This object reports which underlying remote-access protocol, such as IPsec, PPTP, L2TP, or SSL VPN, this specific session is actually using to establish its tunnel. It matters because different protocols have different security postures, performance characteristics, and troubleshooting procedures, so knowing which one a given session uses determines which set of diagnostic tools and logs an admin should consult when that session has a problem. An admin seeing a session unexpectedly using a legacy protocol like PPTP, known to have serious cryptographic weaknesses, in an organization that believes it has phased that protocol out entirely would treat that as an urgent finding.