Vpn over TCP or UDP

A VPN is for wrapping raw IP packets into some kind of “tunnel” between two sites.

– Connection speed  is  going slow down  cause of  Encryption.

Performance :    UDP is better

Security        :   For  Experts  ,  it is  The same .   UDP is also secure, because  VPN service  adding  EXTRA header  inside of  UDP

Connectionless  >  TCP is a protocol which sits on top of IP,   (which are “unreliable“: Packet  lost, duplicated, reordered)

 

to provide a reliable two-directional channel for data bytes, where bytes always reach the receiver in the order they were sent. TCP does that by using a complex assortment of metadata with explicit acknowledges and reemissions. Thus, TCP incurs a slight network overhead.

If VPN uses TCP,  it is paying the TCP overhead twice. An UDP-based VPN thus has the potential for slightly better performance. On the other hand, the cryptographic protection of the VPN requires some state management, which may be harder for the VPN implementation when using UDP, hence it is possible that the UDP-based VPN has an extra overhead to contend with.

Performance  is tested by me, and  UDP connection performance obviously better than TCP.

 

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