AWS Elemental MediaLive
User Guide

Purpose of an Input Security Group

An input security group restricts access to an input and prevents unauthorized third parties from pushing content into a channel that is associated with a "push" input. Input security groups are required with RTP and RTMP “push” inputs; they do not apply to "pull" inputs such as HLS. Without the protection of this feature, any third party could push content to an MediaLive input if they know the IP address and port. Note that setting permissions on the account that owns the channel does not prevent this third-party push; only an input security group prevents it.

You can attach an input security group to more than one input; one input security group can "serve" several inputs.