## 3 Design Overview  
### System Architecture  
According to different name resolution approaches, there are two types of ICN architectures: the ICN architecture based on the name routing approach and the ICN architecture based on the standalone name resolution approach. In an ICN architecture with the standalone Name Mapping and Resolution System (NMRS), the name resolution process is separate from the information routing process, making it more compatible with existing network infrastructure (primarily IP infrastructure). Therefore, the multipath transmission system proposed in this paper is based on the ICN architecture with the standalone NMRS. Identification is an important part of the ICN network architecture. In this paper, a flat naming method is used to identify all network element entities (devices or data chunks) in the ICN network using a unique and unchanged Entity-ID (EID). The mapping relationship between the identifiers of these network element entities and their network address (NA) is managed and maintained through NMRS. Because there are a large number of IP facilities, the IP address is used for NA. Named Data Chunk (NDC) is the basic unit of ICN network data transmission. In the IP-compatible ICN architecture, the size of the data chunk can be set to be greater than 1 MB [33]. During data transmission, the ICN router on the transmission path can cache the forwarded data packets. When an ICN router caches a complete NDC, the NDC will be identified by a unique data chunk EID. After that, the ICN router cached the NDC registered the mapping relationship between the IP of the node and the EID of the NDC to NMRS, becoming a new content source. Consumers obtain the corresponding NDC from the network through the data chunk EID. In order to obtain the NDC, the consumer first queries NMRS for the replica node NA list corresponding to the data chunk EID and selects an optimal replica NA from it. After that, consumers complete the acquisition of the corresponding data chunk by using the NA of the optimal copy. Due to some security reasons, consumer devices usually cannot directly obtain the NA of the nodes in the network from NMRS, so the corresponding work is usually completed by the ICN edge nodes [34]. Compared with IP routers, ICN routers usually have greater flexibility and can better realize the dynamic forwarding of data packets. The ID/NA coordination and reconstruction function integrated into the ICN router can process the address field in the data packet during the data packet forwarding process [30], for example, change the destination address according to the EID query result or remove some of the carried addresses from the address field, and then reconstruct the data packet with the modified address through the data packet reconstruction function to form a new packet, finally forward based on the address forwarding mechanism. The ID/NA coordination and reconstruction function of the ICN router provides convenience for multipath construction. Based on the above description, the ICN architecture with standalone NMRS can effectively support the construction of the multipath transmission system and is compatible with existing IP facilities. Figure 1 shows the structure of MPTS-ICN. MPTS-ICN is mainly composed of three logical entities: edge nodes, multipath service nodes, and standalone NMRS. NMRS and multipath service nodes jointly provide data relay services for users. NMRS is the core component of the MPTS-ICN architecture, which maintains and manages the mapping relationship between the MPSID and the multipath service node NAs. NMRS usually includes the Global Name Mapping and Resolution System (GNMRS) and the Local Name Mapping and Resolution System (LNMRS) [30]. GNMRS is a general global information service system, which is generally deployed in the cloud to ensure the full storage of the whole network identifier-address mapping correlation and the accessibility of content. LNMRS is a distributed autonomous service system based on a hierarchical structure of service levels.