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2.4.1.2 SegmentDescription

Each SegmentDescription describes a single segment. Each segment's description chunk MUST contain at least one segment description. A segment description chunk can contain multiple segment descriptions.

Segments MUST be listed in the Content Information in the same order as they appear in the content.


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cbSegment

SegmentHashOfData (32 bytes)

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SegmentSecret (32 bytes)

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cbSegment (4 bytes): Total number of bytes in the segment, regardless of how many of those bytes intersect the content range. The value of this field MAY not be zero and MAY not exceed 128 kilobytes.

SegmentHashOfData (32 bytes): The hash of the segment. The hash is of length 32 bytes if the value of bHashAlgo field (section 2.4) at the start of the Content Information was 0x04 = truncated SHA-512. Truncated SHA-512 is the only supported hash algorithm.

SegmentSecret (32 bytes): Kp (section 2.2), computed as Hash (SegmentHashofData + ServerSecret) using the hash algorithm specified at the beginning of the Content Information Data Structure. The hash is of length 32 bytes if the value of bHashAlgo field (section 2.4) at the start of the Content Information was 0x04 = truncated SHA-512. Truncated SHA-512 is the only supported hash algorithm.