Eiichi Horiuchi

Performance evaluation of the simplified WFQ to multiplex a huge number of queues

Weighted Fair Queuing (WFQ) is a packet scheduling technique allowing guaranteed bandwidth services. However, it is very difficult to implement the WFQ for a lot of queues, because the amount of required calculations for WFQ is proportional to the number of queues. Therefore we proposed the simplified WFQ (SWFQ) mechanism which can support a huge number of queues with guaranteeing the provisioned bandwidth for each queue while it requires fewer amounts of calculations by using approximation techniques. To compare the details of SWFQ and WFQ, a series of simulations are conducted. The result of the simulation shows that SWFQ can guarantee the bandwidth for each queue as same as WFQ and also shows that the difference between WFQ and SWFQ can be negligible when the granularity of the quantization for an approximation is sufficiently fine. In conclusion, these results clarify that SWFQ is an effective mechanism which can provide the same characteristics as WFQ.

A GMPLS-based path establishment experiment with tunable dispersion compensation over in-field fibers

This paper reports an experiment over in-field fibers applying GMPLS (Generalized Multi-Protocol Label Switching)-based control for automatic discovery of chromatic dispersion and wavelength path establishment with tunable dispersion compensation. Two wavelength paths were successfully established with error-free data transmission.

Design of a chromatic dispersion measurement control protocol based upon the GMPLS architecture

This paper analyzes requirements of measurement control for chromatic dispersion based upon GMPLS and defines an abstract control protocol applicable to both link and path measurements. The protocols LMP application has successfully demonstrated measurement control.

A proposal of a new packet scheduling algorithm which can reduce the delay of small packets

Eligibility Based Round Robin (EBRR) scheduler proposed by Lenzini et al. is a packet scheduling algorithm which can be considered as an extension of Surplus Round Robin (SRR), computational complexity of which is O(1) even when quantum size is less than the maximum packet size. In this paper, we propose an extension of EBRR which makes it possible to transmit packets smaller than a threshold prior to packets larger than the threshold among packets received in one scheduling round. It can be used in Home Gateway. The computational complexity of the proposed algorithm is O(1).

Impairment compensation control for wavelength switched optical networks (WSON)

For automatically switched dynamic wavelength paths meeting traffic demands of metro/core networks, precise determination of physical impairments over such paths and appropriate configuration of their compensation capabilities are required. This paper discusses control protocol for impairment measurement and compensation configuration for wavelength paths based on the IETFs WSON standardization efforts.

A study on application-aware QoS control in OSGi based home gateway

To improve response time of time-sensitive application in a network using low speed communication link, implementation design of a middleware bundle adjusting bandwidth between applications is proposed and performance of the design is experimentally evaluated. The experiment shows that worst case delay of a high-priority packet is reduced from 4230 ms to 218 ms.

A study on application-aware power-saving control method for sensor stations in home gateway

In recent years, home ICT services have been actively proposed. To realize the services, power consumption of sensor station increases when a sensor station often wakes up to report sensor data. In this paper, we proposed an application-aware power-saving control method for sensor stations and confirmed an effect of a proposed method which is constructed as OSGi bundle in HGW. By using the proposed method, it is possible to extend a reporting period of sensor station to a requesting period of service providing server. And a timing difference between reception of sensor data and reception of request from the server in HGW can be reduced to 49 msec in the evaluation.

Fault recovery with routing and adaptation control of chromatic dispersion

We propose mechanisms of routing and adaptation control of chromatic dispersion to enable fast recovery in various fault recovery schemes for all-optical networks. A link protection with routing based on chromatic dispersion errors is proposed and evaluated.

Design and implementation of Chromatic Dispersion control protocol

We propose and demonstrate a control protocol of automatic measurement of Chromatic Dispersion (CD) for compensation on dynamic all-optical paths. The control protocol reduces operational cost and time to establish paths with sufficient quality.

A proposal and evaluation of multi-class optical path protection scheme for reliable computing

Emerging GMPLS (Generalized Multi-Protocol Label Switching)-based photonic networks are expected to realize dynamic allocation of network resources for high-performance computing. To address diverse reliability requirements of computing, various optical path recovery schemes, some of them under GMPLS standardization, should be supported on a photonic network. This paper proposes multi-class optical path protection scheme, supporting 1+1 protection, M:N protection, and extra path reusing back-up resources, for a unified approach to build such a network. The proposed scheme was implemented on an OXC prototype and its path establishment time and failure recovery time were evaluated. It was confirmed that a node supporting a wide range of recovery capabilities could realize small or relatively small recovery time to various applications according to their diverse reliability requirements.