Hongkyu Jeong

IEEE 802.1 AVB and Its Application in Carrier-Grade Ethernet [Standards Topics]

Ethernet is increasingly being used in carrier networks to transport real-time traffic, including wireless backhaul network traffic, time-sensitive audio/video applications in access networks, and circuit emulation for legacy services. With the replacement of traditional circuit-switched networks with Ethernet-based packet networks, it must be ensured that the application timing and QoS requirements are met. The IEEE 802.1 Audio/Video Bridging Task Group is developing a comprehensive set of standards to enable high quality, low-latency streaming of time-sensitive applications. These standards specify a means of providing time synchronization (IEEE 802.IAS), a resource reservation protocol (IEEE 802.1Qat), and a set of forwarding and queuing rules that bound the variability of delay in an AVB network (IEEE 802.1Qav). These standards are described, including their potential application to carrier-grade Ethernet networks.

A tree-based slot allocation algorithm for loss-free slotted OBS networks

Optical burst switching (OBS) is regarded as one of the most promising switching technologies for next generation optical networks. However, the data burst contention problem is still unresolved thoroughly even though slotted OBS (SOBS) is studied as a new paradigm reducing the blocking rate. In this article, we propose a tree-based slot allocation (TSA) algorithm for loss-free SOBS networks, where the TSA algorithm originally avoids contention of the time-slots by reserving the time-slots with different time-slot positions for the source nodes, respectively. In order to manage the time-slots efficiently, we also propose an OBS superframe, which is a cyclic period and consists of multiple time-slots transmitted by the source nodes toward the same incoming port of a destination node. In addition, we attempt to optimize multiplexing of the OBS superframes to reduce wavelength consumption. On the other hand, when incoming traffic is beyond expectation, a source node may need more time-slots to prevent packet loss because of buffer overflow. For reallocation of the time-slots, we propose a flow control scheme managing some number of shared time-slots, where a control node adaptively allocates (or redeems) the time-slots to (or from) source nodes by utilizing the shared time-slots based on fluctuating traffic condition. Simulation results show that the blocking rate of the proposed TSA–OBS scheme is zero with acceptable queueing delay at moderate traffic offered loads. In addition, multiplexing optimization simulated in the 14-node NSFNET achieves a 63% reduction of wavelength consumption. Moreover, the proposed flow control scheme assisting the TSA algorithm maintains a target upper-bound of queueing delay at the source node, so that packet loss caused by buffer overflow is prevented.

Effect of flow aggregation on the maximum end-to-end delay

We investigate the effect of flow aggregation on the end-to-end delay in large scale networks. We show that networks with Differentiated services (DiffServ) architectures, where packets are treated according to the class they belong, can guarantee the end-to-end delay for packets of the highest priority class, which are queued and scheduled with a strict priority, but without preemption. We then analyze the network with arbitrary flow aggregation and deaggregation, and again derive an upper bound on the end-to-end delay. Throughout the paper we use Latency-Rate (

Instant service policy and its application to deficit round robin

{\mathcal{LR}}

Performance analysis of the extra offset-time based QoS mechanism in TCP over optical burst switching networks

) server model, and prove that FIFO, Strict Priority, and other rate-guaranteeing servers with aggregated flows are all

Loss-Free Slotted OBS for Ring and Mesh Hybrid Networks

{\mathcal{LR}}

A data profile-based contention-free MAC protocol for the patient monitoring systems on WBANs

servers to individual flows in certain conditions. We show that the delay bound of a flow that experiences aggregation and deaggregation, including the flows in DiffServ, depends on, among others, the burst sizes of the other flows within the aggregated flow and the number of the aggregations and the deaggregations.

Suppressing Maximum Burst Size Throughout the Path with Non-work Conserving Schedulers

Many of scheduling algorithms that provide a predefined bandwidth to a traffic flow fall into a category of Latency-rate (

The Impact of Burst-Switching Paradigm on Transport Protocols

\mathcal{LR}

Method and apparatus for determining handover in mobile communication system

) server. A series of