This thesis deals with implementation of the ZRTP protocol,
which is used for the key agreement between two endpoints in
VoIP.
In this thesis, the protocol is compared with other
technologies,
that are used for the same purpose. The whole process of the
protocol is described in detail. The thesis includes
description of my protocol implementation and test framework,
which demonstrates the functionality of the implementation. The
practical part of the thesis is available under BSD license and
included in the attachment.