The recent announcement of the Terremark Cloud offering has raised significant attention especially because of the competitive pricing and EC2 like features of elastic capacity and hourly charges with no commitment. On the surface the Terremark entry price of $0.036 per hour seems very low compared to Amazon EC2 at $0.10 but it's worth picking a few examples to provide a more apples to apples comparison.

Not included in the comparison is the difference in storage costs which can be small or very significant depending on the circumstance. Amazon provides up to 160 GB of instance storage for a small image or 850 GB for a large included in the hourly cost. If you have only a small instance say 10GB that adds $ 2.50 to the monthly price at Terremark ( @ .25/GB ) however of you needed the 850 GB included in the Amazon Large image that would add $ 212 to the monthly Terremark costs. Also not included is bandwidth costs, however both charge the same $0.17 GB for data transfer out . ( Although Amazon charges $ 0.10/GB for data in vs Terremark $ 0.17 data in ).

Some the bigger differences will more likely depend on how the VMs are utilized. The numbers stated above assume a full month of 24x31 operation. With Amazon EC2 it's possible to save in S3 ( bundle in Amazon terms ) an instance and then shut down ( terminate ) the VM and the billing stops. With Terremark however although you can shut down the VM, the hourly charges do not stop. Only deleting the VM ends the billing, there does not appear to be an option of saving with the hourly charges turned off and allowing a new instance from the saved image to be started at a later time. This appears to be a big advantage for Amazon although I need to learn more about the Terremark offering to fully appreciate the capabilities.

Certainly economics is not the only factor in selecting a Cloud infrastructure provider. Vendor Lock-in and VM portablity often come up as concerns. Security is also a factor in regard to Cloud computing and this was a motivator for Amazons recent Virtual Private Cloud offering which provides a dedicated VPN connection from a customer premise to an isolated Cloud inside the Amazon infrastructure. I also have to admit I was impressed with a recent tour of the Terremark data center in Miami , this place was like a high tech Fort Knox when it came to security. The entire topic of Cloud security is worthy of specialized consideration not covered in this simple comparison. Ease of use is another consideration that is worth evaluating. The Amazon Web Console is limited in function but easy to use plus includes access to many partner and community provided ( including Citrix C3 Lab ) templates that are prebuilt and ready to launch. In Amazon EC2 for example its now possible signup and launch your own XenApp server in as little a 15 minutes.

Terremark also provides a web base console that looks straight forward however I have not used it myself yet. Terramark does not provide the same portfolio of 3rd party templates however they do provide more granularity in the size of VMs and RAM plus they offer multiple versions of Windows Server. As the options for Cloud Computing continue to expand the economic analysis of Cloud vs Premise will extend to Cloud vs Cloud, as Service Providers continue to provide dynamic cloud type offerings.

Cloud Economics Part 1 - Premise vs Cloud vs Colo

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