You can have "killer" content, but if it is loaded for a long time on the user's device, its value is close to zero. According to the American company Akamai (the leader in the CDN market), every second user expects the website to load for 2 seconds, otherwise it leaves the site.

CDN technology is designed to help a web resource deliver content to end users as fast as possible without resorting to additional investments in network infrastructure.

In this post, Alexey Sechkin, CDN Development Manager, and Evgeny Denisov, CDN Marketing Manager at MegaFon PJSC, talk about the benefits of using content delivery acceleration technologies for all types of websites.
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CDN in the world

The CDN (Content Delivery Network) is a geographically distributed hardware and software platform that optimizes (speeds up) the delivery of digital content to end users of the Internet. Simply put, this is a technology that makes websites and files download faster to the end-user device of the Internet.

Today, the CDN network is experiencing a period of rapid development. According to CISCO forecasts , by 2019 about 62% of the global Internet traffic will be distributed using a CDN.



In Russia, CDN penetration is significantly lower - only 16% in 2014 , which makes it possible to predict the dynamic growth of Internet traffic in Russia, following the rest of the world.

CDN inside: content delivery without traffic jams

How does CDN work? We give a simple analogy. Imagine a unique Moscow fruit shop. On the New Year, everyone traditionally wanted tangerines, and buyers from all over the country from Kaliningrad to Vladivostok followed them to Moscow.

Obviously, there will be first buyers who will receive their mandarins right away, and the last, to which the queue will reach very soon. The roads to the store will be overloaded with traffic jams due to the influx of people who want to get fruit, and the employees of the vault will run around the building in unsuccessful attempts to deliver the goods to everyone.

As a result, everyone will be disappointed and even annoyed: deprived buyers who do not want to stand in lines and congestion, and sellers who have to work in emergency mode.



What the CDN cloud structure looks like: the source server is like a store, and the content is a commodity for users.

The content source server is our unique store, and customers are Internet users. The CDN technology allows, figuratively speaking, at the moment of increased demand, to promptly deliver mandarins to the nearest point of issue via a dedicated highway (CDN network).

That is, the user, say, from Vladivostok will not have to go for content to Moscow, he will be able to get it faster and more comfortable in his local issuing point. As a result, the roads and the store will not be overloaded, and the goods will be delivered in a quiet mode and on time.

In the same way, the claimed content provider traffic is uploaded to the CDN network and duplicated (cached) in the local nodes of the CDN network. And users are beginning to turn not to the source server, but to the nearest node.

The scope of application of the CDN technology is quite extensive - from mass online broadcasts of top events (Olympiad, World Cup, Eurovision) to the content of small online stores.

How does the MegaFon CDN network work?

We introduced the CDN service into commercial operation in 2012. Today, the “cloud” infrastructure of CDN from MegaFon is one of the largest in Russia. Our network consists of 16 regional nodes from Murmansk to Vladivostok, and also has a connection to traffic exchange points (Internet Exchange) in 8 cities to provide better connectivity with networks of regional broadband access network operators.


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Due to the geographically distributed CDN-network of MegaFon, the digital signal delay time (Round Trip Delay indicator, RTD) during the traffic delivery will be reduced. Why is this indicator so important?

The reason why RTD is so crucial is that, due to the specifics of the operation of IP networks, it directly depends on how much traffic (mega, gigabyte, terabyte) can be transmitted per unit of time.

Below are the calculations of the effect of RTD on the download speed of the same file ( source ):

Indicator	Characteristics depending on the route
Delay, ms	one	15	75	130	334
Circular delay, ms	2	thirty	150	260	668
Download time for a file of 5 MB	1 sec	9 sec	46 sec	1 min 21 sec	3 min 29 sec
Download time for a 100 MB file	12 sec	3 min 7 sec	15 minutes	27 min	1 h 9 min
Download time for a 1 GB file	2 minutes	31 min	2 h 36 min	4 h 31 min	11 h 35 min

For every 1000 km, the circular natural delay in signal transmission, excluding losses on network equipment, is about 10 milliseconds. In Russia, the parameter of circular delay due to the length of the territory can reach up to 200 milliseconds.

Using a network of cache servers, CDN minimizes the distance between users and content and reduces RTD by a factor of 10 or more (from 200 ms to <20 ms).


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Our practice confirms the success of using CDN to improve content penetration into the regions. MegaFon's CDN network supported broadcasts of all rating sports events of recent years: the Olympic Games in Sochi, the World Cup in Brazil, the World Hockey Championship. We broadcast the Olympics and matches of the football championship through our smartphone app "Look +" . Statistics showed that 40% of the load falls on the regional CDN nodes.

The work of CDN on the example of real cases

To understand what effect is possible as a result of the work of CDN, we can give an example of using the MegaFon CDN technology for large projects.

In August 2014, one of the world's largest free-to-play MMO and near-game services developers was connected to the MegaFon CDN infrastructure.

For six months, players downloaded about 7,304 petabytes through the MegaFon CDN network. These were mostly periodical updates of the game.

The use of CDN made it possible to increase the number of unique visitors to a web resource in Russia on average per hour by 16%, and the peak number of users by a record 47% to 300 thousand people per hour. Already in the first month of operation, only 1.5% of all traffic was downloaded from the source server - about 12 terabytes: the rest of the load was taken over by CDN servers throughout Russia. After a while, this figure dropped further: in May 2015, only 0.2% of traffic was downloaded from the source server - about 1.3 terabytes.

If we talk about regional penetration, then according to statistics, the number of hits increased by an average of 5% in million-plus cities and by 35% in other Russian cities.

Another case is the use in 2015 of a CDN for the NetByNet wireless digital television project by Wifire TV. Thanks to CDN, the start-up delay time has been halved, and the average speed has increased one and a half times.

The possibility of using CDN for small sites

But to say that a CDN will only be in demand for resources with large volumes of traffic means to underestimate the potential of its use. It can play an equally important role for small sites, for example, online stores.

There are numerous studies that prove that the speed of a site’s download for a modern user is a determining factor in shaping their preferences. Not design, not content, but speed.

For example, in studies conducted by Equation Research and Fastcompany, it is stated that the user outflow from the site already begins after a two-second load delay. After 10 seconds, only 20-40% of users remain waiting. At the same time 75% - 77% of visitors, from those who did not wait for the download, go to their competitors



Conversely, if the site loads less than 2 seconds - for him it becomes a competitive advantage.



That is, if the site loading speed is less than two seconds (which can be achieved using a CDN), then the amount of traffic to the site increases by an average of 5%.

CDN in the new year

For those who still doubt the expediency of using CDN, one can cite the following fact. Due to the intense competition in the market over the past three years, the average cost of transferring 1 GB over the CDN network has decreased by a factor of 2-3. At the same time, the cost of foreign data transmission equipment, which is used for the construction of network infrastructure, increased by 1.5-2 times. Everything goes to the fact that next year these trends will continue.

Meanwhile, the New Year is approaching - the time of the massive influx of users. If you own a site, now is the time to test a CDN .

We will connect any resource for free during test use. Accordingly, you will have the opportunity to compare how the site works with CDN and without CDN.

Ask your questions in the comments!