The Sixth-generation mobile communication system is expected to serve as a foundation for supporting large-scale connections of IoT devices across various fields, such as smart cities, healthcare, and transportation. Meanwhile, control plane congestion caused by the numerous connection management (CM) procedures for user plane release/re-establishment has emerged as a significant challenge. This paper proposes a novel CM mechanism that loosens the structural coupling between the UE and the U-plane.

Extreme Edge Computing (EEC) leverages nearby resources, such as smartphones and smart IoT devices, to offer reduced latency and enhanced privacy through local data processing. However, the variety of devices and unstable network connections present significant challenges. WebAssembly enables a web-based container platform suitable for EEC; however, it is challenging to host applications continuously on a single node. This paper presents a lightweight solution for migrating Wasm workloads between heterogeneous devices on the platform. Our approach utilizes the Asyncify mechanism to access and preserve the access-restricted CPU and stack states for immediate transfers without altering the web browser or Wasm runtime. Our evaluation shows migration times under 5 milliseconds, an improvement of over 80 times compared to the existing Linux container system, with minimal performance degradation of just 0.4%.

Reliable Moon-Earth communication is essential for long-term human presence on the Moon. Ensuring reliable communication requires careful consideration of various factors, including the choice of communication protocols. For high-latency deep-space links, the Bundle Protocol (BP) is designed to handle disruptions. At the same time, the Artemis program envisions IP-based wireless technologies, such as Wi-Fi and mobile networks, on the lunar surface. However, since these two approaches rely on different protocol stacks, a gateway is needed to bridge IP and BP, allowing end devices to communicate seamlessly without BP awareness. This paper presents a gateway bridging IP and BP networks and evaluates three implementations based on their termination layer. Through emulated Moon-Earth communication experiments, we show that application performance varies significantly with termination layer selection, highlighting the need for mission-specific gateway design.

Sixth-generation (6G) mobile communication systems have been studied to deal with the exponential increase in mobile traffic. Improving the processing load and power consumption will be a challenge for the 6G Radio Access Network (RAN). Simultaneously, RAN virtualization, where the RAN functions are implemented in commodity servers as software, has been developed and commercialized from the viewpoint of reducing cost, scalability, and simplifying operations. Central Processing Units (CPUs) generally execute the virtualized RAN functions. In contrast, hardware offload schemes have been considered, where the implemented GPUs (Graphics Processing Units) and FPGAs (Field Programmable Gate Arrays) run a part of the functions instead of CPUs according to the characteristics of each hardware. For instance, GPU can perform parallel processing faster and more efficiently than CPU, while FPGA can perform routine operations excellently. In addition to these proper selections of execution hardware for each RAN function, we propose an architecture that switches with or without hardware offloading depending on the traffic loads to decrease power consumption. Through experimental evaluation, we measured the energy efficiency of the offloading for each RAN function and overall 5G RAN. Finally, we discuss the threshold of dynamic offloading and estimate the power consumption of a 5G base station from statistical data.

IoT devices are now used in many different fields and applications, and they generate a large amount of traffic when sending sensor data to the cloud for analysis. By offloading these computing tasks to edge computing, the network traffic on the core network and latency can be reduced. However, the resources at the edge are limited, making it difficult to respond to the rapidly expanding number of IoT devices. To solve the problem, extreme edge computing, which utilizes the computing resources of end devices for task offloading, is emerging. The conventional task execution methods in edge computing are unsuitable for extreme edge computing because of the nonuniformity of end devices and connectivity. To meet the requirements of extreme edge computing, we propose a novel WebAssembly container system that is portable, lightweight, and manageable. Our proposed system has two types of container engines working as native applications and Web applications. This enables the execution of general-purpose computing tasks on various devices with different CPU architectures and OSs. We evaluate our prototype implementation working on these devices to confirm the benefits and effects of our proposed system for extreme edge computing.

This paper proposes an architecture and route control scheme of the layer 1 repeater-based IAB system, which can expand a high-frequency radio access area with high-quality communication service. Although repeaters just amplify and retransmit radio signals, the proposed system enables building a multi-hop network using beamforming and scanning. It introduces an external route control server to calculate the route tree under the limited hop count requirement and minimize the total route tree cost. This paper also shows its effectiveness through simulations using the NetworkX package.

In Named Data Networking (NDN), consumers can retrieve content from anywhere in the network, including from the server and routers' cache. Therefore, the Round-Trip Time (RTT) of packets can vary when downloading content in NDN compared to TCP, which establishes a session between a client and a specific server. The current transport layer protocol of NDN is mainly designed with reference to TCP. Its timer-based loss detection is not well designed for the nature of NDN, where the RTT of each packet can vary significantly, and leads to false loss detection. In this paper, we attempt to revisit the loss detection mechanism in NDN. We clarify the potential performance degradation of NDN due to the spurious timeouts and propose an NDN-PTO mechanism that improves the accuracy of loss detection by identifying spurious timeouts with a probe Interest. We evaluate the performance of NDN-PTO through a comprehensive simulation and describe its benefits.

The Locator/ID Separation Protocol (LISP) is being standardized in IETF, which separates the IP address functionality into routing locators (RLOC) and endpoint identifiers (EID). LISP is applicable for instant Virtual Private Network (VPN) services because it has IP tunneling features. However, there are two main issues with application to VPN. One is a Map server/Map resolver (MS/MR) basically allows any third party to know a mapping table even if it is irrelevant to the VPN. The other is an MS/MR should identify the VPN to which the requested site belongs because the requested EIDs can be private addresses and may overlap with other VPN sites. A simple solution is to deploy an independent MS/MR for every VPN. However, this is undesirable from a cost perspective. We present a new LISP-MS/MR that provides a large number of VPN services using a single set. This MS/MR creates a logically separated EID-to-RLOC mapping table for each VPN and selects an appropriate type according to the requesting VPN site. To ensure this, our scheme uses Authentication data included in the Map register for an initial VPN identification of the registering site and associates the identified VPN ID with the registered RLOC. In following Map requests, the appropriate mapping table for the requesting VPN site is selected based on its RLOC. We confirmed the basic network functions of VPN using the prototype system. The results of scalability tests show that our MS/MR completes the transaction for nearly-simultaneous 10,000 Map registers or requests within three seconds.

Recently, it has been necessary to perform traffic sampling in order to deteriorate the load of capturing and analyzing processes, as the amount of ISP traffic grows. Packet sampling and flow sampling are main sampling techniques. In order to estimate flow size distribution from sampled data, each sampling method has its own advantages and disadvantages. Flow sampling can extract flows in proportion to the original flow size distribution but is difficult to extract large-sized flows due to the heavy-tailed flow size distribution. On the other hand, packet sampling can extract large-sized flows but complete flows cannot be extracted. In this paper, we propose a hybrid sampling method which performs both flow sampling and packet sampling in parallel to utilize both advantages of above two methods and improve estimation accuracy. We also propose cost-effective implementation which employs a general-purpose switch. By verifying with real traffic data, we confirmed the effectiveness of our proposed method in terms of reproducibility.

The growth of the Internet has facilitated data collection on a large scale. In Internet research using questionnaires, privacy is an important issue. To ensure privacy, we propose an answering method using probability conversion for Internet research. In this paper, we develop noval evaluated value, anonymity. And from the evaluation of two conversion functions, the applicable scope of the proposed method is clarified.

This paper proposes a novel approach for improving channel zapping delay on IPTV broadcasting services. Channel zapping delay is a crucial issue for digital TV broadcasting, which entails audio/video data buffering before reproduction. Such delay could be mitigated in an IP environment if a receiver accelerated this buffering using additional burst transmissions from dedicated servers when a channel zap occurs. However, most conventional solutions are based on the unicast burst, which may cause an impulsive server/network load because channel zaps tend to happen simultaneously when programs are finished or suspended by commercial messages. To reduce this load, we propose a new multicast-based solution that takes into consideration the timing variation in channel zap on each receiver. We have confirmed a maximum 1-second reduction in the zapping delay using commercial multicast streams.