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What is TUN tap driver?
TUN/TAP provides packet reception and transmission for user space programs. When the program closes the file descriptor, the network device and all corresponding routes will disappear. Depending on the type of device chosen the userspace program has to read/write IP packets (with tun) or ethernet frames (with tap).
What tun and TAP devices can be used for?
TUN/TAP is used to provide packet reception and transmission for user space programs. TUN stands for network TUNnel) is a network layer device and TAP stands for network TAP and it is a link layer device and both of them are virtual network kernel devices.
What does TAP adapter mean?
The TAP-Windows Adapter is a network driver, used by VPN services to connect to servers. This means that for most VPN clients (ExpressVPN, NordVPN, CyberGhost, etc.) it’s a needed component to install on your device.
What is a VPN tap adapter?
The TAP-Windows Adapter is a network driver, used by VPN services to connect to servers. This means that for most VPN clients (ExpressVPN, NordVPN, CyberGhost, etc.) If you use a browser extension VPN, you won’t come across it, but won’t have the benefits of a full-feature VPN client installed on your system directly.
How does a TUN / TAP interface work?
TUN/TAP provides packet reception and transmission for user space programs. It can be seen as a simple Point-to-Point or Ethernet device, which, instead of receiving packets from physical media, receives them from user space program and instead of sending packets via physical media writes them to the user space program.
How does the Linux kernel handle the TAP device?
The application encrypts, compresses and sends it to the other side over TCP or UDP. The application on the other side decompresses and decrypts the data received and writes the packet to the TAP device, the kernel handles the packet like it came from real physical device.
What’s the difference between tap and tun in Linux?
TUN works with IP frames. TAP works with Ethernet frames. This means that you have to read/write IP packets when you are using tun and ethernet frames when using tap. What is the difference between BPF and TUN/TAP driver?
How does Multiqueue tuntap work in Linux kernel?
From version 3.8, Linux supports multiqueue tuntap which can uses multiple file descriptors (queues) to parallelize packets sending or receiving. The device allocation is the same as before, and if user wants to create multiple queues, TUNSETIFF with the same device name must be called many times with IFF_MULTI_QUEUE flag.