Red Hat, Inc acquired Qumranet in 2008, and in December 2009 released the code under an open-source license and made the protocol an open standard.
A data channel can be designated to operate in either clear-text, or TLS modes, allowing the administrator to trade off the security level vs performance.
The TLS mode provides strong encryption of all traffic transmitted on the data channel.
The original SPICE protocol defined a ticket based authentication scheme using a shared secret.
The SPICE protocol originated to provide improved remote desktop capabilities in a fork of the KVM codebase.