Improved methods, apparatus, and systems for obtaining information regarding a formation, a casing, or fluid within the casing utilize an interrogator and one or more sensing devices attached to a casing in a wellbore. Such a system may include a plurality of implantable neuromodulation units that communicate with one another over a network. Text messages are exchanged between users using specific profiles. A second stage of the two-stage process involves, based on receiving a notification that a PE router is VPLS enabled, generating a query message to discover a set of VPLS instances to which the broadcasting PE router belongs.