Catchpoint Domain Override

Catchpoint Domain Override

In my previous blog A/B testing on CDN improvement we shared how to use A/B test to demonstrate the webpage performance brought by CDN. No matter what tool we used, it required customers to change their webpages to insert some JavaScript codes.

What if our goal is to minimize customer changes during the demonstration/proof of concept stage? I am going to demonstrate Catchpoint performance measurement service to achieve this goal.

Well, let’s take one step further to avoid ANY customer changes!

Catchpoint is one of the popular performance monitoring services. Many enterprises and cloud service providers buy Catchpoint solutions to monitor their websites and Internet services.

One cool Catchpoint feature is domain sharding/override. When it does page load test, Catchpoint can be configured to change the hostnames, say from A to B, in the HTML codes. By doing so Catchpoint will GET the HTTP objects from host B instead of A.

Let’s use this original webpage as an example. 82% of the page size comes from four images. I am going to do an A/B test on it. Original webpage is Test A. In Test B the four images will be delivered from EdgeCast CDN rather than the customer origin server in Singapore. This simulates actual CDN deployment on this webpage.

Step 1: I set up EdgeCast CDN services to cache the four images from the customer origin.

Step 2: I set up Catchpoint to test the original webpage from several Asia countries. This is Test A.

Step 3: I configure another test to test the original webpage again and use the domain override feature to change the original hostname (of the host of the four images) to the EdgeCast CNAME I set up in Step 1. This is Test B.

Step 4: This step is not a must-have and I use it for Control only. I add a new webpage in the customer origin. The new webpage is the same as the original webpage but in the HTML code I change the hostname of the four images to the EdgeCast CNAME I set up in Step 1. This is Test C.

I run the tests for 24 hours. Online reports: Test A vs B, Test A vs B vs C.

Below screen capture shows the page load time, response time and availability test results of Test A and B in the last two days. It shows Test B performed much better than Test A, Average Webpage Responses are 3962ms vs 5131ms, a 23% reduction. We did the test WITHOUT any customer changes!

Test A vs B

Test A vs B

You may wonder if Test B is a good simulation. Below screen capture shows the test results of all Test A, B and C. Test B and C results are similar (Average Webpage Responses are 3959ms & 4089ms respectively). I find the Catchpoint domain override feature is a good simulation of CDN deployment.

Test A vs B vs C

Test A vs B vs C

Google search “CDN Hong Kong”

CDN Hong Kong

Last week I chatted with different friends in different occasions about how to reach potential customers online more effectively. One critical question is what potential customers will do when they are looking for something?


Most of the time Google. Sometimes Yahoo or Bing. Right?

So, the question becomes “can your potential customers find your information when they Google search?”

SEO Made Simple is a great book about Search Engine Optimization written by Michael H. Fleischner.

“The ideas, steps and strategies shared in this book is easy to understand and beginners in SEO can easily apply them to their websites.”

Below are some of the key optimizations:
– include your keyword phases in the meta tag
– proper meta tags include title tag, description tag, keywords tag and robots tag
– chose your URLs carefully
– design your webpages to force Google to read on-page content first
– include keyword phases in header tags
– italicize, bold and underline your keyword phase within content
– keyword development
– have a large number of quality sites linking to your webpages

How easy? Very easy! I use both SEO ideas mentioned in the book and EdgeCast CDN services in my blog and my CDN demo site.

In my blog More visitors and higher conversion rates? SEO + FEO, I shared how important is page load time to websites and how FEO and CDN would improve page load time. What every marketer needs to know about page speed’s effect on pagerank is another great article about speed and Google search rankings.

Does it work? As of 16-Apr-2013, I am quite happy with the Google search results pointing to my blog and demo site, my blog or demo site are usually listed in first result page:

search terms
CDN demo 1 3
CDN demonstration 1 1
how to use EdgeCast 1 1
EdgeCast CDN 12 7
what is CDN EdgeCast 2 2
CDN video iPhone 2 2
CDN video access control 1 1
CDN control rules 1 1
accelerate small objects 1 1
flash video CDN 2 3
CDN A/B test 1 1
EdgeCast Edge Optimizer 1 1
EdgeCast Application Delivery Network (ADN) 1 1
mobile optimized Webpage EdgeCast 1 1
CDN Hong Kong 18
(1, update: 20130509)
(1, update: 20130509)
“CDN Hong Kong” 1 1
Synthetic Performance Measurement
(add: 20130501)
(update: 20130509)
(update: 20130509)
CDN Hotlinking Prevention
(add: 20130501)
(update: 20130509)
(update: 20130509)
EdgeCast live video streaming
(add: 20130509)
(update: 20130509)
(update: 20130509)

I am using the same techniques in this article too. Let’s see later what are the Google search rankings when people Google search “CDN Hong Kong“.

EdgeCast Application Delivery Network (ADN) improves dynamic content performance

EdgeCast Application Delivery Network

EdgeCast Application Delivery Network (ADN) improves web page performance by optimizing TCP/IP network paths & communications to reduce latency and increase speed of non-cacheable content.

Dynamic content cannot be practically/effectively cached because a dynamic asset previously generated by a web application would never be requested again. ADN finds other ways through which to speed up data delivery to clients. ADN is able to drastically reduce the amount of time that it takes to communicate with the origin server by optimizing the network path and through the use of both server efficiency and RFC-compliant protocol optimizations. This allows these dedicated servers to transmit dynamic data at a much faster rate than traditional Internet data routes.


EdgeCast ADN performs better than traditional Internet because
EdgeCast PoPs around the world are connected with each other with best selected routes at multi-hundred Gbps capacities
– TCP/IP connections between EdgeCast edge servers and ADN gateway servers are optimized by techniques such as TCP Fast Start, TCP Packet Sizing, Congestion Avoidance, Connection and Packet Multiplexing, etc.
– The closet EdgeCast ADN gateways will be selected to connect to customer origin to maximize transmission performance between customer origin and EdgeCast ADN
– The closet EdgeCast ADN edge servers, based on BGP Anycast technology, will be selected and connected to client to maximize transmission performance between client and EdgeCast ADN

Therefore by routing traffic through EdgeCast ADN rather than public Internet, customer origin can send dynamic content to client at higher speed!

To demonstrate EdgeCast ADN, I simulate dynamic content by adding the following codes in the .htaccess fileĀ under the directory
<FilesMatch “.(jpg|jpeg|png|html)$”>
Header set Cache-Control “max-age=0, private, no-cache, no-store”

The original page is
The ADN optimized page is

Random tests at Webpagetest show the ADN optimized page loads faster than the original page:
Webpagetest result of the original page
Webpagetest result of the ADN optimized page
Webpagetest visual comparison

Webpagetest Visual Comparison

We can see the Time to First Byte and Content Download of those objects delivered from EdgeCast ADN – the HTML code and the image edgecast-adn.jpg – are faster than that of the origin page.

Google Analytics Page Timings on 4-Apr-2013:
– Original page: 2.25sec average page load time
– ADN optimized page: 1.79sec average page load time

Please click the original page and ADN optimized page to see & feel the performance improvement yourself! Your engagement will help generating more RUM data too!