10 Best Site-To-Site VPN Protocols and When to Use Them


In today’s globalized digital landscape, it’s more important than ever for organizations to safeguard data as it moves between different locations. Site-to-site VPNs offer secure interconnectivity, enabling geographically dispersed offices, data centers, and remote sites to communicate over public networks while shielding sensitive information from cybercriminals. 

Behind the scenes, VPN protocols empower secure, seamless, and confidential exchange between these network endpoints.

What is a Site-to-Site Virtual Private Network (VPN)? 

A business VPN can keep employees and remote workers connected to corporate offices, enabling them to share resources and collaborate with team members no matter where they are located.

Specifically, a site-to-site VPN offers a permanent, secure, always-on connection between two or more geographically separate local area networks (LANs) in an organization. A site-to-site VPN essentially creates a corporate intranet, allowing data exchange between sites in different locations while keeping unauthorized users out. 

The Difference Between Site-To-Site VPN and Remote Access VPN

A site-to-site VPN, or router-to-router VPN, creates an encrypted virtual tunnel to protect data as it travels over a public or untrusted network like the internet from one LAN to another. For example, they can connect branch offices to a central corporate network or link multiple data centers.

Site-to-site VPNs often require dedicated hardware, such as routers and firewalls, at each network location to handle the VPN connections and are usually configured and managed by an enterprise IT department. 

In contrast, remote access VPNs are designed to connect individual devices, such as laptops and smartphones, to corporate networks from remote, out-of-office locations. Remote access VPNs require software installed on each user’s device, which communicates with a VPN server on the organization’s network.

When a user requires access to corporate resources, they enable a VPN connection, verify their credentials, and disconnect at the end of each session.

What Is a VPN Protocol?

VPNs create an encrypted pathway, or a tunnel, for data to pass securely between the internet and the corporate network. A VPN protocol is a set of rules used to encrypt, send, and authenticate data safely through the tunnel, keeping confidential and protecting it from unauthorized interception or manipulation.

Most Common VPN Protocols

The selection of tunneling protocols for corporate VPNs depends on various factors, including security requirements, compatibility with the network infrastructure, and the specific use case. 

Here’s an at-a-glance summary of commonly used VPN protocols:

ProtocolDescriptionEncryptionSecurityBest Use Cases
PPTP (Point-to-Point Tunneling Protocol)The earliest VPN protocol, high compatibilityWeak encryption (MPPE)Considered less secure due to vulnerabilitiesLegacy systems, basic security needs
L2TP (Layer 2 Tunneling Protocol)Creates a protective tunnel, often used with IPsec for greater safetyNo encryption (used with IPsec)Enhanced security when used with IPsecRemote access, site-to-site connections
IPsec (Internet Protocol Security)Uses strong locks and keys to limit access to authorized usersStrong encryption and authenticationHigh security, widely adoptedSecure remote access, site-to-site VPNs
SSTP (Secure Socket Tunneling Protocol)Uses a secure layer, like a shield, to protect data as it travelsOpen source creates a customizable tunnel to connect to the networkSecure, integrated with WindowsWindows-centric environments
OpenVPNCreates an efficient VPN for large networks, uses labels to securely route data to different areas, and keep it privateHighly configurable, strong encryption, uses TCP and UDP security protocolsHigh security, flexibilityVersatile, secure VPN for various needs
IKEv2/IPsec (Internet Key Exchange v2)Ensures a fast, stable, safe connection, even when travelingStrong encryption, fast reconnectionHigh security, reliableMobile devices, seamless roaming
WireGuardOpen source, creates a fast, secure highway for dataHigh-speed encryptionSimplicity, performance, high securityHigh-performance VPNs, security-focused
SSH (Secure Shell)Provides a secure connection for remote access to serversStrong encryptionSecure remote access and data transferSecure remote server management
MPLS (Multiprotocol Label Switching) VPNCreates an efficient VPN for large networks, uses labels to securely route data to different areas, and keeps it privateVarious, including layer 2 and layer 3High security, efficient routingLarge-scale enterprise networks
Hybrid VPNHighly versatile, combines various VPN types and protocols to meet organizational needsCombination of various protocolsCustomizable security and performanceTailored to specific needs

Let’s go into each one.

Internet Protocol Security (IPSec)

IPsec is like a high-security vault for your data. It uses strong locks and keys to make sure your corporate network is only accessed by authorized employees. It’s one of the safest choices.

Internet Key Exchange Version 2 (IKEv2)

IKEv2/IPsec is a protocol that’s really good at keeping your connection strong and secure. It’s especially handy for mobile devices and ensures your connection stays secure even if you move around a lot.

Layer 2 Tunneling Protocol (L2TP)

L2TP is like a protective tunnel for your data. It’s often used with another security method called IPsec to make sure your information stays safe while traveling between your computer and the corporate network.

Point–to–Point Tunneling Protocol (PPTP)

PPTP is an older and simpler way to create a secure connection between your computer and a corporate network. It provides some security, but it’s not considered the most secure option.


OpenVPN is like a super customizable and secure tunnel for your data. It can work with various types of devices and provides top-notch security. Think of it as a Swiss Army knife for VPNs.

Secure Socket Tunneling Protocol (SSTP)

Developed by Microsoft, this protocol creates secure, encrypted connections between a client (usually a Windows computer) and a VPN server. SSTP incorporates SSL/TLS security protocols for encryption to provide secure data transmission between web browsers and web servers. SSTP is often used to provide secure remote access to corporate networks.


WireGuard is like a super-fast and secure highway for your data. It’s known for its simplicity and speed, making it a great choice for high-performance VPNs where speed and security are both important.

Secure Shell (SSH)

SSH creates secure tunnels to protect computer-to-computer access. It’s often used to provide remote access and manage servers or devices over an unsecured network like the Internet. SSH is involved in data encryption and credential authentication methods to ensure security.

Multiprotocol Label Switching (MPLS) VPN

MPLS acts like a postal system, routing data efficiently through large networks. It uses labels (like zip codes) to quickly and securely route data between different parts of a network. It’s commonly used by big organizations to connect their offices and data centers while keeping their data private and organized. 

Hybrid VPN

Hybrid VPNs combine different types of VPNs and network technologies to create a custom solution that fits your specific needs. It’s like choosing the right tools for different jobs, ensuring you have the right balance of security and performance for your network.

How to Choose the Right VPN Protocol For Your Business

VPN protocols play pivotal roles in safeguarding your data and ensuring secure communication over the internet or private networks. Since VPN protocols can significantly impact the security, performance, and versatility of your connection, it’s important to choose the right ones to meet your organization’s needs.

Confused by Site-to-Site VPN protocols and how they can help you meet your company’s security goals? For more detailed information, book a demo and get a 20-minute consultation from our knowledgeable team today.


Which is the most secure VPN protocol?
The most secure VPN protocol can vary depending on specific use cases and security requirements. However, OpenVPN and IPsec are often considered among the most secure.

OpenVPN is highly respected in its field for strong security features like AES encryption algorithms and robust authentication methods. Since it is highly customizable, enterprises can easily implement security best practices according to their individual needs. Its open-source nature allows for ongoing scrutiny and development by the security community.

IPsec also provides strong encryption and authentication for securing both site-to-site and remote access VPNs. IPsec can operate in both Transport mode (for securing individual packets) and Tunnel mode (for securing entire communications channels). When combined with IKE (Internet Key Exchange) protocols, IPsec can establish secure connections efficiently.

The choice between OpenVPN and IPsec often depends on factors like platform compatibility, network infrastructure, and specific security needs. It’s essential to configure and manage these protocols properly to maximize their security. 
Which VPN protocol is the fastest?
Speed can vary depending on network conditions, server load, and other factors, but a few VPN protocols stand out in this area:

– With less than 4,000 lines of code, WireGuard was intentionally crafted with a minimalist approach, prioritizing high performance and efficiency.
– Together, IKEv2 and IPsec provide fast connection establishment/reconnection capabilities, especially in mobile environments where users move between Wi-Fi and data connections.
Which protocol does site-to-site VPN use?
Organizations need to select protocols that meet their security requirements, work with their network infrastructure and budgetary constraints, and other needs specific to their business. That said, some protocols are more suitable for site-to-site VPN environments than others. 

IPSec is often combined with other protocols for use in site-to-site VPNs because of its strong encryption and authentication mechanisms and because it is highly compatible with a variety of devices, operating systems, and network configurations. 

OpenVPNs strong security features and efficiency make it a popular choice for site-to-site VPNs, though compatibility can be an issue on router-to-router networks.

WireGuard is newer, but it is growing in popularity for use with site-to-site VPN setups because of its performance and security features. Some organizations opt for MPLS-based site-to-site VPNs. Though costly, MPLS is considered effective for large-scale deployment when high performance over multiple locations is needed.
Does site-to-site VPN use IPSec?
Site-to-site VPNs commonly use the Internet Protocol Security protocol to establish secure connections between different physical locations or networks. IPsec is a widely adopted and trusted protocol for creating encrypted and authenticated VPN connections, making it a popular choice for securing data transmission between sites in a site-to-site VPN configuration.

IPsec provides strong encryption and authentication methods, ensuring data transmitted over the VPN tunnel remains confidential. It can operate in either Tunnel mode or Transport mode, with Tunnel mode being more common for site-to-site VPNs. In Tunnel mode, the entire IP packet is encapsulated and encrypted, allowing for secure communication between the connected networks.

IPsec is well-suited for site-to-site VPNs because it can handle the secure interconnection of different physical locations or networks, making it a preferred choice for organizations that need to establish secure connections between their branch offices, data centers, or remote sites.
What are the two types of site-to-site VPN?
Site-to-site VPNs come in two different types, depending on the needs of your business:

– Intranet-based site-to-site VPNs connect multiple remote locations within the same organization, such as branch offices or data centers, to a central corporate network. 

– Extranet-based site-to-site VPNs are used to facilitate secure collaboration between separate organizations. They allow organizations to share specific resources with outside entities without compromising network security. These connections are critical for industries with strict compliance requirements, like healthcare or finance, that rely on secure data sharing.
What are the two most commonly used VPN protocols?
Many organizations opt for protocols like IPsec or OpenVPN due to their robust security features and widespread support.  

IPsec is a set of protocols used to secure internet communication, including VPNs. It operates at the network layer of the OSI model and provides strong security features. IPsec is known for its efficiency in handling VPN connections, making it suitable for high-performance scenarios and large-scale deployments.

OpenVPN provides strong encryption and authentication methods. It is known for being highly secure and very versatile. It is not tied to a specific operating system or platform, making it widely compatible and customizable. Since OpenVPN is open-source, a strong community of developers and users ensures its ongoing development and security.
What is the difference between VPN protocols?
In general, the difference between VPN protocols lies in how they establish secure connections, encrypt data, authenticate users or devices, and handle various aspects of network communication. Key differentiating factors include:

– Security strength of encryption, authentication, and other features
– Compatibility with specific devices, operating systems, or network configuration
– Impact on network performance
– Ease of configuration
– Overall reliability
– Use cases