Fast Switching Technology
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Fast Switching Technology from Gefen
Gefen created FST because HDMI switching time was too slow for many of installers, who demanded a faster switching time with no picture flickering between switches.
When selecting from one of several sources all connected to an HDTV display, installers want and instant delivery of audio/video. When sources and displays use HDMI with HDCP (high-bandwidth digital content protection), there can be a delay as HDCP handshaking takes place.
For years, Gefen has been challenged to support systems using the inherited limitations of HDMI. Customers have long requested Gefen to create a new ecosystem enabling fast switching and distribution when using HDMI.
In 2010, Gefen announced its new Fast Switching Technology (FST) to reduce HDCP handshaking time, dramatically improving system performance. The main FST requirement was to implement a technology that is as fast and efficient in all signal switching and distribution as with previous generations of analog systems.
FST is a Gefen software implementation on all its HDMI v1.3 products, including matrixes, switchers, splitters and distribution amplifiers. It improves inherited HDCP handshaking based on HDMI specifications. It also improves overall system performance when more than one HDTV display is used in the system, making it ideal for digital signage. FST allows installers to connect/disconnect and turn on/off HDTV displays without affecting other sources routed to HDTV displays in the same system.
FST works by bypassing repetitive HDCP handshaking requirements. HDCP involves the implementation of key chain links in HDMI chips originating from the source. The HDCP-enabled source is responsible for confirming that all devices in the same key chain are legitimate HDCP devices.
When equipped with FST, Gefen’s switchers, matrixes, splitters, and distribution amps are responsible for reporting to the source all devices included in the key chain. This reporting is completed by a link chain handshaking process, during which there can be an interruption in audio/video. The length of this interruption depends upon the speed of the handshake between the source and all other sink devices in the same link chain.
FST dramatically shortens the handshaking time even when handshaking is requested from the source every time a switch or HPD (Hot Plug Detect) occurs.
The FST software is very smart and can bypass the handshaking every time a switch or HPD occurs except for the first time the system is turned on.
FST is now a standard in all new Gefen HDMI v1.3 and above products. Older HDMI versions cannot be upgraded to FST.