# A Multipath Data-Scheduling Strategy Based on Path Correlation for Information-Centric Networking
## 1 Introduction  
Since its birth, the Internet has become one of the most important ways for users to obtain information resources. In the past decade, a series of highly significant innovations and reforms have taken place in communication technology and network infrastructure. With the emergence of new network applications and services such as the industrial Internet, big data, artificial intelligence, blockchain, virtual reality, etc., Internet users and traffic have also experienced explosive growth. Information sharing has become the main function and goal of the Internet, and the usage mode of the Internet has gradually evolved toward content access and information acquisition. Users no longer pay attention to the location of the content but to the content itself, as well as the speed, quality, and security of content retrieval and transmission. The traditional host-oriented communication mode is not able to effectively meet the current content-centric requirements and is unable to provide efficient content distribution services. In order to solve this problem, researchers propose to establish overlay networks through patching at the application layer to enhance content distribution capabilities such as Content Delivery Networks (CDN) and Peer-to-Peer (P2P) [1]. Although this patch-based method alleviates the pressure of content demand expansion to some extent, its superimposed improvement leads to problems of low network resource utilization and high complexity. In this context, the Information-Centric Networking (ICN) is proposed, which shifts the communication mode from host-centric to information-centric, completely changing theretrieval and transmission of content [2]. Since its proposal, ICN has attracted the attention of many research institutions and individuals. Different from existing TCP/IP networks, the content identifiers (ID) and locators are separated in ICN. According to the difference between addressing and routing methods, the existing ICN architecture can be divided into two types. The first is the ICN paradigm of name-based routing, such as Content Centric Networking (CCN) [3], Named Data Networking (NDN) [4; 5], and Publish-Subscribe Internet Technology (PURSUIT) [6], which use hierarchical and aggregable names, and their addressing and routing are coupled. However, this type of ICN paradigm cannot take advantage of existing IP infrastructure, resulting in high deployment costs. The latter is the ICN paradigm of stand-alone name resolution, such as MobilityFirst [7], Network of Information (NetInf) [8] and on-Site, Elastic, Autonomous Network (SEANet) [9], which use flat and non-semantic names and are decoupled in terms of addressing and routing. This type of ICN paradigm is compatible with existing IP networks, thus greatly reducing deployment costs. The multipath transmission scheduling strategy proposed in this paper is also applied in the latter ICN paradigm. The ICN paradigm of stand-alone name resolution uses ID-based naming and addressing, enhancing the addressing space and diversity. However, due to compatibility with IP networks, the ICN packets are still transmitted along the default path provided by the IP routing protocol. With the increase in network traffic, the congestion probability of the default path will increase, and the end-to-end throughput will decrease. This mismatch between addressing and routing limits the transmission quality of ICN. In order to improve the transmission efficiency and robustness, researchers have proposed various multipath transmission methods. At the network layer, Equal-Cost Multi-Path (ECMP) [10] is a classic multipath routing protocol which is widely used in Data Center Networks (DCNs). However, the equal traffic distribution makes ECMP difficult to adapt to asymmetric links. Segment routing [11] encodes the transmission path in the packet header, making the transmission path definable. Particularly when it is used with software-defined networking (SDN), the performance of segment routing has been effectively improved [12].