Welcome!

Artificial Intelligence Authors: Liz McMillan, Elizabeth White, Yeshim Deniz, Pat Romanski, Kevin Benedict

Related Topics: @DevOpsSummit, Containers Expo Blog, @DXWorldExpo

@DevOpsSummit: Article

Compression: Making the Big Smaller and Faster (Part 1) | @DevOpsSummit #DevOps #WebPerf

The sharing of information in a fast and efficient manner has been an area of constant study and research

Compression: Making the Big Smaller and Faster (Part 1)
By Nilabh Mishra

How important is data compression? The sharing of information in a fast and efficient manner has been an area of constant study and research. Companies like Google and Facebook have spent a lot of time and effort trying to develop faster and better compression algorithms. Compression algorithms have existed since the ’70s and the ongoing research to have better algorithms proves just how important compression is for the Internet and for all of us.

The Need for Data Compression
The World Wide Web (WWW) has undergone a lot of changes since it was made available to the public in 1991. Believe it or not, the copy of the world’s first website can still be browsed here. Back then, webpages were very simple. Today, they are increasingly more complex and there is an evident need to have compression algorithms that are lossless, fast, and efficient.

There are several best practices that help optimize page load times. Here is a blog from that discusses webpage optimization. In this article, we will spend some time understanding the basics of compression and how it works. We will also cover a new type of compression method called “Brotli” in the second part of this blog.

Encoding and Data Compression
Let’s start by understanding what data encoding and compression are:

The word “compression” comes from the Latin word compressare, which means to press together. “Encoding” is the process of placing a sequence of characters in a specialized format that allows efficient data storage as well as transmission. Per Wikipedia: “Data compression involves encoding information using fewer bits than the original representation.

Compression plays a key role when it comes to saving bandwidth and speeding up your site. Modern day websites involve a lot of HTTP requests and responses between the client (the browser) and the server to serve a webpage. With an overall increase in the number of HTTP requests and responses, it becomes important to ensure that these transfers are taking place at a fast and efficient rate.

HTTP works on a request-response model, as demonstrated below:

In this case, we are not using any compression method to compress the response being sent by the server.

  • The browser sends an HTTP request asking for the Index.html page
  • The server looks for the requested file and responds with the requested resource and a 200 OK HTTP status message
  • The browser receives the server’s response and renders the page

As we can see, in this case there is no compression involved. The server responded with a 300 KB file (index.html page). If the file size was bigger, it would have taken more time for the response to be sent on the wire and this would have increased the overall page load time. Please note that we are currently looking only at a single HTTP response. Modern websites receive hundreds of such HTTP responses from the server to render a webpage.

The image below shows the same HTTP request – response between the browser and the server, but in this case, we use compression to reduce the size of the response being sent by the server to the browser.

Today, complex and dynamic websites generate hundreds of HTTP requests/responses. This made it important to have a system which would ensure fast and efficient data transfer between the server and the browser. This is when compression algorithms like Deflate and Gzip came into existence.

Introduction to Gzip
Gzip is a compression method that is used to make files smaller for storage and faster transmission over the network. Gzip is one of the most popular, powerful, and effective ways of compressing data and it can reduce the file size by up to 70%.

Gzip is based on the DEFLATE algorithm, which in turn is a combination of LZ77 and Huffman coding. Understanding how LZ77 works is essential to understand how compression methods like DEFLATE and Gzip work.

LZ77
Developed in the late ’70s by Abraham Lempel and Jacob Ziv, the LZ77 method of compression looks for sequences of characters that recur in a text. It performs compression by replacing the recurring occurrences of strings using pointers that backreference identical strings, previously encountered in the text, that needs to be compressed.

The pointer or backreference is of the form <relative jump, length>, where relative jump signifies how many bytes are there between the current occurrence of the string and its last occurrence and length is the total number of identical bytes found.

Now let us understand this better with the help of an example. Assume, there is a text file with the following text:

As idle as a painted ship, upon a painted ocean.

In this file, we see the following strings: “as” and “painted” occurring multiple times. What LZ77 method does is, it replaces multiple occurrences of strings with the notation: <relative jump, length>.

So using LZ77, the text will get encoded in the following way:

As idle <8,2> a painted ship, upon a <21,7> ocean.

To encode the text, we took the following steps:

  1. Looked at the string and tried to find occurrences of the same “string” or “substrings”.
  2. Replaced multiple occurrences of a string with the notation: <relative jump, length>; The two strings: “as” and “painted” were replaced the multiple occurrences of the strings with <relative jump, length>.
  3. The string “painted” which would have earlier occupied 7 bytes (i.e. the number of characters in the word: “painted”) X 1 byte = 7 bytes was compressed to occupy only 2 bytes. 2 bytes or 16 bits is the size of the pointer or backreference.

HUFFMAN Coding
Huffman Coding is another lossless data compression algorithm. The frequency of occurrence of a string in a text file or pixels in images form the basis of Huffman coding. To get a deeper understanding of this algorithm, read this detailed tutorial that clearly explains how Huffman Coding works.

All modern browsers support Gzip compression for HTTP Requests. With Gzip, one of the most important question is what to compress. It works best with text-based resources like static HTML, CSS files and JavaScript resources but is not very efficient for already compressed resources such as Images. To support Gzip, the server must be configured to allow gzip compression.

The image above shows the impact Gzip compression can have on a text-based resource like a JavaScript file. In this case, we ran 2 instant tests using Catchpoint to the URL: https://code.jquery.com/jquery-3.2.1.js.

For the first test run, we did not specify any encoding to be used by passing the custom header: Accept-Encoding: identity along with the request. The first image shows no Content-Encoding being passed for the request.

In the second image, the browser is sending Accept-Encoding:zip, for which the server is sending zipped file as the response.

We can clearly see how Gzip can drastically compress the files to improve data transmission rate over the wire.

Catchpoint’s Scheduled tests also highlight the difference between compressed and not-compressed content loading on webpages.

In the screenshot above, we see the difference in downloaded bytes for static content (CSS, JavaScript) when using G-zip vs. when not using any encoding.

Brotli Compression
A new compression method called Brotli was introduced not too long ago. The Brotli compression algorithm is optimized for the web and specifically for small text documents. We will discuss more about this compression method and what is has to offer to the World Wide Web community in the second part of the article.

The post Compression: Making the Big Smaller and Faster (Part 1) appeared first on Catchpoint's Blog - Web Performance Monitoring.

More Stories By Mehdi Daoudi

Catchpoint radically transforms the way businesses manage, monitor, and test the performance of online applications. Truly understand and improve user experience with clear visibility into complex, distributed online systems.

Founded in 2008 by four DoubleClick / Google executives with a passion for speed, reliability and overall better online experiences, Catchpoint has now become the most innovative provider of web performance testing and monitoring solutions. We are a team with expertise in designing, building, operating, scaling and monitoring highly transactional Internet services used by thousands of companies and impacting the experience of millions of users. Catchpoint is funded by top-tier venture capital firm, Battery Ventures, which has invested in category leaders such as Akamai, Omniture (Adobe Systems), Optimizely, Tealium, BazaarVoice, Marketo and many more.

@ThingsExpo Stories
Personalization has long been the holy grail of marketing. Simply stated, communicate the most relevant offer to the right person and you will increase sales. To achieve this, you must understand the individual. Consequently, digital marketers developed many ways to gather and leverage customer information to deliver targeted experiences. In his session at @ThingsExpo, Lou Casal, Founder and Principal Consultant at Practicala, discussed how the Internet of Things (IoT) has accelerated our abilit...
When shopping for a new data processing platform for IoT solutions, many development teams want to be able to test-drive options before making a choice. Yet when evaluating an IoT solution, it’s simply not feasible to do so at scale with physical devices. Building a sensor simulator is the next best choice; however, generating a realistic simulation at very high TPS with ease of configurability is a formidable challenge. When dealing with multiple application or transport protocols, you would be...
Data is the fuel that drives the machine learning algorithmic engines and ultimately provides the business value. In his session at Cloud Expo, Ed Featherston, a director and senior enterprise architect at Collaborative Consulting, discussed the key considerations around quality, volume, timeliness, and pedigree that must be dealt with in order to properly fuel that engine.
Detecting internal user threats in the Big Data eco-system is challenging and cumbersome. Many organizations monitor internal usage of the Big Data eco-system using a set of alerts. This is not a scalable process given the increase in the number of alerts with the accelerating growth in data volume and user base. Organizations are increasingly leveraging machine learning to monitor only those data elements that are sensitive and critical, autonomously establish monitoring policies, and to detect...
Dion Hinchcliffe is an internationally recognized digital expert, bestselling book author, frequent keynote speaker, analyst, futurist, and transformation expert based in Washington, DC. He is currently Chief Strategy Officer at the industry-leading digital strategy and online community solutions firm, 7Summits.
Two weeks ago (November 3-5), I attended the Cloud Expo Silicon Valley as a speaker, where I presented on the security and privacy due diligence requirements for cloud solutions. Cloud security is a topical issue for every CIO, CISO, and technology buyer. Decision-makers are always looking for insights on how to mitigate the security risks of implementing and using cloud solutions. Based on the presentation topics covered at the conference, as well as the general discussions heard between sessio...
In his session at @ThingsExpo, Arvind Radhakrishnen discussed how IoT offers new business models in banking and financial services organizations with the capability to revolutionize products, payments, channels, business processes and asset management built on strong architectural foundation. The following topics were covered: How IoT stands to impact various business parameters including customer experience, cost and risk management within BFS organizations.
Recently, REAN Cloud built a digital concierge for a North Carolina hospital that had observed that most patient call button questions were repetitive. In addition, the paper-based process used to measure patient health metrics was laborious, not in real-time and sometimes error-prone. In their session at 21st Cloud Expo, Sean Finnerty, Executive Director, Practice Lead, Health Care & Life Science at REAN Cloud, and Dr. S.P.T. Krishnan, Principal Architect at REAN Cloud, discussed how they built...
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, provided an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life settl...
IoT solutions exploit operational data generated by Internet-connected smart “things” for the purpose of gaining operational insight and producing “better outcomes” (for example, create new business models, eliminate unscheduled maintenance, etc.). The explosive proliferation of IoT solutions will result in an exponential growth in the volume of IoT data, precipitating significant Information Governance issues: who owns the IoT data, what are the rights/duties of IoT solutions adopters towards t...
With tough new regulations coming to Europe on data privacy in May 2018, Calligo will explain why in reality the effect is global and transforms how you consider critical data. EU GDPR fundamentally rewrites the rules for cloud, Big Data and IoT. In his session at 21st Cloud Expo, Adam Ryan, Vice President and General Manager EMEA at Calligo, examined the regulations and provided insight on how it affects technology, challenges the established rules and will usher in new levels of diligence arou...
Organizations planning enterprise data center consolidation and modernization projects are faced with a challenging, costly reality. Requirements to deploy modern, cloud-native applications simultaneously with traditional client/server applications are almost impossible to achieve with hardware-centric enterprise infrastructure. Compute and network infrastructure are fast moving down a software-defined path, but storage has been a laggard. Until now.
Digital Transformation is much more than a buzzword. The radical shift to digital mechanisms for almost every process is evident across all industries and verticals. This is often especially true in financial services, where the legacy environment is many times unable to keep up with the rapidly shifting demands of the consumer. The constant pressure to provide complete, omnichannel delivery of customer-facing solutions to meet both regulatory and customer demands is putting enormous pressure on...
DXWorldEXPO LLC announced today that All in Mobile, a mobile app development company from Poland, will exhibit at the 22nd International CloudEXPO | DXWorldEXPO. All In Mobile is a mobile app development company from Poland. Since 2014, they maintain passion for developing mobile applications for enterprises and startups worldwide.
The best way to leverage your CloudEXPO | DXWorldEXPO presence as a sponsor and exhibitor is to plan your news announcements around our events. The press covering CloudEXPO | DXWorldEXPO will have access to these releases and will amplify your news announcements. More than two dozen Cloud companies either set deals at our shows or have announced their mergers and acquisitions at CloudEXPO. Product announcements during our show provide your company with the most reach through our targeted audienc...
IoT is at the core or many Digital Transformation initiatives with the goal of re-inventing a company's business model. We all agree that collecting relevant IoT data will result in massive amounts of data needing to be stored. However, with the rapid development of IoT devices and ongoing business model transformation, we are not able to predict the volume and growth of IoT data. And with the lack of IoT history, traditional methods of IT and infrastructure planning based on the past do not app...
"Akvelon is a software development company and we also provide consultancy services to folks who are looking to scale or accelerate their engineering roadmaps," explained Jeremiah Mothersell, Marketing Manager at Akvelon, in this SYS-CON.tv interview at 21st Cloud Expo, held Oct 31 – Nov 2, 2017, at the Santa Clara Convention Center in Santa Clara, CA.
IoT is rapidly becoming mainstream as more and more investments are made into the platforms and technology. As this movement continues to expand and gain momentum it creates a massive wall of noise that can be difficult to sift through. Unfortunately, this inevitably makes IoT less approachable for people to get started with and can hamper efforts to integrate this key technology into your own portfolio. There are so many connected products already in place today with many hundreds more on the h...
More and more brands have jumped on the IoT bandwagon. We have an excess of wearables – activity trackers, smartwatches, smart glasses and sneakers, and more that track seemingly endless datapoints. However, most consumers have no idea what “IoT” means. Creating more wearables that track data shouldn't be the aim of brands; delivering meaningful, tangible relevance to their users should be. We're in a period in which the IoT pendulum is still swinging. Initially, it swung toward "smart for smart...
DXWorldEXPO LLC, the producer of the world's most influential technology conferences and trade shows has announced the 22nd International CloudEXPO | DXWorldEXPO "Early Bird Registration" is now open. Register for Full Conference "Gold Pass" ▸ Here (Expo Hall ▸ Here)