Content Delivery Network (CDN)


CDN improves the delivery of content by replicating commonly requested static files across a globally distributed set of caching servers, which optimizes the deliver of static content to browsers by caching content in locations as close as possible to the User.

Overview

CDN improves the experience of the requestor by delivering a local copy of the content from a nearby cache edge, or Point of Presence (POP). When a viewer requests the content, the best edge location is determined to serve the content. If an edge location doesn’t have a copy of the file requested by the viewer, a copy is pulled from the Learndot server and is held at the edge location so it’s available for future requests. However, there is more to CDN than just caching. CDN also helps to deliver dynamic content that is unique to the requestor and not cacheable.

App Aim

It is important first to understand the goal of CDN and what problem it will solve. The purpose of this is to:

  • No longer deliver all content through your Learndot Instance and instead use the CDN Point of Presence (POPs). This will relieve Learndot Servers from this load. 
  • Improve the user experience by delivering content through a specialized infrastructure. Which can help to alleviate bottlenecks, increase availability of content and deliver it much faster. 

CDN Benefits

It is great to have detailed learning materials however, sometimes they can cause heavy loads on the Servers and at the same time, slow down responses to various viewers. With CDN, your content will always be on high availability and be able to serve multiple viewers at the same time. For example the chart below showcases the difference between the responses made by the CDN Edge Locations vs when the data had to be fetched from the Origin,

  • The Green line indicates the total number of bytes that was served to viewers from CDN Edge Locations in response to all requests. 
  • The Blue line indicates the number of bytes that was served to viewers for objects which were not present in the CDN Edge locations cache at the time of the request. This linear representation is a good approximation of bytes that were transferred from your Origin to the CDN Edge caches. 

Content Delivery via CDN

Learndot utilizes CDN to deliver content in two main categories, which are:

  1. Public Content
  2. Private Content

Public Content

This type of content is usually shared across all Learndot Customers. Examples include CSS, Javascript, Libraries and Images. 

Example

Most of your static public content (accessible to all) like Images, HTML/CSS, Javascript is cached in Edge Locations (servers) across the globe (as indicated below) to ensure that there is high availability and fast response time. This will ensure that the Learners receive optimal performance regardless of their locations.

Private Content

This type of content is usually specific to a Learner. An example would be a SCORM package from an eLearning Component, that content would belong to a Learner that signed a cookie with an auto-generated Universally Unique Identifier (UUID). Therefore, only the Learners with the right signatures have access to that specific content.  

Example

If you are hosting plenty of bulky Digital resources like SCORM content, Audio and Videos, and also have Learners that are spread out globally but you are hosting everything from one place (example, US). Considering the distance of some Learners, this would be slow and not scalable. With CDN, your content is cached in Edge Locations (Servers) across the globe, as shown below. This will ensure Learners do not have to wait longer to consume the resources.


CDN Locations

To deliver content to end users with lower latency and high availability, Learndot utilizes a global network of edge locations (in US, South America, Canada, Europe, Asia, Australia) for content delivery.

US OnlyEuropeAsiaAustraliaSouth AmericaCanada
Ashburn, VAAmsterdam, The NetherlandsChennai, IndiaMelbourneSão Paulo, BrazilMontreal, QC
Atlanta, GA Berlin, Germany

Hong Kong, China

SydneyRio de Janeiro, BrazilToronto, ON

Chicago, IL

Dublin, IrelandMumbai, India


Dallas/Fort Worth, TXFrankfurt, GermanyNew Delhi, India


Hayward, CA

London, EnglandOsaka, Japan


Jacksonville, FL

Madrid, SpainSeoul, Korea


Los Angeles, CAMarseille, FranceSingapore


Miami, FL

Milan, ItalyTaipei, Taiwan


Minneapolis, MN

Munich, GermanyTokyo, Japan


New York, NYParis, FranceManila, Philippines


Newark, NJ

Prague, Czech Republic



Palo Alto, CA

Stockholm, Sweden



Philadelphia, PA

Vienna, Austria



San Jose, CA

Warsaw, Poland



Seattle, WAZurich, Switzerland



South Bend, IN






St. Louis, MO






CDN Packages

Learndot offers two varieties of CDN packages, Premier and Standard package. Select any of the below two packages depending on your content caching needs. Contact the Learndot Support Team to find out more. 

Premier Package

The Premier package offered by Learndot includes all Edge locations (in US, South America, Canada, Europe, Asia, Australia), granting the quickest and highest availability of content and its delivery to the viewers. 

Standard Package

The Standard package offered by Learndot only includes three (3) continental Edge locations (in US, Canada and Europe) only. This is useful if your viewers are not worldwide and only in chosen locations.