PPTP: when a PC is connected to the internet a control connection (tunnel) to the server using TCP is established working with PPP
Characteristics of PPTP
1) It’s a layer 2 protocol which encaplsulates PPP frames in IP datagram’s for transmission over an unsecured public IP network such as the internet (Vilates OSI standards)
2) It accomplishes authentication like PPP (PaP, Chap, MSchap)
3) It requires an IP based network. Header compression is not supported. PPTP doesn’t support IPsec and encryption is provided using standard PPP methods.
The Data sent are encapsulated by IP data can be
• TCP port 1723
• Another Datagram
• An IPX message
• A Net BEUI message