Is SSTP or L2TP/IPsec Better for Bypassing Firewalls?

1. What is SSTP (Secure Socket Tunneling Protocol) and how does it work for bypassing firewalls?
2. How does L2TP/IPsec (Layer 2 Tunneling Protocol with Internet Protocol Security) function and what are its key features?
3. In terms of bypassing firewalls, how does SSTP compare to L2TP/IPsec?
4. What are the advantages of using SSTP in terms of firewall bypass effectiveness?
5. What makes L2TP/IPsec a versatile choice for VPN protocols across different platforms?

In the evolving landscape of internet security and firewall technology, understanding the effectiveness of various VPN protocols is crucial. This article delves into the specifics of SSTP (Secure Socket Tunneling Protocol) and L2TP/IPsec (Layer 2 Tunneling Protocol with Internet Protocol Security), comparing their abilities to bypass firewalls.

Understanding SSTP (Secure Socket Tunneling Protocol)

How SSTP Works

SSTP, primarily used in Windows environments, leverages SSL/TLS encryption, similar to that used in secure web traffic (HTTPS). This encryption is robust and provides secure communication channels.

Key Features

• Encryption: Utilizes SSL/TLS, offering strong security.
• Port Usage: Operates on TCP port 443, commonly used for HTTPS traffic.
• Platform Support: Best support on Windows; limited on other platforms.

SSTP and Firewalls

SSTP’s primary advantage in bypassing firewalls lies in its use of TCP port 443. Since this port is also used for secure web traffic, SSTP’s traffic is hard to differentiate from regular HTTPS traffic, making it less likely to be blocked.

SSTP Traffic Analysis

Aspect	Detail
Encryption Type	SSL/TLS
Port Used	TCP 443
Traffic Indistinguishability	High
Firewall Bypass Effectiveness	High

Examining L2TP/IPsec

How L2TP/IPsec Works

L2TP/IPsec is a combination of the L2TP tunneling protocol and IPsec encryption. This protocol is widely supported across different platforms, making it a versatile choice.

Key Features

• Encryption: Uses IPsec, providing strong security.
• Port Usage: Utilizes UDP ports 500 and 4500.
• Platform Support: Broad support across Windows, macOS, iOS, and Android.

L2TP/IPsec and Firewalls

L2TP/IPsec traffic is more identifiable than SSTP due to its use of specific ports and protocols. Firewalls with deep packet inspection capabilities can potentially block L2TP/IPsec more easily.

L2TP/IPsec Traffic Analysis

Aspect	Detail
Encryption Type	IPsec
Port Used	UDP 500, UDP 4500
Traffic Indistinguishability	Moderate
Firewall Bypass Effectiveness	Moderate

Comparing SSTP and L2TP/IPsec

When evaluating SSTP and L2TP/IPsec for bypassing firewalls, several factors come into play:

Traffic Indistinguishability

• SSTP: High indistinguishability due to common port and encryption type with HTTPS.
• L2TP/IPsec: Moderate indistinguishability due to fixed port usage and recognizable IPsec protocol.

Firewall Bypass Capability

• SSTP: Generally more effective in bypassing firewalls due to traffic blending with regular HTTPS.
• L2TP/IPsec: Less effective in environments where deep packet inspection is used.

Platform Support and Usability

• SSTP: Best on Windows, limited on other platforms.
• L2TP/IPsec: Broadly supported and easy to set up on various devices.

Conclusion: Choosing the Right Protocol

In summary, SSTP, with its SSL/TLS encryption and use of TCP port 443, is often more effective in bypassing firewalls, particularly in environments where firewall settings are stringent. L2TP/IPsec, while slightly less effective in this regard due to its identifiable characteristics, remains a strong contender for its widespread platform support and robust security.

When selecting a VPN protocol for bypassing firewalls, consider the specific network environment, firewall configurations, and platform compatibility. Both SSTP and L2TP/IPsec have their unique advantages, and the best choice may vary depending on individual needs and constraints.

02.02.24

Written by: Carl J. Jones