title: AWS Lambda Account Concurrency, Throttling
body: <p>I am considering NOT using API gateway for performance reasons. Instead, I want to expose a lambda function directly to the web. Unauthenticated IAM credentials are required, and provided by the AWS JavaScript SDK. I realize this could be a concern if a bad actor tries to invoke my function at an astronomical pace and cause major billing issues. I don't think this is likely as someone would specifically have to target my application, request IAM credentials and then invoke the request... a lot of work for little gain, but...</p>
  
  <p>In order to protect my Lambda Function from an attack I was considering the account concurrency feature. By default, the account concurrency feature is limited to 1,000 concurrent requests on the account. I am able to specify reserve concurrency specific to a Lambda function which reduces the remaining overall account concurrency limit (the concurrency limit for the rest of the account).</p>
  
  <p>Would this work: create a dummy lambda function (not publicly accessible), set the dummy Lambda function reserved concurrency really high, e.g. 950... this would leave 50 concurrent lambda requests for my "real" Lambda function... this seems like a simple way to throttle a lambda without using API gateway, etc.</p>
  
  <p>Thoughts?</p>