Apache: allow local connections to bypass basic authentication
You can tell apache to allow connections from specific IP addresses, like this:
Allow from 192.168.0.1/24
Satisfy Any
If you add that to your authentication scheme it will allow any IP address in the 192.168.0.1 - 192.168.0.254 range to access your content.
A full example may look like this (I am using digest, just substitute with your basic code):
<Location />
Order deny,allow
Deny from all
AuthName "SomeSite"
AuthType Digest
AuthDigestProvider file
AuthDigestDomain http://somesite.com
AuthUserFile /etc/apache2/password.file
Require valid-user
Allow from 192.168.0.1/24
Satisfy Any
</Location>