Factors Affecting Internet Speed

As you know, the final speed of the Internet also depends on the bandwidth of the communication channel. Also, the speed of information transfer is affected by:

• Connection methods.

Radio waves, cables and fiber optic cables. The properties, advantages and disadvantages of these connection methods have been discussed above.

• Server load.

The busier the server is, the slower it receives or transmits files and signals.

• External interference.

The strongest interference affects the connection created using radio waves. It's caused cell phones, radio receivers and other radio receivers and transmitters.

• Status of network equipment.

Of course, the connection methods, the state of the servers and the presence of interference play an important role in ensuring high speed internet. However, even if the above indicators are normal, and the Internet has a low speed, then the matter is hidden in the network equipment of the computer. Modern network cards capable of maintaining an Internet connection at speeds up to 100 Mbps. Previously, cards could provide a maximum throughput of 30 and 50 Mbps, respectively.

How to increase internet speed?

As mentioned earlier, the bandwidth of the communication channel depends on many factors: the connection method, server performance, the presence of noise and interference, as well as the state of network equipment. To increase the connection speed in a domestic environment, you can replace network equipment with more advanced ones, as well as switch to a different connection method (from radio waves to cable or fiber optics).

Finally

As a summary, it is worth saying that the bandwidth of the communication channel and the speed of the Internet are not the same thing. To calculate the first value, you must use the Shannon-Hartley law. According to him, noise can be reduced, as well as signal strength can be increased by replacing the transmission channel with a wider one.

Increasing the speed of the Internet connection is also possible. But it is carried out by changing the provider, changing the connection method, improving network equipment, as well as fencing devices for transmitting and receiving information from sources that cause interference.