Hea-Sook Park

QoS negotiation for IPTV service using SIP

This paper addresses QoS negotiation algorithm for IPTV services by using SIP. IPTV is defined as multimedia services such as television/video/audio/text/graphics/data delivered over IP based networks managed to provide the required level of QoS/QoE, security, interactivity and reliability by the ITU-T IPTV FG. As stated in its definition, IPTV provides the required level of QoS/QoE. To achieve this, IPTV service frameworks should be able to negotiate QoS/QoE with users or customers and SIP is one of the most proper methods for the SLA negotiation.

IP Geolocation with a Crowd-sourcing Broadband Performance Tool

In this paper, we propose an IP geolocation DB creation method based on a crowd-sourcing Internet broadband performance measurement tagged with locations and present an IP geolocation DB based on 7 years of Internet broadband performance data in Korea. Compared with other commercial IP geolocation DBs, our crowd-sourcing IP geolocation DB shows increased accuracy with fine-grained granularity. We confirm that the low accuracy of commercial IP geolocation DBs mainly results from selecting a single representative location for a large IP block from the Whois registry DB, parsing city names in a naive way, and resolving the wrong geolocation coordinates. We also found that the geographic location of IP blocks has continuously changed but has been stable. Although our IP geolocation DB is limited to Korea, the 32 million broadband performance test records over 7 years provide wide coverage as well as fine-grained accuracy.

Swarm Intelligence Based Self-organizing QoS Framework for Ever-changing Future Networks

We consider a new QoS framework for a wide range of multimedia services in ever-changing networks where traffic is dynamic and network topologies frequently change. In this paper, for such networks, we propose a new self-organizing QoS framework called AntQoS, which is inspired by recent works on ant colony optimization. Compared with previous QoS frameworks, AntQoS provides two quite promising capabilities: 1) the self-organized network QoS (not pre-defined QoS), which autonomously reconfigures itself by promptly adapting to changing network environments such as sudden arrivals of highly bursty traffic, and 2) the self-organized network controls, which autonomously resolve the network congestion and intrinsically resist the multiple network failures. These two promising capabilities enable the proposed AntQoS framework to efficiently and reliably support a wide range of multimedia services with various quality demands. Especially, these capabilities are provided by making use of swarm intelligence of artificial ants without any supervised control. For this purpose, AntQoS employs one single artificial ant colony on an ever-changing network; a number of artificial ants in the employed colony explore network and measure or gather the status information about the networks. Based on the gathered information, AntQoS organizes and maintains a small number of virtual sub colonies named QoS colonies. The QoS colony is an intelligent virtual colony to be capable of searching the path which guarantees the given quality demands of flows. In addition, it is autonomously generated, maintained, and deleted for promptly adapting to the ever-changing network status. Simulation results demonstrate that AntQoS successfully supports various multimedia services with diverse delay requirements while increasing the network throughput by approximately 20% compared to the well-known IntServ frameworks. Simulation results also show that AntQoS autonomously redistributes the congested traffic and resists the unexpected network failures.

A study on bandwidth guarantee method of subscriber based diffserv in access network

In this paper, we describe the structure of the access network and we propose bandwidth guarantee scheme for subscriber and service. The scheme uses two kinds of the classification table, which are called ”service classification table” and ”subscriber classification table.” Using the classification table, we can identify the flow of the subscriber and service. Also, we compute the number of hash table entry to minimize the loss ratio of flows using the M/G/k/k queueing model. Finally, we apply to deficit round robin (DRR) scheduling through virtual queueing per subscriber instead of aggregated class.

A Study on a Bandwidth Guarantee Method of Subscriber-based DiffServ in Access Networks

QoS is an important requirement of the FTTH (Fiber To The Home) subscriber in access network using E-PON (Ethernet Passive Optical Network). In this research, we describe the structure of the access network and propose a bandwidth guarantee scheme for subscriber and service according to the requirements of the subscriber, service and system. This scheme uses two kinds of the classification table, which are called `service classification table` and `subscriber classification table.` Using the classification table, we can identify the flow of the subscriber and service. Also, we compute the number of hash table entry to minimize the loss ratio of flows using the M/G/k/k queueing model. Finally, we apply the DRR scheduling through virtual queueing per subscriber instead of the aggregated class.