The Bethesda Blog has word on how to get access to the DOOM multiplayer alpha test that's now being shown off in pre-alpha form to QuakeCon attendees. They explain they will select participants from the beta pools for Wolfenstein: The New Order for Windows, Xbox One, and PlayStation 4. Here's how this works:

Attendees at QuakeCon 2015 may be the first to go hands on with pre-alpha DOOM multiplayer, but we still have big plans for fans that pre-ordered Wolfenstein: The New Order.

In the coming months, we’ll be selecting Xbox One, PlayStation 4, and PC players from the Wolfenstein: TNO Beta pool to participate in the DOOM Multiplayer Alpha. To make sure you’re eligible, make sure you redeem your DOOM Beta code at www.wolfenstein.com/doom. If you purchased the game digitally through Steam, PSN, or Xbox Live, you’re already set — you have a digital entitlement that will ready you for the Alpha when it starts.

As a reminder, everyone that pre-ordered Wolfenstein: the New Order is eligible to participate in the multiplayer beta planned for next year before DOOM’s Spring 2016 release.