Site-to-Site VPN for Secure Connections Between Business Offices and Partners

As we have learned, a Virtual Private Network allows two networks to communicate securely across a public network. A VPN also enables a server-to-server connection, as opposed to a client-to-server connection, allowing two networks to establish an extended intranet or extranet. In this blog post, we will cover how we can connect distant branches of our company or partners securely with a site-to-site VPN.

What is a Site-to-Site VPN?

Site-to-site VPNs are typically built between corporate offices that are separated by a physical distance greater than that covered by standard local area network media.

The first step in setting up a site-to-site VPN is deciding which protocols to employ. Once we decide which protocol to use, two networks are linked together as though they were one. Devices on one network can safely connect with any device on another network.

How does a site-to-site VPN work?

When data leaves one network, it is sent across the secure VPN tunnel. The VPN gateway of the remote department arranges a connection with the VPN gateway of another department network. They form a secure way of communication called tunneling. The gateway authenticates users and networks and encrypts and preserves the integrity of data.

When the virtual private network gateway gets ciphered data, it removes the headers, decodes what it includes, and sends the decrypted data to the network’s recipient. A VPN makes an organization’s system and logical properties accessible to a distant branch. Site-to-site VPNs are classified into two types: intranet-based and extranet-based.

Intranet-based VPN

You can use this type of connection if you have a small number of distant offices and want to connect them all together to form a single network. A continuous link is created between all of your company’s distant branches, allowing for the sharing of systems and network resources. This provides the impression that all of the numerous networks of the various branches are part of a single network.

Extranet-based VPN

Let’s say you are a corporation and want to connect to the network of a partner. Your company’s local area network (LAN) is linked to your partner’s LAN in order to transfer specific information between the firms. This will improve business ties and procedures. Here are some other examples of an extranet-based VPN:

  • In the event of a supply chain partnership, for example, corporations let their partners join their network in order to exchange the database and other important information.

  • Companies can use the extranet-VPN to exchange certain information with their partners, such as client database applications, and nothing else.

  • It enables businesses to collaborate in a safe and shared environment while keeping their internal network protected and accessible exclusively to internal users.


As we have covered, a site-to-site VPN is established between business offices and partners that are physically isolated. The site-to-site solution is ideal for small offices located in remote parts of the world. Since our major concern is security and access control, we can safely connect to any device on another network, like a private network.

However, there is a major challenge for network administrators. Setting up a site-to-site VPN and then ignoring other forms of protection is a typical error. Users on distant networks should not be able to reach the local network assets without a proper access control mechanism, and vice versa. This can be challenging in some circumstances, especially if the remote office is another organization, such as a vendor or a partner.

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