The Elastic IP Addresses allow Amazon Web Services users to set up static IP addresses, making it easy to host websites, web services and other online applications using Amazon EC2. Users can programmatically map the static IP addresses to any of their instances, making it easy to recover from instance failures.
By default, users are limited to a total of 5 Elastic IP Addresses, although additional IP addresses can be requested from Amazon. To ensure customers use the Elastic IP Addresses associated with their account, a $0.01 per hour charge is applied when each IP is not mapped to an instance.
The Availability Zones feature makes it easy and relatively inexpensive to operate a highly available internet application. Availability Zones are designed to be protected from failures in other Availability Zones, so by spreading an application across several zones, it can be better protected against power failures or network downtime.
This is not Amazon's first foray into web hosting - a number of high profile sites have been working with Amazon's Enterprise Solutions group for a few years, including Marks and Spencer, which signed a deal with Amazon in 2005. Amazon were to provide the technology behind the Marks and Spencer website as well as systems for customer service and ordering.
While the complexities of web hosting with Amazon's EC2 platform may appear rather daunting to the majority of web site owners, the service will no doubt appeal to existing owners of dedicated servers who want further scalability or wish to make their sites highly available at a reasonable cost.
Amazon's pricing for the EC2 service depends on a variety of factors. A single default "small" instance, with 1.7GB of memory and 160GB of storage, costs $0.10 per hour to run, with additional charges for data transfer and unused Elastic IP Addresses. An extra large instance costs $0.80 per hour and features 15GB of memory, 1690GB of storage and 4 virtual cores.
Internet data transfer costs depend upon the direction of the data. All data transfered in is charged at $0.10 per GB, while outwards transfers are $0.18 per GB for the first 10TB of data each month, reducing to $0.13 per GB if 50TB is exceeded.
With EC2's bandwidth costs significantly undercutting many hosting companies, Amazon's latest move will be sending shock waves throughout the conventional hosting industry. It will be interesting to see how the use of Elastic IP Addresses grows, as high bandwidth websites - or even entire hosting companies - are tempted to migrate to a cheaper alternative.