[Design View / Design Solution]
Get The MOST Out Of Your Automotive Communications
The MOST network protocol for cars offers support for music, video, telecom, and anything else engineers can imagine.
As a result, the new generation of MOST provides the automotive-ready physical layer for Ethernet in the car. In addition, MOST Specification Rev. 3.0 offers an isochronous channel to support streams that aren’t synchronized to the MOST frame rate. A typical usecase is the transport of MPEG streams over a MOST network, since MPEG streams generally use variable bit rates. This new MOST feature enables extensive video applications.
MOST Specification Rev. 3.0 also adds significant enhancements to the control channel. By doubling the bandwidth of that available with MOST25, the channel can control devices in real time.
With the integration of DVD audio and DVD video into digital networks, content protection becomes a requirement. DVD content on a digital network must be DTCP-protected (Fig. 3). HD DVD and Blu-ray content over MOST is also supported. That’s because Advanced Access Content System (AACS) specifications allow for DTCP-protected digital outputs.
DTCP requires source and sink devices to authenticate each other, and there’s a need to encrypt multimedia streaming data before sending it over a digital network. A sink device, then, must be able to decrypt protected digital content. DTCP on MOST also supports point-to-multipoint connections. The single phases consist of authentication (32-bit public device key), key exchange (Elliptic Curve DH), and encryption and decryption (M6-56Bit, AES-128Bit).
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