Janaka Wijekoon

Modeling of Router-based Request Redirection for Content Distribution Network

The increase of digital data between content’s servers and clients in a network causes congestion problems when downloading big web contents including files, streaming media, etc. The problem becomes pronounced when a narrow bandwidth or unexpected termination of streaming services is appeared. Content Delivery Network (CDN) is introduced to overcome such problems by redirect client’s request to the best server which proximal and least loaded. However, with intensity increase of people accessing a particular content, the performance of CDN is reduced and sometimes congested. We propose an architecture to solve such problems with a new method to redirect client’s request through a special router called Service-oriented Router (SoR). In this paper, several analytical studies and experiments have been conducted and the result show that router-based redirection is more effective than DNS-based redirection that is currently being used. SoR has been introduces as a content-based router and has capability to do deep packet inspection (DPI) into the packet streams and analyze them. We use SoR in our proposed method as a CDN’s core-router to redirect client’s request to the best server. Our experiment conducted with model and numerical analytic supported by optimal redirection probability based on delay between router and server. The experiment result confirmed that the router-based redirection reduced the response time by 23.3% compared to the DNSbased redirection.

A router-based management system for prediction of network congestion

Network Management System (NMS) plays an important role in networks to maintain the best performance of a network. It employs variety of tools, applications, and devices in order to support network administrators to monitor and maintain the stability of a network. Fault management is part where the NMS dealing with problems and failures, such as congestion, in the network. Generally, most NMSs use Simple Network Management Protocol (SNMP) to monitor and map network availability, performance, and error rates. In the existing NMS process, an SNMP agent is deployed to get information about the network condition and then send them to the administrator for taking further action on solving the problems. However, deploying such agent to the network may increase the traffic density. On the other hand, packet latency and RTT will increase as well. In this paper, we implemented a prototype of the proposing novel system that no need to deploy such agent to obtain network information. Our system analyze the streaming traffic by implementing a Service-oriented Router (SoR). Our objective is to predict a congestion in the specific link in the network through a router-based data traffic analysis using a Bayesian network model. The purpose of the prediction is to support the network administrator to notify the early warning regarding to the fault in the network as long as possible before it actually happening. By this prediction, the network administrator can immediately taking action to avoid the problems.We provided simulation experiment to demonstrate the performance of the proposed system. Our simulation results show that the proposed system can predict a congestion link caused by a particular problem, before hand it is getting congested.

SoR based request routing for future CDN

Internet users are constantly demanding faster and higher quality services from their internet service providers. This results an increase in broadband services, and access to delivery of applications enriched in data become top priority. Therefore, for fast delivery of such applications, Content Delivery Networks (CDNs) have been introduced. The Internet has become a massive system consisting of enormous amounts of information. To maintain the rich information in the Internet and to achieve maximum benefit from networks, Service-oriented Routers (SoRs) have been introduced. A SoR has a high-throughput database and is able to analyze all transactions on its interfaces. In addition, SoRs can provide APIs for accessing stored contents in order to enrich services. CDNs generally use Request Routing (RR) methods to achieve low user latency by performing load balancing among servers. RR is accomplished by selecting the nearest server for a particular user. In this paper we implement a new RR infrastructure that is based on the content of packet streams. The proposed system is independent of DNS-based RR, which is the predominant RR method used by current CDN infrastructures. In our system, content-centric request re-routing with SoR is used. Experimental evaluation and comparison of the round trip time (RTT) result of our proposed system with DNS-based RR indicates that our system achieves 50-60% reduction in connection initiation time. The SoR based RR method is able to reroute packets without disturbing clients, which is not possible using existing RR methods. This feature will make future CDNs more effective and convenient.

Per-hop data encryption protocol for transmitting data securely over public networks

Abstract It is a well-known fact that the Internet traffic travels through public networks. These networks lack security and are vulnerable. Encryption and public key cryptography are important technologies that are used to preserve data security and integrity, and to reduce information theft on the public networks. However, the existing routing protocols are incapable of providing secure data transmission on public networks. To this end, our laboratory introduced the Service-oriented Router (SoR) to maintain rich information for the next-generation networks by shifting the current Internet infrastructure to an information-based and an open-innovation platform. An SoR can analyze all packet stream transactions on its interfaces and store them in high throughput databases. Using the features of the SoR, in this paper, we propose a hop-by-hop routing protocol that provides per-hop data encryption. This infrastructure is proposing to preserve both the security and the privacy of data that traverses through public networks. We implemented a prototype of per-hop data encryption protocol on the ns-3 simulator and the results obtained are discussed in this paper.

Service-Oriented Router-Based CDN System: An SoR-Based CDN Infrastructure Implementation on a Real Network Environment

Internet users are constantly demanding faster and higher quality services from their internet service providers. Therefore, for fast data delivery of such applications, Content Delivery Networks (CDNs) have been introduced. Most CDN providers use Domain Name Resolution (DNS) based request routing (RR) methods to find the nearest server for a particular client and it has both advantages and disadvantages. Importantly, disadvantages result high latencies of data delivery and network congestions. To maintain rich information in the Internet and to shift the current Internet infrastructure to an information-based open environment platform, Service-oriented Routers (SoRs) have been introduced. An SoR has a high-throughput database and it is able to analyze all transactions on its interfaces. Therefore, we have used the basic functionalities of the SoR to diminish disadvantages of the DNS-based RR methods. Proposed system is independent from DNS-based RR and we have conducted experiments based on content-centric RR using the SoR basic functionalities and successfully evaluated and compared both of the round trip time (RTT) and the packet inter arrival time. Our results indicated that SoR-based method can reduce upto 40-50% latency in both connection initiation time and content migration time in-between servers.

Introducing a distance vector routing protocol for ns-3 simulator

In network research, network simulators have been shown to be useful for testing and changing network protocols by means of a controlled manner. As an Internet systems simulator, ns-3 simulator provides an ideal simulation environment for network research. However, ns-3 is lack of table-driven IPv4 routing modules. Despite the fact that a routing protocol is a mandatory component of a network, it is necessary to introduce a table-driven routing protocol for the ns-3 which is able to maintain the network connectivity and consistency. To this end, we introduce a distance vector IPv4 wired routing protocol for the ns-3 simulator (DVRP). The proposing protocol is developed as a table-driven wired routing protocol. In this study, we describe the proposing routing protocol, including its design, implementation, behavior on networks, and limitations.

SLRouting: Server Link Router state Routing Protocol Design and Implementation

Packet propagation delay reduction is becoming the primary concern of the Internet. Internet service providers (ISPs) attempt to optimize packet routing to offer the best route to their subscribers by achieving desired network performance. Consequently, a route computation metric that uses packet propagation delay instead of link state will be a strong incentive for ISP routing optimization, in which case ISPs could ensure minimal delay route paths for their subscribers. To this end, we present SLRouting, a novel Interior Gateway Routing Protocol. SLRouting calculates a composite route metric using packet waiting delays of servers and routers as well as the packet propagation delay of network links. SLRouting computes the route matrix by selecting the minimal delay path for destination networks. This paper presents the first version of the SLRouting including its theory, design, and implementation notes. A prototype of the proposed protocol is implemented using the ns-3 simulator, and the results were used to evaluate the proposed protocol.

Router-based request redirection management for a next-generation content distribution network

The increase in the amount of digital data transferred between contents Servers and Clients in a network causes problems created by congestion when downloading big web files, streaming media, etc. Content Delivery Networks (CDNs) are introduced to overcome such problems by redirecting the Clients request to the nearest Server. However, as the number of people accessing Internet increases rapidly, the performance of CDN is reduced, resulting in network congestion at times. To solve these problems, we propose an architecture in which a new management method is employed to redirect the Clients request using a content-based Router called the Service-oriented Router (SoR). This method is more effective than the currently implemented, traditional DNS-based request redirection (RR). The SoR is a special router that can perform a deep packet inspection of the packet streams. Our experiments were based on analytical modeling as well as test bed experiments, and they confirmed that the response time in the Router-based RR was less than that in the DNS-based RR by 23.3%. In addition, our test bed experiments showed that the RTT in the Router-based RR is less than that in the DNS-based RR by 7.7%.

Shutter control for cooling air flow management in data center servers

The growth of energy consumption in data centers is becoming one of the significant problems all over the world. The power usage of IT devices and air-conditioning (AC) units accounts for up to three-quarters of total energy consumption in typical data centers. This study discusses the effectiveness of using shutter-controlled air flow management to control cold air flow into the servers. It can impact the power consumption of both, the servers and the AC units. A raised floor data center has two types of aisles - cold and hot. In most cases, excessive volumes of cold air are pumped into the servers using cold aisles. We are proposing the utilization of a shutter to control the air flow and reduce wastage while preventing damage due to increased CPU temperature. The shutter is intended to control the air flow and maintain the temperature appropriately according to the workload of the servers. We evaluated the proposed system for controlling the flow of air into the servers. The results show that cold air volumes can be reduced by up to 92% while maintaining appropriate control of CPU temperature.

Per hop data encryption protocol for transmission of motion control data over public networks

Bilateral controllers are widely used vital technology to perform remote operations and telesurgeries. The nature of the bilateral controller enables control objects, which are geographically far from the operation location. Therefore, the control data has to travel through public networks. As a result, to maintain the effectiveness and the consistency of applications such as teleoperations and telesurgeries, faster data delivery and data integrity are essential. The Service-oriented Router (SoR) was introduced to maintain the rich information on the Internet and to achieve maximum benefit from networks. In particular, the security, privacy and integrity of bilateral communication are not discoursed in spite of its significance brought by its underlying skill information or personal vital information. An SoR can analyze all packet or network stream transactions on its interfaces and store them in high throughput databases. In this paper, we introduce a hop-by-hop routing protocol which provides hop-by-hop data encryption using functions of the SoR. This infrastructure can provide security, privacy and integrity by using these functions. Furthermore, we present the implementations of proposed system in the ns-3 simulator and the test result shows that in a given scenario, the protocol only takes a processing delay of 46.32 μs for the encryption and decryption processes per a packet.