2.2.1.5 ENCODED_SEGMENT_AGE

An ENCODED_SEGMENT_AGE is an array of four bytes that describes the age of a segment of data involved in a Peer Content Caching and Retrieval: Retrieval Protocol message exchange. The age refers to the amount of time that has elapsed since the specified segment was first created in the local BranchCache cache.


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SegmentIndex

SegmentAgeLowPart

SegmentAgeMidPart

SegmentAgeHighPart

SegmentIndex (1 byte): Index of a segment among all of the segments involved in the current message exchange. The index is relative to the first segment addressed in the message containing the specific current ENCODED_SEGMENT_AGE structure.

SegmentAgeLowPart (1 byte): Low part of the age of the segment.

SegmentAgeMidPart (1 byte): Mid part of the age of the segment.

SegmentAgeHighPart (1 byte): High part of the age of the segment.

The actual age of the segment is calculated as: SegmentAgeLowPart + 256 * SegmentAgeMidPart + 256 * 256 * SegmentAgeHighPart.

The age of the segment is expressed according to the unit specified in the enclosing object/message. If no enclosing object/message is available, the age MUST be specified (and is assumed to be specified) in hundredths of milliseconds.