Click here

IPsec

Short for IP Security, a set of protocols developed by the IETF to support secure exchange of packets at the IP layer. IPsec has been deployed widely to implement Virtual Private Networks (VPNs).

IPsec supports two encryption modes: Transport and Tunnel. Transport mode encrypts only the data portion (payload) of each packet, but leaves the header untouched. The more secure Tunnel mode encrypts both the header and the payload. On the receiving side, an IPSec-compliant device decrypts each packet.

For IPsec to work, the sending and receiving devices must share a public key. This is accomplished through a protocol known as Internet Security Association and Key Management Protocol/Oakley (ISAKMP/Oakley), which allows the receiver to obtain a public key and authenticate the sender using digital certificates.



Top Terms

Connect with Webopedia

  • What is 250 GB Data Usage?

    What is 250 GB (250 gigabytes) and why is this phrase so popular? Webopedia explains what the phrase 250 GB means in reference to data storage...

    Read More »

Did You Know? Archive »

  • Quick Reference Archive »