Only tunnel types built on PPP support authentication with username and password:
A.✔PPPoE – Built on PPP, uses CHAP, PAP authentication.
B.✔OpenVPN – Supports user/password login for client authentication.
C.✘IPIP – A stateless Layer 3 tunnel; no authentication support.
D.✔PPTP/L2TP – Both are PPP-based and support username/password authentication.
E.✘EoIP – MikroTik proprietary Layer 2 tunnel; no username/password authentication.
Extract from MTCNA Course Material – Tunnel Types:
“PPPoE, PPTP, and L2TP are PPP-based and support user/password authentication. IPIP and EoIP do not.”
Extract from René Meneses Study Guide – Tunnel Protocols:
“Authentication (PAP/CHAP) is part of PPP. Use PPPoE, PPTP, L2TP, or OpenVPN for user logins.”
Extract from MikroTik Wiki – Tunnel Protocols Overview:
“Only PPP-based tunnels support authentication via username/password.”
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