Site-to-Site VPN: What is a Site to Site VPN, and does my business need one?

VPNs designed to serve individual users are not powerful enough to cater to the needs of medium to large-scale organizations. In several cases, large enterprises send vast volumes of data between locations. A typical VPN may not be able to transfer all this data with the desired performance securely – this is where site-to-site VPN can prove to be helpful.

The ability of private VPNs to provide a more secure, encrypted connection free of the risk of cyberattacks makes it a popular choice among users. A Site-to-site VPN is a type of VPN connection that connects two or more networks across several locations.

Here we explain site-to-site VPNs, how they work, and whether it is suitable for your business.

What is a Site-to-Site VPN?

A site-to-site VPN is a connection created between two or more networks. It helps connect two or more geographically distant locations, such as central office and branch offices, and keep data encrypted between them without any client apps or credentials on the devices.

The site-to-site VPNs are valuable tools for organizations that prioritize private and protected traffic and are particularly useful to companies with multiple offices spread out over geographical locations.

Such organizations often have their resources on a primary network containing servers that host data and applications. In this case, a site-to-site VPN provides all the sites complete access to the application as if it was hosted on the physical facility itself.

For example, a business operating offices in New York, Texas, and California implements a site-to-site VPN to connect these locations. Such a setup creates a wide area network where users can easily exchange data with others in a secured manner. The VPN acts as a gateway and encrypts data, so users can function normally without having to install or manage any software.

Types of VPNs

Virtual private networks can be of several types, each serving a distinct purpose based on the organization’s needs.

Remote Access VPN

A remote-access VPN is a temporary connection established between the central location and multiple users. This type of VPN is generally used to access company held data remotely.

Users can connect to a remote access VPN when they need access to sensitive information on the company servers. This way, each employee can get easy access to the resources they need to perform their tasks.

A remote-access VPN helps provide workers across locations an experience that resembles being in the central office to connect to the server using an Ethernet cable. In other words, this VPN extends the cable across international borders to reach employee workstations, including desktops, laptops, and mobile devices.

Intranet-Based Site-to-Site

An intranet-based site-to-site VPN is a wide area network formed by connecting multiple local area networks. Companies with several offices use VPN to securely pool resources housed in different locations as if they were all in a single physical place. An organization can also use such a setup to implement SD-WAN (Software-defined WAN).

A site-to-site VPN is beneficial when every site has its processes or resources that the whole organization needs to access. For example, if an intranet-based site-to-site VPN is set up across multiple business offices, each of them could access design schematics updated for the customers, irrespective of their physical location.

Extranet-Based Site-to-Site

This type of VPN is generally used between companies that want to share some resources while maintaining security and privacy for others. Each site on an extranet-based site-to-site VPN connects to the network and selects what they want to share with other sites. In this way, they can share and collaborate with others without exposing internal data.

Benefits of Site-to-Site VPN

Many businesses have many physical locations, each with its own corporate local area network (LAN). Despite their geographical separation, these many sites require a unified corporate WAN to enable safe cross-site communication.

A site-to-site virtual private network (VPN) does this by establishing an encrypted connection between VPN gateways placed at each of these locations. A site-to-site VPN tunnel encrypts communication at one end and transfers it across the internet to the other site.  Here, the data is decrypted and directed to its destination.

Site-to-Site VPNs provide several benefits to enterprises and their employees, such as:

• Encrypted Traffic: All traffic passing over a site-to-site VPN is encrypted, meaning all business data transmitted over the public internet is encrypted, preventing eavesdropping and manipulation.
• Simplified Network Architecture: Internal IP address ranges are routinely used by organizations for devices within their LANs. These addresses must be translated to external IP addresses. Traffic from one LAN to another stays “internal” with site-to-site VPNs, which means that all sites can utilize internal addresses for each other’s resources.
• Access Control: Some network resources are only designed to be accessible internally, which means that staff at different locations should have access but not external users. Because site-to-site VPN users are “internal,” access control rules are easier to define because any traffic that does not originate within the network or enter via VPN tunnels can be banned from accessing these resources.

Factors to consider when deploying a Site-to-Site VPN

A site-to-site VPN securely connects your LANs – no matter where they are – to provide employees at all LAN sites with secure access to the entire network’s resources.

A site-to-site VPN has numerous benefits for a moderately large organization.  However, it does require a significant investment in terms of money and human resources.

Here are some essential aspects of site-to-site VPNs that should be considered:

Watertight Security

When an organization uses site-to-site VPN, it expects highly secure protection as far as the data is concerned. The rising scenario of cyberattacks makes security prominent for business owners. Using a VPN can give peace of mind, knowing that robust security protocols protect data transfer between locations.

A VPN uses authorization, administration, and authentication processes to ensure a satisfactory level of security. All the business processes must support these security policies, including IT best practices developed by internal departments across locations. A well-configured VPN allows authenticated data to enter, block unauthorized access, and keep the network safe.

Simple to Scale

A significant benefit of using a site-to-site VPN for an organization is scalability. When you open a new office or branch, it is easy to add it to the WAN instead of having to set up each device and get it running individually.

Operational Efficiency

If a network is not easy to use, it can result in frustration instead of convenience. Employees should be able to access it easily through a web browser. They don’t need to deal with any client apps on their systems; they log on, and the gateway does the rest.

Though it is essential to ensure ease of access, it should not result in compromised security. If users need to go through an extra step to access their VPN, it is worth spending those few additional minutes to ensure best security practices. However, any security practices should not be cumbersome either, and users should be able to remotely access data using their tablets and smartphones.

VPNs should also make the job of network administrators easier. The administrator can manage all the locations from the central office and take control over the whole network, giving them the flexibility to add new security features and update existing solutions from a single location.

Business Continuity

In the event of a disaster, it is desirable to minimize interruption to the business operations and get them running at the earliest to reduce downtime. A site-to-site VPN makes this possible through immediate remote access once an emergency has been detected.

For example, if a disaster hits an office, employees need not stop the operations till things get back to normal. They can access the site-to-site VPN to use the resources at the central office and start working from home. A virtual private network thus helps reduce the effects of a disaster and minimize downtime and loss.

Flexible Deployment

A VPN enables you to deploy any new solution across a network of devices at multiple locations. It also allows sites to be prioritized based on needs, ease, and other factors when deciding which sites get the solution. Such an approach ensures support and training can be provided in a controlled manner rather than overloading your IT team suddenly.

Does your Business need a Site-to-Site VPN?

Several factors need to be considered to determine whether you should implement a site-to-site VPN for your business.

A standard IPsec may suffice for communication between two offices in most cases. However, certain factors drive the need for a site-to-site VPN for a company:

• Number of locations
• Size of the business
• Distance between two locations
• Resources shared between locations
• Sensitivity of data being transmitted

For a small business operating in a single office with little to no data shared outside of the premises, a site-to-site VPN is not at all a necessity. However, if the business aspires to grow into a larger entity across multiple locations or is already operating in several places, a site-to-site VPN can prove to be a sensible option for its present and future.

A critical consideration is the security of data. For businesses in industries like finance and healthcare, protecting data is highly crucial, and any compromise with customer records can be dangerous. This is true for companies operating in other verticals where vast volumes of customer data are handled. They can encounter hefty penalties in the absence of proper security measures in place.

Why may a Site-to-Site VPN not be suitable for your business?

Businesses have been traditionally using site-to-site VPNs to connect their remote offices with the central hub. However, the approach works better when the organization has an in-house data center or deals with highly sensitive applications.

Now that most companies are moving their data and applications to the cloud and working across large mobile workforces, they need to create a topology to access the cloud. This shift in operations drives network architectures that don’t involve bringing the traffic back to the central office.

This is why several businesses are shifting away from site-to-site VPNs and looking for other options depending on their needs. A remote-access VPN works much like the site-to-site VPN and might be a better option for you if you are looking to protect data used by remote workers. This type of network allows employees to access data from anywhere using an internet connection.

Another emerging solution is SASE (Secure Access Service Edge) to serve companies hosting data on the cloud. This platform offers a remote access VPN loaded with firewall security features such as web filtering, DNS security, advanced threat protection, and more.

A SASE option gives you all the benefits of a network connection through a cloud, easing any concerns about remote data security.

While site-to-site VPNs are great options for businesses operating across multiple offices, a remote access VPN might better suit offices with remote employees, and a combination of the two is perfect for companies that have both.