Officials are boosting the speed of data transmission with the rise of ADSL technology

With local ADSL technology The speed of data transmission is always less than the speed of connection by at least 13-15%. This technological exchange, About what we have given in the report. It does not lie with the provider, nor with the modem that is being victorious.
Ideally, the speed of a 12 Mbit/s connection can be upgraded to a maximum real speed of ~10 Mbit/s.

In fact, in addition to technological exchange, there are still very few factors that reduce transmission fluidity. These factors are discussed further.

ADSL technology(Asymmetric Digital Subscriber Line) - asymmetric data transmission technology in which the available channel bandwidth is divided between output channels ( Upload) and enter ( Download) Traffic is asymmetrical. Thus, when connecting to an ADSL modem, the subscriber’s bandwidth is determined ( Upload) that speed to the subscriber ( Download).
In ADSL data transfer rates, connection speed varies depending on Megabits per second (Mbit/s) or in Kilobits per second (Kbit/s) .
For example : numbers 768/10240 talk about those that the maximum output speed of the connection per subscriber becomes 768 Kbps (the speed with which data must be transferred from your local computer to a remote server), and the maximum input speed of the connection to the warehouse subscriber 10240 Kbps (swedishness, with which tribute must be paid to your local computer).
In this case, the maximum speed for attached files (the speed of attachment) becomes ~ 1000 Kilobytes per second (KB/sec).
This figure is derived from the following formula:
connection speed (10240) - 15% (1500)/8 (to convert kilobits to kilobytes).

On the right is that Internet browsers or download/display managers show the speed of transmission to Kilobytes per second .
For example, in the browser Internet Explorer The content of the file is displayed in the field Transmission speed (Transfer rate): xxx KB/sec (KB/Sec).
Browsers and/or download managers use this figure to estimate the speed of transmission in order to extract the last time the file is downloaded. We apologize for the fact that due to a number of reasons, the speed of data transmission is displayed inaccurately. For example, data can be buffered (whereby timers are started with a slight delay, which can lead to incorrect readings). Also, transmission speed may depend on the productivity of the computer.

Let's take a closer look at the factors that contribute to the real liquidity of the connection:

• As a transport protocol, communication equipment (IP ADSL switches) uses vicoristic technology ATM(Asynchronous Transfer Mode – asynchronous method of data transfer). ATM is a moderately high-productivity technology of switching and multiplexing, based on data transmission in the form of frames (frames) of a fixed size (53 bytes). As you know, the Internet uses the IP protocol as a communication protocol, or TCP/IP protocol. ADSL technology as a transport protocol is based on ATM, and data is transmitted over an ADSL line using TCP/IP via ATM. Tobto. IP frames are packaged (encapsulated) into ATM boxes and transmitted to DSL lines, and then the receiving owners are again unpacked and the original IP frames are sent out. Large packets will be divided into 48-byte units. If the packet cannot be divided without excess by 48, then a further addition is added so that the entire number of ends is 48 bytes. After dividing the packet into 48-byte packets, a header (5 bytes) is added to the middle that comes out. As a result, there is a reduction in speed equal to 10% of data transfer speed.
• Wikoristannya protocol TCP/IP under the hour of data transmission, the speed decreases by approximately 3% of the transmission speed, because transferred useful information(data) additional service (protocol) information.

  The most important factors indicated are the same technological changes that occurred at the beginning of the statistics. This exchange leads to the fact that the speed of data transmission is always less than the speed of at least 13-15%.

There are also other officials who reduce transmission fluidity.
Theoretically, the browser window or manager is responsible for downloading/requesting the file at the time of downloading and is responsible for the transmission speed, which is calculated according to the formula Connection speed - 15% (cost for TCP/IP and ATM) / 8 (to convert kilobits to kilobytes) However, the fluidity actually appears to be lower, and there are reasons for this:

• Setting up the computer. For example, insufficient memory (virtual/RAM), old processor, unstable robot (crashes) operating system (blue screen) or software security, not enough Have a good time on the hard drive, the presence of bad programs/viruses on the computer.
• Spend packages per hour of data transfer. A large number of expenses are possible on bad lines (connection channels) or when the maximum permissible connection speed is deviated. When packets are wasted when transmitting frames, the TCP/IP protocol marks the daily packet in the original data stream, does not recognize that it has been removed, and then initiates retransmission of the wasted data. The retransmission procedure is carried out up to the following steps. Thus, the TCP/IP protocol, in addition to the important function of controlling and transporting data, for the detection of large packet losses on the line, increases the speed of data transmission. To check the connection to a server on the Internet, you can use the utility ping(Ping). U command line operating system, enter the command ping -t to my_site, for example ping -t www.download.com. Wait 30 seconds and press Ctrl+C to complete the utility. The statistics will indicate the % of package costs. If packet wastage becomes more than 5%, then the productivity of the TCP/IP protocol will be poor during the hour of work from the designated site.
• Re-engineering of the provider's servers and gateways. Rely on the provider's network structure (for example, a lot of gateways) or the low throughput of the provider's output channel. The problem is avoided at the peak of vandalism. The sheer volume of revenue on the server can exceed the maximum of your revenue during the peak year and cause increased work.
• Routing problems can also cause a decrease in speed. If routing problems are detected, packets can be redirected along alternative routes, causing delays in data transfer.
• Violating the PPPoE protocol can result in reduced speed. PPPoE - non-tunnel-resistant hembark protocol The channel level for transmitting PPP frames over Ethernet is largely exploited by DSL services. PPPoE is a resource-intensive protocol, and when transmitting edge data, it can reach the processor. Depending on the implementation of this PPPoE network, you can reduce the maximum speed by up to 5-25%.
• Insufficient (low) productivity of the BRAS (Broadband Remote Access Server) server. Wide Smooth Router remote access(BRAS) routes traffic to the DSL switch (DSLAM) within the Internet provider. BRAS is located in the core of the provider's network and aggregates the provider's connections across the access network. The router supports logical termination of point-to-point (PPP) tunnels. These can be encapsulated PPP over Ethernet (PPPoE) or PPP over ATM (PPPoA) tunnels. BRAS is also an interface to authentication, authorization and traffic systems.
• It is possible to exchange speed for a tariff plan on the BRAS server. A typical exception, if the liquidity of the physical connection is one, and the liquidity of receiving data is exchanged by payment tariff plan.
• When vikoristanna additional service, for example IPTV ( digital television tower), the stream of the received TV channel also takes up a lot of time, which means close to 4 Mbit/s for channels standard permission. The maximum speed of data reception, when using the IPTV service, can be insured using the following formula:
  Connection speed - 15% - IPTV streaming speed.
  For example, connection speed (10240) – 15% (1500) – IPTV stream speed (4000) = 4700 Kbps (587 Kbps).

The high Internet and low bandwidth allowances lead to disruption. It is important for you to know the cause of the problem, so as not to notice that the speed code is too low. To move...

More Internet and the building's capacity is low and the barrier leads to irritation. It is important for you to know the cause of the problem, so as not to notice that the speed code is too low. To increase the fluidity of the connection, it is necessary to know the real value of the throughput capacity. Let's take a look at a number of ways to vibrate and enhance the characteristics of a fence.

Smuga throughput and throughput capacity

We first need to understand the difference between total throughput and throughput. Once you already understand these terms, add a little terpene. Bandwidth is the fixed speed of data transmission that the tenant pays for the Internet service. Throughput - speed of transmission in local measures- home and small business. It is customary to call Internet speed as bandwidth, and internal bandwidth as bandwidth. Example: the theoretical throughput of a router can be 450 Mbit/s, and the throughput of an Internet connection is less than 20 Mbit/s with a minimum of 1 Mbit/s when transferring data to the server.

Dimming and increased transmission

The Internet connection bandwidth can easily be changed by the way of adjustment, as it was assumed, it is supplied by the Internet provider. However, there are ways to optimize and control throughput.

A good, full-featured router can help improve your Internet connection with the ability to manage QoS, which allows you to more efficiently distribute traffic between the Internet and the inner edge of a booth and a small business. After I replaced the five-year-old router with a new dual-band device with QoS, the speed of my Internet connection became a trifle.

Of course, it is not important to maintain the speed of your Internet connection using such Web tools as speedtest.net. Hint: to correctly evaluate the speed of your Internet connection, select your settings at different times during work hours and on weekends.

Variation of bandwidth

All the way to the right is the world of throughput capacity dartless lines. What is bandwidth? dartless link? This is an incredible speed of data transfer between intermediate devices in the middle home measures or networks of small businesses, which are sometimes called flexible connections of local networks (LAN - do not interfere with the high bandwidth of the Internet or WAN, or global networks).

Is the speed of the dartless range going to die out? Why not reduce the speed of dart devices? For example, why can’t we ensure the speed of data transfer between a computer connected via an Ethernet cable to the local network port on the router, and a NAS device also connected to the router?

Because the speed of Internet bandwidth is a fixed value. Most of the current ones laptop computers, desktop PCs and NAS (in fact, practically any computer with an Ethernet port, released over the last five years), most likely, has a dedicated Gigabit Ethernet port. If the router is also equipped with a Gigabit Ethernet port, data transfer between the computer and the router is carried out at gigabit speed – 1000 Mbit/s. Remember that the computer is powerful, old port Fast Ethernet(100 Mbit/s) and you connect via a wired connection to the router with Gigabit Ethernet, then the speed will be 100, not 1000 Mbit/s. The golden rule is that the maximum speed of the connection is not greater, the lower the speed of the best connection.

I protested throughput capacity that shit for everyone droneless routers and NAS devices submitted for testing to the PCMag lab. For routers, I use Ixia's IxChariot tool, which simulates the fluidity of data flows between two edge devices (called endpoints). This is a wonderful tool that allows you to model any type of traffic (for example, VoIP or gaming) and understand how different types The characteristics of the fence are drawn from these data.

However, Ixia is an expensive utility that can take many hours to master. You can reliably estimate the throughput of the network using an additional test, such as Vikorist, if Ixia is not at hand, or home testing.

The axis is so timid. Take two edge devices and connect one of them (called Device 1) wirelessly through your WiFi router. For further help Ethernet cable connect another device (device 2) to one of the local network ports on the router. Prepare the fire pit hemesh folder on device 2, accessible from device 1. If you need to create a folder in Windows Explorer, right-click on it, go to the Sharing tab ( Outside access) and click on the Share button. I created a folder under the name testshare and allowed it permanent access until regional registration Everyone (after verification, you can delete or change permissions safely, but for this test, device 1 needs to allow writing to a separate folder). In device 1, you can view the created folder through Windows Explorer (or install a thin disk). Having changed, what Zagalna folder Device 2 opens on device 1, copy and paste the large file from device 1 to this folder. For this test, I used a video file of 1.5 GB in size. Determine the hour when you need to make a copy. This way you can determine the basic speed of a dartless survey when moving data from one device to another. Let's say copying a 1.5 GB file took 2 minutes. Then it is necessary to withdraw small payments. We must first convert gigabytes to megabytes (I will ask for help from the Web converter www.convertunits.com/from/GB/to/MB). 1.5 GB stores 1536 MB. We need the speed of megabytes per second to convert the data in seconds. The result is: 1536 (MB)/120 (s) = 12.8 MB/s. Then you need to convert megabytes per second to megabits per second. 1 MBit/s (unit of speed for data saving systems) is higher than 8 MBit/s (unit of transfer speed). Reduced: 12.8 · 8 = 102.4 Mbit/s. You can convert the conversion using the additional Web converter www.mediaroad.com/products/speedcheck/free_tools/unit_convert/. Analysis of results

102.4 Mbit/s is a poor bandwidth, especially for a router with a theoretical speed of 300 Mbit/s and devices 1 and 2 with a 2.4 GHz WiFi band. As a rule, garniy result- approximately half of the maximum throughput declared by the router's manufacturer (this figure is achievable in the test environment, subject to any defects; real-life users are not able to achieve this).

You can say this: Windows already shows the fluidity of a dartless circumferential connection" In this case, pay attention to the window that appears on the screen after right-clicking on the small WiFi icon in the lower right corner of the Task Panel and selecting the Status item. It shows the bit frequency of the connection between the PC adapter and the router, which does not indicate the real throughput when transmitting data packets.

Corysno also test file copying in the 5 GHz range. Speed ​​code is likely to increase if the devices are deployed not too far from the WiFi router (the communication range in the 5-GHz range is shorter). In addition, after checking different scenarios, run a copy test to detect the presence of several devices and devices while streaming music or video from a multimedia player. Once you know the basic level, you can figure out how to stream multimedia data and how many users can use Swidcode. Then you can try to increase the throughput by configuring router settings such as QoS.

The first step before optimizing the characteristics of the fence is to review these characteristics. After this, you can proceed to diagnostics and elimination of problems in order to achieve maximum speed.