IMU: A Content Replacement Policy for CCN, Based on Immature Content Selection

Abstract

In-network caching is the essential part of Content-Centric Networking (CCN). The main aim of a CCN caching module is data distribution within the network. Each CCN node can cache content according to its placement policy. Therefore, it is fully equipped to meet the requirements of future networks demands. The placement strategy decides to cache the content at the optimized location and minimize content redundancy within the network. When cache capacity is full, the content eviction policy decides which content should stay in the cache and which content should be evicted. Hence, network performance and cache hit ratio almost equally depend on the content placement and replacement policies. Content eviction policies have diverse requirements due to limited cache capacity, higher request rates, and the rapid change of cache states. Many replacement policies follow the concept of low or high popularity and data freshness for content eviction. However, when content loses its popularity after becoming very popular in a certain period, it remains in the cache space. Moreover, content is evicted from the cache space before it becomes popular. To handle the above-mentioned issue, we introduced the concept of maturity/immaturity of the content. The proposed policy, named Immature Used (IMU), finds the content maturity index by using the content arrival time and its frequency within a specific time frame. Also, it determines the maturity level through a maturity classifier. In the case of a full cache, the least immature content is evicted from the cache space. We performed extensive simulations in the simulator (Icarus) to evaluate the performance (cache hit ratio, path stretch, latency, and link load) of the proposed policy with different well-known cache replacement policies in CCN. The obtained results, with varying popularity and cache sizes, indicate that our proposed policy can achieve up to 14.31% more cache hits, 5.91% reduced latency, 3.82% improved path stretch, and 9.53% decreased link load, compared to the recently proposed technique. Moreover, the proposed policy performed significantly better compared to other baseline approaches.

NDN Content Store and Caching Policies: Performance Evaluation

“…Figure 5 shows the result of the aforementioned simulation, which is similar to the result achieved earlier and presented in Figures 2b and 3 The results presented in this section are particularly inconsistent with those achieved in [5], where the network performance in terms of CHR increases when the number of CS increases up to about 40% and then decreases with the number of CS above this threshold. However, the results are consistent with ones achieved in [6], where the CHR increases with the continuous increasing in the number of CS, or in [7][8][9][10][11][12][13][14][15][16]50] which evaluate the network performance with a constant number of CS but different sizes.…”

“…The authors concluded that the proposed solution presents better performance than others in terms of the chosen metrics. The immature used (IMU) replacement policy was proposed in [15]. Besides the popularity, the proposal resorts to the content maturity index, which is calculated by using the content arrival time and its frequency within a specific time frame.…”

“…Consumers request content at a rate of 1000 packets/s. All the other selected studies ( [10][11][12][13][14][15][16]) present a fixed number of CS, only varying the size of the deployed CS, and compare the performance of their proposed solution with some of the state-of-the-art methods, as presented in the table.…”

“…Although this work does not perform an exhaustive survey on similar studies, some representative proposals can be found in [5,6] for performance evaluation on a caching system with a variable number of CS, or in [7][8][9][10][11][12][13][14][15][16] for evaluation with a variable size of a fixed number of CS, as presented in Section 4. A survey on replacement schemes, which can complement this Section, is performed in [17].…”

A survey of classification cache replacement techniques in the contentcentric networking domain

“…However, balancing between content popularity and cache gain can complicate eviction decisions, such as when a higher cache gain increases the perceived value of less popular content. Rashid et al (2021) proposed another cache replacement policy for content-centric networks named Immature Used (IMU). This policy aims to address the issue of holding onto currently unpopular content and prematurely evicting potentially popular content.…”