تجزیه و تحلیل عملکرد از مدل چند احتمالی خروجی در یک ترافیک چند کلاسه اولویت بندی شده شبکه OBS موجود

Optical burst switching (OBS) is a novel optical switching paradigm which could exploit the huge bandwidth of Dense Wavelength Division Multiplexing (DWDM) technology, and it is a typification of next generation full-optical switching technology. In this paper, the performance of multi-probability outputted model in a priorities traffic existed OBS network has been proposed and analyzed. Based on our proposed scheduling mechanism, the quality-of-service (QoS) of the OBS network has been supported.

Along with the explosive increment traffic in Internet, high-speed and ultra-broadband optical networks have been regarded as the solution for next generation communications. Nowadays, the transmission rate of single-wavelength optical channel in one fiber can reach hundred T level in backbone. But in core switching nodes, due to the lack of optical-memory and optical-logic, the “Electronic Bottleneck” problem still exists. Optical burst switching (OBS) is a novel optical switching technology that connects optical circuit switching to optical packet switching. It is the best solution for “Electronic Bottleneck” recently, and it has been regarded as a next generation IP over WDM optical transport networks [1], [2] and [3]. A typical OBS network is composed of edge nodes, core nodes and WDM links. Edge nodes aggregate and encapsulate IP packets into optical data bursts based on their attributes, including destinations, priorities, etc., and at the same time, edge nodes create burst control packets (BCP) for each corresponding data burst. Core nodes as intermediate sites take charge of BCP process and data burst switching/forwarding full-optically. Under one-way reservation protocols, such as Just-Enough-Time (JET) [4], [5] and [6], a BCP and its corresponding data burst apply an “out-of-band” signaling model to pass through the OBS core network. In the core node blocking system of an OBS network, bursts may use large probability to select the output-port that has the short distance to a given destination, while may use small probability to select the output-port that has the long distance to the same destination. Such burst-outputted model has been proposed in some previous works, which has been called “Multi-Probability Outputted Model (MPOM)” [7] and [8]. The main benefit of MPOM is that, it can make the core node operating at a status more fit for the real networks operational scenario. In this paper, the performance of prioritized multi-classes traffic based MPOM in an OBS core node has been analyzed. High-classes data traffic protection mechanism has been established to support the QoS for the OBS network.

In this paper, the performances of MPOM in a multi-classes existed OBS network have been analyzed. The burst blocking probability, system through capacities, system occupied expectation value and system efficiency have been given and discussed. Results indicate that the performances of MPOM are different from that of the previous output models. The variability of output-port selected probability will cause the alteration for all performances. Our proposed scheduling mechanism for multi-classes traffic can support QoS for the OBS network efficiently.