Abstract:

The key agreement protocol is a shared key mechanism between two or more participants in a public channel to ensure the secure communication and encryption of sensitive information. Communication agents need to trust each other, and a trusted center is needed to authenticate each other to negotiate the key securely. In order to resist the attack on the trusted center and the abuse of power of the trusted center, this paper gives a multi-parties key agreement protocol in block chain system, which uses the characteristics that when store data, data only can increase, but can not be deleted and changed, which makes the protocol more secure.

Key words: multi-parties key agreement protocol, bilinear pairing, block chain, trusted third party