A short introduction to content delivery networks: why they exist, the types of CDNs and how they can help us.

1. CDNs

2. Does speed really matter?

3. Problems that a CDN can solve
● Bandwidth issues
● Slow page load times for users far from the
servers
● High load on some servers and low on others
(load balancing)
● Availability issues – the webapp is down
because the server is offline

4. Areas that a CDN can improve
● Network latency
● Packet loss
● Server capacity
● Server load
● Cache

5. Types of CDNs
● Peer to peer CDN (peer5)
● Public CDN Amazon CloudFront, Google
Fonts, Microsoft Azure
● Private CDNs

7. Peer to peer sounds familiar

8. Time to first byte

9. With CDN

10. CDN performance improvement

12. What a CDN can't fix
● Server-side processing.
● Third-party scripts that block the rest of the page
from rendering.
● Badly optimized pages, in which non-essential
content renders before primary content.
● Unoptimized images (e.g. images that are
uncompressed, unconsolidated, non-progressive,
and/or in the wrong format).
● Unminified code

13. Citations
● bittorrent.org/beps/bep_0005.html
● sciencedirect.com/science/article/pii/S108480
4509000551
● webperformancetoday.com/2014/04/22/new-
findings-retail-sites-use-cdn-slower-sites/