Using LDAP to authenticate Telnet client

We currently have a software vendor that requires telnet to be opened for GPS mapping on their hosted customer facing application. With this in mind, is there a way to enable LDAP to authenticate a Telnet session.

Currently, only those login IDs internal to the modem can be authenticated. Using LDAP is a easy method to manage access to modems currently deployed (around 900 devices).

Which module are you talking about?