What is IPsec?

Internet Protocol Security, or in short IPsec, is a group of network protocols used for authenticating and encrypting data transferred over public networks. The IPsec protocol suite is one of the two protocols used in VPNs. The other is called Transport Layer Security (TLS), and it is a newer version of the old Secure Sockets Layer (SSL). Although TSL is a newer standard, the two protocols have many similarities, so they are usually encountered in documentation as TLS/SSL.

While TSL/SSL protocols are using encryption to secure applications, IPsec was designed to secure networks. Initially, it was a requirement for IPv6 addresses, but the slow adoption of IPv6 made IPsec common also for IPv4 addresses. To find out more about IP addressed and the difference between IPv6 and IPv4, read our entry on IP.

How does IPsec work?

Data transmitted over the internet is split into multiple bits called packets. The content of the packet is called payload, and information about the packet, the meta-data, is called header. IPsec encrypts both the payload and the header for each package. Data packages are then transmitted through the network using a transport protocol, and once they arrive at the destination, they are decrypted. Encryption requires cryptographic keys and cryptographic algorithms. The keys transform plaintext (including bits) into ciphertext, and the algorithm provides the method for encrypting and decrypting data. When a sender and a receiver establish a connection, they first have to exchange keys. An IPsec connection is established in six steps:

1. Setting up the key exchange between devices

2. Adding headers and trailers to data packets

3. Providing authentication for data packets

4. Encrypting the data packets

5. Transmitting the data packets

6. Decrypting the data packets upon delivery

Avira Phantom VPN supports both IPsec and SSL/TSL protocols. For computers and laptops running Windows and macOS, as well as for Android devices, our VPN uses the SSL/TSL protocols based on the OpenVPN open-source software. For iOS devices and applications from the AppStore and Microsoft Store, Avira Phantom VPN is using the IPsec protocol.

Learn more about VPNs:

What is a VPN?

How to use a VPN for anonymous browsing?

How to bypass heo-restrictions with a VPN?

Important: Your current Windows version is outdated and no longer supported.
For your security, we recommend switching to Windows 10 before downloading Avira software.
Update your Windows version here.
Wichtig: Ihre Windows-Version ist veraltet und wird nicht mehr unterstützt.
Zu Ihrer Sicherheit empfehlen wir Ihnen den Wechsel zu Windows 10 vor dem Download unserer Software.
Hier können Sie Ihr Windows aktualisieren.
Important: Votre version actuelle de Windows est obsolète et n’est plus prise en charge.
Pour votre sécurité, nous vous conseillons de passer à Windows 10 avant de télécharger le logiciel Avira.
Mettez à jour votre version de Windows ici.
Importante: Tu versión actual de Windows está desactualizada y ya no es compatible.
Por tu seguridad, te recomendamos que instales Windows 10 antes de descargar la solución de Avira.
Actualiza aquí tu versión de Windows.
Importante: La tua attuale versione di Windows è obsoleta e non è più supportata.
Per la tua sicurezza, ti consigliamo di passare a Windows 10 prima di scaricare i software Avira.
Aggiorna la tua versione di Windows qui.
Importante: Sua versão atual do Windows está desatualizada e não tem mais suporte.
Para sua segurança, recomendamos que troque para o Windows 10 antes de baixar o software da Avira.
Atualize sua versão do Windows aqui.
Важно: ваша версия Windows устарела и больше не поддерживается.
Из соображений безопасности перед загрузкой ПО Avira мы рекомендуем перейти на Windows 10.
Обновить Windows вы можете здесь.
Belangrijk: Uw huidige versie van Windows is verouderd en wordt niet meer ondersteund.
Voor uw veiligheid adviseren wij u om over te stappen op Windows 10 voordat u de Avira-software downloadt.
Update uw Windows-versie hier.
Önemli: Kullanmakta olduğunuz Windows sürümü eski ve artık desteklenmiyor.
Güvenliğiniz için Avira yazılımını indirmeden önce Windows 10 sürümüne yükseltmenizi öneririz.
Windows sürümünü buradan güncelleyin.
重要 : 現在お使いの Windows バージョンは古いため、サポートされなくなりました。
安全のため、Avira ソフトウェアをダウンロードする前に Windows 10 に切り替えることをお勧めします。
こちらより Windows バージョンをアップデートしてください
重要信息 : 您当前的 Windows 版本已过时,并且不再受支持。
为了安全起见,我们建议您在下载 Avira 软件之前切换到 Windows 10。
在此升级您的 Windows 版本
重要資訊 : 您當前的 Windows 版本已過時,並且不再受支援。
為了安全起見,我們建議您在下載 Avira 軟體之前切換到 Windows 10。
在此升級您的 Windows 版本