9. ◦ Uses a TCP connection for tunnel maintenance and generic routing encapsulated PPP frames for tunneled data. ◦ The payloads of the encapsulated PPP frames can be encrypted and/or compressed. L2TP – (Layer 2 Tunneling Protocol) ◦ Uses UDP and a series of L2TP messages for tunnel maintenance. PPTP – (Point-to-Point Tunneling Protocol )