Input/output (I/O) devices such as a graphics processing unit and a solid-state drive are inserted into I/O slots of a host in data center platforms. With this sort of configuration the I/O devices are used exclusively by the host with resultant inefficient resource usage. In addition, the maximum number of I/O devices that can be assigned to each host is limited by the number of its I/O slots. This paper proposes a method to solve the resource usage inefficiency and assignment limitation by disaggregating I/O devices from hosts. An I/O device accommodated in a device pool is interconnected with multiple hosts by a standard Ethernet and can be flexibly assigned to one of them. Introducing assignment flexibility of I/O devices among hosts improves the resource usage efficiency and enables as many I/O devices as desired being assigned to each host. The authors further propose a method that enables an I/O device to be simultaneously shared among multiple hosts and multiple I/O packets to be aggregated into an Ethernet frame to suppress the performance overhead of the device disaggregation. Evaluation results showed that I/O devices that are compliant to PCI Express are shared with the overhead up to 27 percent.

Presents a conference poster that covers the following topics: bridge chip; PCIe switch; Ethernet; seamless disaggregated computer; and data center.

We propose a method for multilayer in-service reconfiguration for network computing systems that minimizes the total service downtime. Although both software and hardware virtualization technologies has been proposed for dynamic reconfiguration, each one is currently designed to be executed independently and thus their cooperative operations that dynamically reconfigure both of them have not been well-considered. We have developed a method for multilayer in-service reconfiguration that comprises Ethernet-based distributed device reconfiguration (hardware layer), fine-granular I/O service continuity management (software layer), and their orchestration. Application to the management of a session initiation protocol server system built on distributed resources demonstrated that this method achieves dynamic load balancing in response to call rate increases without any failed calls.

This paper presents an overview of global open Ethernet (GOE) architecture as a cost-effective Ethernet-based virtual private network (VPN) solution, and discusses a hardware and software implementation of a prototype system. Three main approaches have been proposed for a VPN solution on metro-area network: resilient packet ring, Ethernet over multiprotocol label switching (EoMPLS), virtual bridged local area network-tag stacking (Q-in-Q). None of these schemes can satisfy the following requirements at the same time: network topology flexibility, affordable network functionalities, low equipment cost, and low operational cost. The proposed GOE system is designed to solve VPN management problems of these approaches with MPLS VPN functionality at a low cost of Ethernet-based solution. The key components of GOE are: 1) a novel GOE tag for high-speed switching and 2) a novel routing and protection module via per-destination multiple rapid spanning tree protocol (PD-MRSTP). Via the analytical performance evaluation of EoMPLS, Q-in-Q, and GOE, we show that the memory cost and the network utilization of GOE is two-three times smaller and 22% higher than the other approaches, respectively. We also have developed a GOE prototype system and obtained the following remarkable hardware and software performance results. The GOE core switch delivered 100% of theoretical maximum throughput (10 G) with zero packet loss even with the field programmable gate array platform, and its 10-G port density is 1.5 times denser than the best currently available products. The GOE switch using PD-MRSTP also delivered a significantly fast protection switching time (1.975 ms), which was significantly faster than legacy Ethernet switches. These performance evaluation results prove that the proposed GOE system can be used as a cost-effective high-performance Ethernet-based VPN solution.