I would like to request, that if you're going to suggest: "Run instances in two or more Availability Zones." as a fault-tolerant architecture method (which everyone SHOULD do) - can we please have a flag or tag to say that "Traffic between Zone-1-HOST-A and Zone-2-HOST-A" is specifically resiliancy/HA/fault-tolerant connection traffic could benefit from a discount in zone transfer fees?

We are moving many hundreds servers between zones every day and sometimes by the hour, specifically to handle all sorts of constraints (Spot, capacity, failure, load, etc)...

I have paid quite a lot to zone transfer fees, especially when dealing with AWS network issues or spot price insanity.

I would love to classify some traffic as resiliency traffic and be charged differently for that traffic as opposed to general traffic used to service my user-base.

There already is a tiered pricing model for this.

Data that goes between AZ's is charged at $0.01 / GB.

Data that flows from an EC2 instance to the Internet is charged at $0.12 / GB (for up to 10 TB / month, with discounts from there, and there's also 1 GB / month of free traffic).

Details are on http://aws.amazon.com/ec2/pricing/

I know there is a tiered pricing, but I spend 5X on zone-to-zone data transfer over what data needs to leave AWS to my userbase. So, even with the tiered model, I still pay a lot just to get data around my app becuase I constantly have to swap boxes between zones.

As long as you are using the private IP or public DNS name outbound traffic between EC2 instances in different AZ's in the same region is $.01/GB, inbound is free.

Pricing is different for traffic going outside the EC2 network.