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Latency, caching and compression


Understanding these and other countless elements in a Web page access is essential to provide a fast service.



Fast hosting

Family Hosting 
Reserve a domain name for your family name, create e-mail addresses for your children!

Professional Hosting 
With dual domain name included, pre-installed resources for Web development and professional Webmail with employee monitoring support. Includes one Web site template of your choice, for free.

Commerce Hosting 
With triple domain names and built-in EV certificate, these hosting accounts have everything you need to start a trusted electronic commerce site on the Internet. Includes two Web site templates of your choice, for free.

Server 
Adding full predictability to your hosting: a full dedicated non-virtual non-cloud* server with its own FQDN* and IP address* adds performance predictability to your site and reduces the chances that your sent e-mail messages are flagged as spam by recipients.

False speed

If you host your Web site on the same ISP that you use to access the Internet, your site will be faster
True, but it will be faster for you and the few users using the same ISP. For all others it will be slower as your ISP's network supports users at home downloading music and other large files at the same time it supports hosting. Its speed will never be as good as a network dedicated exclusively to hosting, like Cynergi's.

Server with a latest generation CPU* with lots of GHz* and lots of Gb* of memory
Marginal improvement. The only thing those features marginally improve is the Web site's response latency*, something that in the vast majority of HTML pages and scripts will be imperceptible. A script should use algorithms* that allow it to return a response to the visitor in less than 1s, so a faster CPU doesn't make a significant difference in that time. And CPU and RAM* memory do not help transmitting data over the network.

Bandwidth with lots of Gbps*
Insignificant after a certain point. Before reaching the visitor's computer, the Web page will be crossing a series of networks that do not belong to the hosting company. The speed at which the user receives the pages is therefore the slowest speed of the networks that are between him and the server. Because the user's ISP supports users at home downloading music and other large files, the slowest network is usually his.


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High speed
hosting


To make a fast Web site you need more than a good server. You need suitable software configuration to take advantage of all opportunities that the protocols offer to optimize speed.

Cynergi's hosting services offer a series of automatic optimizations that do not need your intervention, but that allow a significant improvement of the experience of visiting your Web site.

And how do we do that? By analyzing the entire Web site access process.

[Web site access diagram]

When a user types in a Web site address in his browser*, the request goes from his ISP's router* to the ISP's caching and proxy* systems. If the page is not found there, it needs to be fetched from Cynergi's servers.

First the browser needs to know the server's IP number*. So the browser contacts the ISP's DNS* servers. If they do not have this information, they will in turn contact the world root DNS servers and then our DNS servers to retrieve the IP of the domain the user is trying to access.

Finally, knowing the IP, the browser makes an HTTP* connection to the server hosting your site at Cynergi, identifies its capabilities and requests the page, receiving it in return.

Network
latency


The travel time of data packets* between the user's PC and Cynergi's server hosting your site varies with the number of routers* or "hops" that exist between the two. As a rule of thumb, the greater the distance between the two, the greater the number of hops.

Since during a file transmission each data packet follows one after the other without waiting for feedback, you won't notice a speed difference (in bps*) between a server that is close by and server that is far away.

However, the first data packet of a transmission takes longer to arrive if the server is far away. This delay (called latency) is measured is fractions of a second, but when a page is made out of several files (and most pages include several images and other files), these differences add up to a noticeable delay.

[Data center map]

With our partnership with Rackspace we're able to reduce this latency by hosting your Web site in servers that are very close to your customers.

Data
compression


If you found a way to squeeze a 20kb file into 12kb, transmission would be faster because there would be less data to transmit.

However if you're trying to transmit a 20 page report by fax, you can't only transmit 12 of them and expect the recipient to understand the report. In order to transmit less data you use compression. Compression isn't about making bits "smaller". A bit can't take up any less space than a bit. What you do is eliminate file redundancy.

For instance, in the report you're about to send by fax, you can look for the 100 most used words. You then replace each of them by just two numeric characters with that word's code. At the end of the report you include a "dictionary" with the conversion between numbers and the words you used. Your report would this way take up less pages.

It is this and other similar techniques that occur in computer data compression. In Cynergi's hosting we have automatic compression of all file types that are not already compressed. There is no need for any action on your side. Tests demonstrate that the increased latency by performing real time compression on the server side is insignificant but the reduced transmission time is easily measurable.

Web page
caching


Imagine that you're writing an article about a company's stock prices. At a certain point you need to know the current value of those stocks. So you call your broker to learn them. Two paragraphs ahead you need the same value again to compare it with other companies'.

Do you call your broker again?

Of course not. You find the mental or paper copy of that value and use it. This is much faster than calling your broker again. And if tomorrow you need to write a similar article, then you can call your broker because stock prices have changed since.

This mechanism of keeping local copies of information we know to be valid for a specific period of time we call caching. Caches and proxies are two very old Internet systems that improve a user's browsing experience by reducing the delay of loading a page.

Cynergi fully explores these systems in its standard hosting service configuration, in every step that involves us (DNS and HTTP). The result is a speed increase that can easily be over 1000%. The way we do this is automatic from your point of view and 100% compatible with every Internet access system in existence. Professional users can partially or totally switch off this feature in pages that need to show updated information often (search engines, shopping carts, etc.).

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