Adjustable Two-Tier Cache for IPTV Based on Segmented Streaming

Abstract

Internet protocol TV (IPTV) is a promising Internet killer application, which integrates video, voice, and data onto a single IP network, and offers viewers an innovative set of choices and control over their TV content. To provide high-quality IPTV services, an effective strategy is based on caching. This work proposes a segment-based two-tier caching approach, which divides each video into multiple segments to be cached. This approach also partitions the cache space into two layers, where the first layer mainly caches to-be-played segments and the second layer saves possibly played segments. As the segment access becomes frequent, the proposed approach enlarges the first layer and reduces the second layer, and vice versa. Because requested segments may not be accessed frequently, this work further designs an admission control mechanism to determine whether an incoming segment should be cached or not. The cache architecture takes forward/stop playback into account and may replace the unused segments under the interrupted playback. Finally, we conduct comprehensive simulation experiments to evaluate the performance of the proposed approach. The results show that our approach can yield higher hit ratio than previous work under various environmental parameters.

Cooperative Announcement-Based Caching for Video-on-Demand Streaming

“…In this paper we focus on reactive caching approaches leveraging video structure and request announcements rather than proactively placing content into network caches. Other approaches use a two-tier cache that distinguishes between to-be-played and possibly played segments, partitioning the cache in two layers that are dynamically scaled [11]. The approach of dynamic cache partitioning has also been applied by Wauters et al, where caching decisions in a time-shifted television service are based on content popularity metrics [12].…”

“…The segment s is selected as the segment with the maximal earliest reuse time: s = arg max v i ∈C∪{vx} e v i (lines 5-7). When multiple such segments exist, the LRU order is used as a tiebreaker (lines [8][9][10][11]. When the evicted segment s is a cached segment (s ∈ C), it is removed from the cache and replaced by the new segment v x (lines [16][17][18] Remove s from C…”

An announcement-based caching approach for video-on-demand streaming

“…In this paper we focus on reactive caching approaches leveraging video structure and request announcements rather than proactively placing content into network caches. Other approaches use a two-tier cache that distinguishes between to-be-played and possibly played segments, partitioning the cache in two layers that are dynamically scaled [9]. The approach of dynamic cache partitioning has also been applied by Wauters et al, where caching decisions in a time-shifted television service are based on content popularity metrics [10].…”