Which of the following ports must be opened on the firewall for the VPN connection using Point-to- Point Tunneling Protocol (PPTP)?

The correct answer is D. TCP port 1723. TCP port 1723 is the standardized port for PPTP (Point-to-Point Tunneling Protocol), defined in RFC 2637, and must be open on the firewall alongside GRE protocol 47 to allow PPTP VPN tunnels to establish. Port 110 is POP3 (email retrieval), port 443 is HTTPS (secure web traffic),

Infrastructure Security

Question

Options

ATCP port 110
BTCP port 443
CTCP port 5060
DTCP port 1723

How the community answered

(33 responses)

B
6% (2)
C
3% (1)
D
91% (30)

Explanation

TCP port 1723 is the standardized port for PPTP (Point-to-Point Tunneling Protocol), defined in RFC 2637, and must be open on the firewall alongside GRE protocol 47 to allow PPTP VPN tunnels to establish. Port 110 is POP3 (email retrieval), port 443 is HTTPS (secure web traffic), and port 5060 is SIP (VoIP signaling) - none of these have any relation to VPN tunneling protocols. A useful memory trick: 1723 = "17-23" - think of it as a "tunnel" number, or associate PPTP's "P" (the 16th letter) + 1 = 17, giving you the start of 1723.

Topics

#PPTP#VPN protocols#Firewall configuration#Port 1723

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