Insufficient Offset Time Research Articles

Analysis of impact of control-plane on an efficient switching paradigm: OBS of IP/WDM networks

In high speed optical burst switched (OBS) networks two parallel networks, namely a data and a control network (plane), suffers from contention, insufficient offset-time, average burst length and scheduling operations causing excessive delay in processing of control packets in an electronic core-node controller, thus as a result incur higher blocking probability, inefficient bandwidth utilization, etc. In this paper, to address this, we provide an analytical modeling, detailed analysis of control plane and its impact on OBS performance. Based on above, we select optimal performance oriented parameters such as average burst length, sufficient offset-time duration and scheduling and reservation operations in order to show that the impact of control-plane is negligible (as compared to data-plane) on OBS based system performance.

Analysis of Impact of Control Plane on High Speed Switching Paradigm

Optical burst switching (OBS) network is viewed as two parallel networks, namely a data and a control network (plane). In this paper, the main focus has been given only on the impact of control-plane on performance of OBS. In high speed networks, several factors such as contention, insufficient offset-time, average burst length and scheduling operations may cause excessive delay in processing of control packets in an electronic core-node controller, thus as a result incur higher blocking probability, inefficient bandwidth utilization etc. In this paper, to address this, an analytical modeling, detailed analysis of control plane and its impact on OBS performance has been provided. Based on above, optimal performance oriented parameters can be selected such as average burst length, sufficient offset-time duration and scheduling and reservation operations in order to show the impact of control-plane negligible (as compared to data-plane) on OBS based system performance.

Modeling the Impact of Control Plane Losses on the Performance of Optical Burst Switched Core Node

The performance of a core node in optical burst switched networks is usually assumed to be limited by the losses in the data plane. We investigate the significance of losses in the control plane due to insufficient offset time and evaluate their contribution in the overall loss probability. We model the control plane with an M/M/1 queue with reneging to evaluate the loss of Burst Header Packets (BHPs) due to insufficient offset time as the load increases. We propose a method to estimate the offset time with variable queueing and processing times and investigate the effect of the control plane parameters on the burst loss probability using both analytical and simulation studies.

Offset Time Configuration in Optical Burst Switching Ring Network

In this paper, a detailed burst header packet (BHP) processing model is presented to characterize the BHP processing time at the switch control unit of optical burst switching ring network. The distribution function of the total BHP processing delay, which is used to configure offset time, is derived based on the proposed model by using central limit, large deviation, and phase-type distribution theorem-based methods, respectively. A simulation platform that takes the practical processing delay of BHP into consideration is developed to evaluate the efficiency of the proposed model and mechanisms. Different distribution function-based offset time configuration mechanisms are analyzed and compared with the fixed offset time configuration mechanism in terms of burst loss ratio for insufficient offset time and average offset time deviation. The results show the validity of our model.

Controlled loops for quality-of-service differentiation in delay-sensitive optical burst switching networks

A novel quality-of-service (QoS) differentiation framework for optical burst switching networks is introduced. Two different methods are provided and subsequently validated. Particularly, both methods aim at using controlled loops as deflection routes, which assures an upper bounded number of hops from source to destination. This yields a 2-fold outcome. First, the insufficient offset time problematic of standard deflection routing under just-enough-time is solved. Second, excessively long delays owing to uncontrolled deflections are avoided. In both methods, the number of allowed loops is proposed as a QoS metric, giving support for class differentiation. This applies to a scenario with heterogeneous traffic demands, each one with different latency and burst loss requirements. The benefits of each proposal are quantified and further compared with existent alternatives by simulations.