Today we continue to discuss the streaming proxy design. We were discussing  to improve tje lazy segmentation strategy.  The replacement policy involves evicting the least useful media object segments. This can be done in one of three different phases. the first phase is when the object is fully cached. the second phase is when the object is partially cached with more than one segment. The third phase is when the object is partially cached with only one segment. The utility value of each object is updated after each replacement and this process repeats iteratively until the required space is found.
We now discuss the hyper proxy system where the authors co-ordinate the two schemes discussed earlier.
For every media object accessed through the proxy, a data structure is maintained which is called the access log of the object. This data structure has fields for such things as the length of the base segment, the number of cached segments of the object, the threshold length used in the replacement policy and the average access duration of an object.  The threshold length is calculated for each object as per the three phase technique above. In this system, there are two lists maintained, the basic list and the premium list. The basic list contains all objects whose length of cached segment is larger than the length of all its threshold length while the premium list contains those objects whose cached data length is equal to or less than the threshold length.  A flag is used to determine the priority at admission. The admission policy dictates that the object is fully cached until it is chosen as an eviction item. At that time, some of the segments are evicted, the object is also transferred to the premium list.  When the object is accessed again,  the segments of the object are adaptively admitted by the admission policy or adaptively replaced by the replacement policy