On-path Caching Research Articles

RMBCC: A Replica Migration-Based Cooperative Caching Scheme for Information-Centric Networks

How to maximize the advantages of in-network caching under limited cache space has always been a key issue in information-centric networking (ICN). Replica placement strategies aim to fully utilize cache resources by optimizing the location and quantity distribution of replicas in the network, thereby improving the performance of the cache system. However, existing research primarily focuses on optimizing the placement of replicas along the content delivery path, which cannot avoid the inherent drawback of not being able to leverage off-path cache resources. The proposals for off-path caching cannot effectively solve this problem as they introduce excessive complexity and cooperation costs. In this paper, we address the trade-off between cache resource utilization and cooperation costs by introducing a mechanism complementary to replica placement. Instead of redesigning a new caching strategy from scratch, we propose a proactive cooperative caching mechanism (called RMBCC) that involves an independent replica migration process, through which we proactively relocate replicas evicted from the local cache to neighboring nodes with sufficient cache resources. The cooperation costs are effectively controlled through migration replica filtering, migration distance limitation, as well as hop-by-hop migration request propagation. Extensive simulation experiments show that RMBCC can be efficiently integrated with different on-path caching strategies. Compared with representative caching schemes, RMBCC achieves significant improvements in evaluation metrics such as cache hit ratio and content retrieval time, while only introducing negligible cooperation overhead.

ENCache: Improving content delivery with cooperative caching in Named Data Networking

Content centric networks offer better response time and resilience to failures by caching the content in the network routers. Owing to the limited capacity of caches and the quest for maximizing the utilization of available caches has lead to many interesting caching techniques. While on-path caching is a commonly adopted caching technique to reduce content access latency, it does not guarantee better cache hit ratio when considered across multiple receivers in the network. In this paper, we present eNCache which is a cooperative caching method that cooperates among the routers in the neighborhood to improve overall performance. It retains the simplicity of on-path caching and makes caching, routing (queries and replies) decisions by interacting with off-path routers in the neighborhood. We present the working of eNCache with algorithms for request handling and caching decisions at every router. We also formalize the interaction between a router and its neighbors by providing an extension to the Named Data Networking Interest packet structure. We evaluate and compare the performance of eNCache with other popular on-path caching strategies by performing simulations on standard RocketFuel Internet Service Provider (ISP) topologies using a discrete event simulator. We also compare the performance of a variant of enhanced NCache, i.e.,eNCache with hash based off-path caching methods. Our simulation results show that eNCache has reduced latency, better cache hit ratio and diversity.

Blockchain-Enabled On-Path Caching for Efficient and Reliable Content Delivery in Information-Centric Networks

As the demand for online content continues to grow, traditional Content Distribution Networks (CDNs) are facing significant challenges in terms of scalability and performance. Information-Centric Networking (ICN) is a promising new approach to content delivery that aims to address these issues by placing content at the center of the network architecture. One of the key features of ICNs is on-path caching, which allows content to be cached at intermediate routers along the path from the source to the destination. On-path caching in ICNs still faces some challenges, such as the scalability of the cache and the management of cache consistency. To address these challenges, this paper proposes several alternative caching schemes that can be integrated into ICNs using blockchain technology. These schemes include Bloom filters, content-based routing, and hybrid caching, which combine the advantages of off-path and on-path cachings. The proposed blockchain-enabled on-path caching mechanism ensures the integrity and authenticity of cached content, and smart contracts automate the caching process and incentivize caching nodes. To evaluate the performance of these caching alternatives, the authors conduct experiments using real-world datasets. The results show that on-path caching can significantly reduce network congestion and improve content delivery efficiency. The Bloom filter caching scheme achieved a cache hit rate of over 90% while reducing the cache size by up to 80% compared to traditional caching. The content-based routing scheme also achieved high cache hit rates while maintaining low latency.

PB-NCC: A Popularity-Based Caching Strategy with Number-of-Copies Control in Information-Centric Networks

The Information-Centric Network (ICN), designed for efficient content acquisition and distribution, is a promising candidate architecture for the future Internet. In-network caching in ICN makes it possible to reuse contents and the Name Resolution System (NRS) makes cached contents better serve users. In this paper, we focused on the ICN caching scenario equipped with an NRS, which records the positions of contents cached in ICN. We propose a Popularity-based caching strategy with Number-of-Copies Control (PB-NCC) in this paper. PB-NCC is proposed to solve the problems of unreasonable content distribution and frequent cache replacement in traditional caching strategies in ICN. We examine PB-NCC with a large number of experiments in different topologies and workloads. The simulation results reveal that PB-NCC can improve the cache hit ratio by at least 8.85% and reduce the server load by at least 11.34% compared with other on-path caching strategies, meanwhile maintaining a low network latency.

COCP: Coupling Parameters Content Placement Strategy for In-Network Caching-Based Content-Centric Networking

On-path caching is the prominent module in Content-Centric Networking (CCN), equipped with the capability to handle the demands of future networks such as the Internet of Things (IoT) and vehicular networks. The main focus of the CCN caching module is data dissemination within the network. Most of the existing strategies of in-network caching in CCN store the content at the maximum number of routers along the downloading path. Consequently, content redundancy in the network increases significantly, whereas the cache hit ratio and network performance decrease due to the unnecessary utilization of limited cache storage. Moreover, content redundancy adversely affects the cache resources, hit ratio, latency, bandwidth utilization, and server load. We proposed an in-network caching placement strategy named Coupling Parameters to Optimize Content Placement (COCP) to address the content redundancy and associated problems. The novelty of the technique lies in its capability to minimize content redundancy by creating a balanced cache space along the routing path by considering request rate, distance, and available cache space. The proposed approach minimizes the content redundancy and content dissemination within the network by using appropriate locations while increasing the cache hit ratio and network performance. The COCP is implemented in the simulator (Icarus) to evaluate its performance in terms of the cache hit ratio, path stretch, latency, and link load. Extensive experiments have been conducted to evaluate the proposed COCP strategy. The proposed COCP technique has been compared with the existing state-of-the-art techniques, namely, Leave Copy Everywhere (LCE), Leave Copy Down (LCD), ProbCache, Cache Less for More (CL4M), and opt-Cache. The results obtained with different cache sizes and popularities show that our proposed caching strategy can achieve up to 91.46% more cache hits, 19.71% reduced latency, 35.43% improved path stretch and 38.14% decreased link load. These results confirm that the proposed COCP strategy has the potential capability to handle the demands of future networks such as the Internet of Things (IoT) and vehicular networks.

Cache management for large data transfers and multipath forwarding strategies in Named Data Networking

Named Data Networking (NDN) is a promising approach to provide fast in-network access to compact muon solenoid (CMS) datasets. It proposes a content-centric rather than a host-centric approach to data retrieval. Data packets with unique and immutable names are retrieved from a content store (CS) using Interest packets. The current NDN architecture relies on forwarding strategies that are only dependent upon on-path caching. Such a design does not take advantage of the cached content available on the adjacent off-path routers in the network, thus reducing data transfer efficiency. In this work, we propose a software-defined, storage-aware routing mechanism that leverages NDN router cache-states, software defined networking (SDN) and multipath forwarding strategies to improve the efficiency of very large data transfers. First, we propose a novel distributed multipath (D-MP) forwarding strategy and enhancements to the NDN Interest forwarding pipeline. In addition, we develop a centralized SDN-enabled control for the multipath forwarding strategy (S-MP), which leverages the global knowledge of NDN network states that distributes Interests efficiently. We perform extensive evaluations of our proposed methods on an at-scale wide area network (WAN) testbed spanning six geographically separated sites. Our proposed solutions easily outperform the existing NDN forwarding strategies. The D-MP strategy results in performance gains ranging between 10.4x to 12.5x over the default NDN implementation without in-network caching, and 12.2x to 18.4x with in-network caching enabled. For S-MP strategy, we demonstrate a performance improvement of 10.6x to 12.6x, and 12.9x to 18.5x, with in-network caching disabled and enabled, respectively. Further, we also present a comprehensive analysis of NDN cache management for large data transfers and propose a novel prefetching mechanism to improve data transfer performance. Due to the inherent capacity limitations of the NDN router caches, we use SDN to provide an intelligent and efficient solution for data distribution and routing across multiple NDN router caches. We demonstrate how software-defined control can be used to partition and distribute large CMS files based on NDN router cache-state knowledge. Further, SDN control will also configure the router forwarding strategy to retrieve CMS data from the network. Our proposed solution demonstrates that the CMS datasets can be retrieved 28%–38% faster from the NDN routers’ caches than existing NDN approaches. Lastly, we develop a prefetching mechanism to improve the transfer performance of files that are not available in the router’s cache.

On-path caching based on content relevance in Information-Centric Networking

The Internet of things (IoT) is a new network concept. Based on the Internet, the idea of connecting everything is proposed, which is likely to become the development direction of computer and communication in the future. Meanwhile, as a disruptive new communication network model, Information-Centric Network (ICN) has become a hot spot in the field of future network architecture research in recent years. ICN is information-centric, and uses the name of the information to implement data identification, retrieval, and routing and forwarding. The information centric network uses the cache as a built-in structure, and nodes store all the data that flows by default, so that subsequent requests can be responded to as soon as possible. In the actual network, the spread and trend of an information constantly change with time, and the popularity of the information is different in different time periods. However, the existing ICN native caching mechanism ignores the correlation between contents, and the existing relevant research makes insufficient use of content relevance. In this paper may exist a certain correlation between nodes have access to the content of the facts, we design a path cache method based on the correlation content, by discovering target content and the correlation between nodes store content, at the same time considering the node position in the path, make caching decisions, make the cache memory more efficient. The feasibility and effectiveness of the proposed method are verified by simulation experiments under different parameters.

An On-Path Caching Scheme Based on the Expected Number of Copies in Information-Centric Networks

The Information-Centric Network (ICN) is one of the most influential future network architectures and in-network caching in ICN brings some helpful features, such as low latency and mobility support. How to allocate cache capacity and place content properly will greatly influence the performance of ICN. This paper focuses on the cache allocation problem and content placement problem under the given cache space budget. Firstly, a lightweight allocation method utilizing information of both topology and content popularity is proposed, to allocate cache space and get the expected number of copies of popular content. The expected number of copies represents the number of content copies placed in the topology. Then, an on-path caching scheme based on the expected number of copies is proposed to handle the content placement problem. In the cache allocation scenario, the lightweight allocation method performs better than other baseline methods. In the content placement scenario, Leave Copy Down (LCD) based on the expected number of copies performs the second-best and is very close to Optimal Content Placement (OCP).

A Lightweight Caching Decision Strategy Based on Node Edge-Degree for Information Centric Networking

In-network caching as a core function in ICN can greatly improve the content distribution efficiency and reduce redundant network traffic. It is a challenge to design caching strategies in ICN to improve the performance of in-network caching. Traditional lightweight strategies are inefficient due to problems such as edge caching pollution and slow diffusion speed. Current caching strategy with popularity prediction does not fully consider the content capacity of ICN network. They usually have huge computation overhead and cannot meet line-speed requirement. This paper focuses on the research of lightweight on-path caching. Our caching strategy is proposed according to the edge-degree of routers along the forwarding path. This strategy can quickly form a hierarchical content placement with little overhead. A large number of experiments are conducted to examine the performance of our strategy in different topologies and workloads. The simulation result reveals that our caching strategy can reduce the average download latency by 10.2% and increase the cache hit ratio by 9.6% at most compared with other lightweight strategies.

Improving mobile ad hoc networks using hybrid IP-Information Centric Networking

Routing protocols for Mobile Ad hoc NETworks (MANETs) constitute a research area with numerous evolved and well-investigated solutions that typically still rely on IP. Although IP-based protocols for MANETs can effectively handle network changes, thus enhancing connectivity while offering scalability, they lack support for advanced communication paradigms, which would enable richer applications and improve network goodput. Information-Centric Networking (ICN) is an inter-networking paradigm that natively supports functions that can enhance the performance of MANETs, such as multicast, multisource communication, and on-path caching. However, ICN raises significant scalability and feasibility concerns in the presence of intense node mobility. In this paper, we propose a hybrid architecture that combines the best of both worlds: it uses IP for maintaining network topology and it relies on ICN for content lookup and dissemination. To this end, we adapt the Named-Data Networking (NDN) ICN architecture to use legacy IP MANET routing protocols, such as Babel. Using a prototype implementation of our design and the Mininet Wi-Fi network emulator, we experimentally investigate the performance of our hybrid design in several scenarios, finding that the data delivery to network traffic ratio is increased up to 250% and 300% compared to pure NDN and IP solutions, respectively.

Service-aware optimal caching placement for named data networking

Built-in caching in Named Data Networking (NDN) promises to provide efficient content delivery, where the dedicated on-path caching scheme is deployed to serve users’ requests on the forwarding path. In this work, in order to utilize limited caching resources to achieve optimal performance, the caching placement decision is made by jointly considering the content popularity, underlying network topology, forwarding strategy, and on-path caching service mechanism in NDN. More specifically, we propose a service-aware caching model framework. In the model, we define the Caching Service Matrix (CSM), which describes the position where each user’s request is served for each piece of content. In order to make CSM comply with the caching placement, underlying topology, forwarding strategy, and on-path caching service mechanism, we propose two algorithms to calculate CSM under the preceding constraints. With CSM, we get a closed form expression of caching placement utility, and hence we formulate optimal caching placement into optimization problems. Moreover, considering the interdependency among the elements of the decision variable, we adopt the differential grouping co-evolutionary (DG2-E) algorithm to decompose and solve the problems. Simulation results show the proposed scheme outperforms conventional solutions in terms of inter-domain traffic saving and speed of response under both tree and arbitrary topologies.

Failure-Aware Protection for Many-to-Many Routing in Content Centric Networks

Network communications can easily be disrupted by the failure of networking equipment, ranging from a single accidental link cut, to a wide swath of links and nodes wiped out simultaneously by a natural disaster. To mitigate the impact of these failures, survivability solutions involving precomputed backup paths can be used to help maintain connectivity and reduce service downtime. Further improvements to reliability can be gained through the use of on-path caching inherent in Content Centric Networking (CCN). CCN is an alternative networking paradigm that puts the focus on efficiently providing consumers access over the network to content held by producers. As content is returned from a producer, it can be cached at the intermediate routers, allowing that content to be replicated and forwarded out to all known consumers asking for that content. We aim to improve the reliability of CCN by proposing routing algorithms for connecting many consumers to a set of producers with paths that are survivable in respect to a flexibly-sized failure set. These survivable routes are enhanced through the use of failure aware on-path caching that allows consumers to access content even after the primary connections to producers are severed.

Load Balancing in the Presence of Services in Named-Data Networking

Load balancing is a mechanism to distribute client requests among several service instances. It enables resource utilization, lowers response time, and increases user satisfaction. In Named-Data Networking (NDN) and NDN-like architectures, load balancing becomes crucial when dynamic services are present, where relying solely on forwarding strategies can overload certain service instances while others are underutilized especially with the limited benefit of on-path caching when it comes to services. To understand the challenges and opportunities of load balancing in NDN, we analyze conventional load balancing in IP networks, and three closely related fields in NDN: congestion control, forwarding strategies, and data center management. We identify three possible scenarios for load balancing in NDN: facade load balancer, controller for Interest queues, and router-based load balancing. These different solutions use different metrics to identify the load on replicas, have different compliance levels with NDN, and place the load balancing functionality in different network components. From our findings, we propose and implement a new lightweight router-based load balancing approach called the communicating vessels and experimentally show how it reduces service response time and senses server capabilities without probing.

Design of Multipath Transmission Control for Information-Centric Internet of Things: A Distributed Stochastic Optimization Framework

Information-centric networking (ICN) is of high interest to the Internet of Things (IoT) community, since the dissemination of massive data continuously produced by IoT devices can be easily handled by ICN’s data naming scheme and inherent multipath delivery. Providing optimal multipath-oriented transmission control is crucial for ICN-IoT data delivery, but yet remains challenging because of the randomness of request arrival, dynamic link condition, and on-path caching. More prominently, the resource limitation and scalability issues in IoT require the control scheme to be lightweight and distributed. In this paper, we propose a distributed stochastic optimization framework for multipath transmission control in ICN-IoT. The transmission control, including request scheduling and data rate regulation, is formulated as a stochastic concave optimization problem, which aims to accommodate the randomness, unpredictability, and multipath delivery of ICN-IoT and maximize the overall throughput. This problem is linearly separated into two subproblems: 1) a request scheduling problem and 2) a data rate control problem, which can be individually solved per time slot. A distributed alternating descent method (DADM) is designed to optimally control the transmission by solving the aforementioned problems at client sides. DADM enables each client to sequentially update the request schedule and rate regulation via communicating the links and providers they use, which asymptotically converges to optimality while allowing low-complexity and decentralized implementation. Validated by simulations, our DADM significantly improves throughput, delay reduction, and energy efficiency, in comparison with other state-of-the-art solutions.

Efficient Caching for Data-Driven IoT Applications and Fast Content Delivery with Low Latency in ICN

Edge computing is a key paradigm for the various data-intensive Internet of Things (IoT) applications where caching plays a significant role at the edge of the network. This paradigm provides data-intensive services, computational activities, and application services to the proximity devices and end-users for fast content retrieval with a very low response time that fulfills the ultra-low latency goal of the 5G networks. Information-centric networking (ICN) is being acknowledged as an important technology for the fast content retrieval of multimedia content and content-based IoT applications. The main goal of ICN is to change the current location-dependent IP network architecture to location-independent and content-centric network architecture. ICN can fulfill the needs for caching to the vicinity of the edge devices without further storage deployment. In this paper, we propose an architecture for efficient caching at the edge devices for data-intensive IoT applications and a fast content access mechanism based on new clustering and caching procedures in ICN. The proposed cluster-based efficient caching mechanism provides the solution to the problem of the existing hash and on-path caching mechanisms, and the proposed content popularity mechanism increases the content availability at the proximity devices for reducing the content transfer time and packet loss ratio. We also provide the simulation results and mathematical analysis to prove that the proposed mechanism is better than other state-of-the-art caching mechanisms and the overall network efficiencies are increased.

Popularity‐aware back‐tracing partition cooperative cache distribution for space–terrestrial integrated networks

Space-terrestrial integrated networks consisting of low earth orbit (LEO) satellites andterrestrial users are widely developed for potentially diversified requirementsof content distribution. With an obviously time-varying topology, however, designing a distribution strategy faces several explicit challenges, such asprolonged content access latency and significant transmission overheads, due tolack of contact opportunities and limited on-board storage space. In this study, therefore, a novel back-tracing partition directed on-path caching distributionmechanism (BPDM) is proposed for the file distribution in the hybrid LEOconstellation and terrestrial network. In the proposed strategy, a group offeasible on-path cache nodes is iteratively selected by utilising awell-designed cross-timeslot graph, as well as a collaborative cached contentplacement strategy, called as multiple regions cooperative cache algorithm, bycarefully considering diversified popularity of target files. As a result, theproposed BPDM could efficiently reduce redundant transmissions of content accessfor different users by fetching objective file mainly from limited quantities ofintermediate caching nodes. Through the simulation results, the proposed methodcan obviously decrease the holistic overheads and access delay compared with theminimum spanning tree algorithm and Network Central Location (NCL) nodeselection metric.

OpenCache: A lightweight regional cache collaboration approach in hierarchical-named ICN

Information-centric networking (ICN) names contents instead of end-nodes and enables in-network caching to reuse those named packets, thus improving the efficiency of content delivery. On-path caching is an inherent feature in ICN, which caches contents along the path from providers to consumers, while off-path caching is not directly supported and its maintenance normally requires non-trivial overhead. In this paper, we propose a lightweight regional cache collaboration approach, called OpenCache, to sharing popular cached data among small-range caches with least cache information exchanges, especially for hierarchical-named ICN. Different from other available solutions, OpenCache enables collaborators to exchange aggregated hierarchical names (i.e., prefixes), instead of data structures summarized from separated and specific data names, to fundamentally reduce the collaborating cost of communication and maintenance. In addition, our approach exploits forwarding information base (FIB) to selectively relay Interest packets to nearby collaborative routers for low-cost data retrieval. Theoretical analyses and extensive experiments have been conducted to evaluate our scheme and the results show that OpenCache can reduce packet latency in retrieving data by about 38% compared to original ICN while its additional collaborating overhead is only around 15% of other schemes. Our approach explores the feasibility of lightweight collaboration with aggregation of hierarchical names.

Priority-based content processing with Q-routing in information-centric networking (ICN)

With exponential increase in the number of users and available data, service providers are facing hard times to satisfy and improve end user experience. Researchers have come up with the idea of exploiting increasing number of routers in a network, and it leads to the development of information-centric networking (ICN). Efficient usage of the in-network caches and content forwarding methodology are the key issues in an ICN architecture. ICN reduces average hop count and correspondingly average content download delay because the intra-domain routers in ICN have storage capacity and they can act as temporary content provider. In this paper, we address the content management issue in a cache with finite storage capability and propose an efficient content management policy that changes a router to a self-sustained cache. We propose a novel methodology to process content packets in the buffer of a cache and correspondingly reduce the propagation delay through a cache. We simulate our proposed algorithm over real-life network environment and evaluate the performance of different user experience metrics, e.g. average latency, throughput, goodput, and link load. Simulation results suggest that our proposed model outperforms the existing state-of-the-art on-path caching strategies.

A Survey of Caching Policies and Forwarding Mechanisms in Information-Centric Networking

Information-centric networking (ICN), an alternative to the host-centric model of the current Internet infrastructure, focuses on the distribution and retrieval of content instead of the transfer of information between specific endpoints. In order to achieve this, ICN is based on the paradigm of publish-subscribe and the concepts of naming and in-network caching. Current approaches to ICN employ caches within networks to minimize the latency of information retrieval. Content may be distributed either in caches along the delivery path(s), on-path caching or in any cache within a network, off-path caching. While approaches to off-path caching are comparable to traditional approaches for content replication and Web caching, approaches to on-path caching are specific to the ICN area. The purpose of this paper is to provide a review of the caching problem in ICN, with a focus on on-path caching. To this end, a detailed analysis of the existing caching policies and forwarding mechanisms that complement these policies is given. A number of criteria such as the caching model and level of operation and the evaluation parameters used in the evaluation of the existing caching policies are being employed to derive a taxonomy for on-path caching and highlight the trends and evaluation issues in this area. A discussion driven by the advantages and disadvantages of the existing caching policies and the challenges and open questions in on-path caching is finally being held.

An Aggregatable Name-Based Routing for Energy-Efficient Data Sharing in Big Data Era

Big data strongly demands a network infrastructure having the capability to efficiently collect, process, cache, share, and deliver the data, instead of simple transmissions. Such network designs show the requirements of energy efficiency, availability, high performance, and data-aware intelligence. To meet these requirements, we adopt the information-centric networking (ICN) approach, where data are retrieved through names and in-network caching is utilized. However, as the typical existing ICN architectures, content centric network (CCN) cannot efficiently utilize the caches for data sharing because of the on-path caching strategy, and network of information (NetInf) demonstrates the resolution latency for data retrievals. To design an efficient and effective ICN architecture for big data sharing, we combine the strong points of CCN and NetInf, where information islands (IOIs) and management plane are utilized for direct data retrieval and global data discovery, respectively. We provide a reference architecture and propose an aggregatable name-based routing (ANBR), which can naturally enable consumers to retrieve the closest copy of information. In this network, each piece of data can be cached at one IOI at most once, which greatly improves the efficiency of cache usages. The consumers first try to retrieve the data in the local IOI, and then try to globally retrieve it from the closest IOI, holding the copy of the data if necessary. We investigate the impact from the key factor, IOI size, to the energy consumption of ANBR. It shows that energy consumption first decreases and then increases as the IOI size increases, and the optimized IOI size can be found for deployment. Furthermore, we study the relation between the optimized IOI size and the average retrieval times for the data. The result shows that the optimized IOI size increases as the average retrieval times increase.