Relative domain name for roles

[Web Developer]

I'm using the <authorization> node in the web.config of my web services to
permit access to specific roles. However, the roles are defined on each
server in the web farm instead of on the domain (by design). Is there a way
to refer to the domain of a role in a relative way like "localhost" so I can
deploy the same .config to each server without having to change the domain
specifics of the "Role" element?

For example:

<authorization>
<allow roles="localhost\AllAccess" />
</authorization>

Unfortunately, omitting the domain name doesn't resolve to the local machine.

Thank you.