Seunghyun Yoon

Wise : traffic engineering server for a large-scale MPLS-based IP network

As the Internet evolves quickly from a best-effort network to a critical communications infrastructure that requires a higher level of controllability and guarantee of service quality, and the delivery of such communications services becomes even more competitive, large-scale NSPs or ISPs have to focus more on the performance and efficient resource utilization of their networks. This situation naturally leads the providers to seek possible solutions from traffic engineering (TE) methodology. We propose a TE server for a large-scale MPLS-based IP network which addresses TE requirements, such as the measurement, characterization, modeling and control of Internet traffic.

End-to-end flow monitoring with IPFIX

End-to-End (E2E) flow monitoring is useful for observing performance of networks such as throughput, jitter and delay. Typically, E2E flow monitoring is carried out at end hosts with known tools such as iperf. However, the end-host approach may not be easily deployed in a large-scale network because of high cost and administrative overhead. Therefore, in this paper, we propose a new E2E flow monitoring method based on IP Flow Information eXport (IPFIX) that could provide QoS metrics such as throughput, retransmission rate, delay, and jitter for TCP flows and SIP-signalled RTP flows. We have extended the IPFIX templates for carrying QoS-related fields, and developed the E2E flow monitoring function with the open source that could be embedded into routers. From experiments, it was shown that the performance of TCP and RTP flows could be easily examined with the IPFIX-based approach.

Service platform and monitoring architecture for network function virtualization (NFV)

With the advent of cloud and virtualization technologies and the integration of various computer communication technologies, today’s computing environments can provide virtualized high quality services. The network traffic has also continuously increased with remarkable growth. Software defined networking/network function virtualization (SDN/NFV) enhancing the infrastructure agility, thus network operators and service providers are able to program their own network functions on vendor independent hardware substrate. However, in order for the SDN/NFV to realize a profit, it must provide a new resource sharing and monitoring procedures among the regionally distributed and virtualized computers. In this paper, we proposes a NFV monitoring architecture based practical measuring framework for network performance measurement. We also proposes a end-to-end connectivity support platform across a whole SDN/NFV networks has not been fully addressed.

An evaluation of federated cloud computing effect with service level

In this paper, we consider a federated cloud computing effect. Cloud computing provides software, platform, and infrastructure as services. Customers pay for the services in a pay-as-you-go model. As an effort of quantifying the effect of cloud computing, this paper evaluates a federated cloud computing network. For the evaluation we studied the simple deterministic demand model and the simple probabilistic demand model. In both cases, the effects of online migration of virtual machines can be clearly identified. Specially, for the probabilistic model we define service level as the proportion of time that the capacity of a data center satisfies the amount of the demand. With the service level concept, the performance of the federation and non-federation can be compared. The models in the paper are basic quantitative ones which can be extended to several other complex models with financial effects.

Implementation of inter-domain path computation element

The Path Computation Element (PCE) Working Group (WG) at the Internet Engineering Task Force (IETF) is chartered to specify a PCE-based architecture for the path computation of inter-domain MPLS/GMPLS-based traffic engineered Label Switched Paths (LSPs). The PCE architecture introduces a special computational entity that will corporate with similar entities to compute the best possible path through single or multiple domains. This paper presents the state-of-the-art in PCE and several topics (e.g. PCE discovery mechanism, inter-domain path computation). In this paper, we describe the details about our PCE implementation.

Design and Implementation of Traffic Engineering Server for a Large-Scale MPLS-Based IP Network

As the Internet is quickly evolving from best-effort networks to a very critical communications infrastructure that requires higher quality Internet services and the delivery of such communications services become competitive, large-scale NSPs or ISPs have to concern much more on the performance and efficient resource usages of their networks. This situation naturally leads the providers to seek a possible solution from traffic engineering (TE) methodologies. In this paper, we propose a TE server solution for a large-scale MPLS-based IP autonomous system, which addresses these TE requirements such as the measurement, characterization, modeling and control of Internet traffic.

Extending tenant networks across geographically distributed clouds.

Recently the inter cloud networking becomes a big issue because cloud service providers build and use tens of geographically distributed clouds. Many virtual infrastructure services and applications can be deployed across them, so providing multi-tenant virtual networks which span distributed clouds becomes a crucial extension to the cloud networking. In this paper, we present several technologies to extend per tenant virtual networks across geographically distributed multiple clouds, and then examine their characteristics to be utilized.

Routing information collector for Path Computation Element

In this paper, we present the design and the implementation of OSPF-TE routing information collector for MPLS and GMPLS networks. OSPF is commonly used as an IGP in MPLS and GMPLS networks to determine the topology over which LSPs can be established. TE extensions have been recently enabled in OSPF to support SPF tree calculation upon different purposes, thus possibly achieving optimal path computation and helping improve resource utilization efficiency. The IETF has standardized the PCE-based architecture, a good candidate to perform multidomain path computation. In such an architecture, the PCE needs the TED to compute the paths requested by a PCC. In this paper, we explain the approaches of using a OSPF-TE for the building and maintenance of the TED.