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Performance Evaluation of Ipv4/Ipv6 Networks for Ubiquitous Home-Care Service

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Performance Evaluation of Ipv4/Ipv6 Networks for Ubiquitous Home-Care Service JOURNAL OF ELECTRONIC SCIENCE AND TECHNOLOGY, VOL. 11, NO. 3, SEPTEMBER 2013 241 Performance Evaluation of IPv4/IPv6 Networks for Ubiquitous Home-Care Service Cheng-Chan Hung and Shiow-Yuan Huang Abstract⎯ Because of rapid development in network the Bluetooth (IEEE 802.15.1), Zigbee (IEEE 802.15.4), technology, Internet usage has become widespread. It wireless fidelity (Wi-Fi), 3G or 3.5G (high speed downlink allows users with sensing devices to obtain medical data packet access, HSDPA) generation universal mobile for healthcare, such as physiological signals, voice, and telecommunications system (3G[2] or 3.5G[3] UMTS), and video streams from telemedicine systems, and to send WiMax[4],[5] networking technologies. However, all of these the healthcare data to back-end database systems, wireless technologies are connected to the Internet via a creating a ubiquitous healthcare environment. However, mobile sensor gateway that connects the wireless network this environment requires a widespread and suitable to the backbone network by establishing an IPv6 tunnel and network. IPv6 (Internet protocol version 6) is the translating IPv4 to IPv6. General gateways, such as the next-generation Internet protocol that will be the ADSL (asymmetric digital subscriber line) modem, cable protocol of future networks; it improves many modem, and FTTH (fiber to the home) or FTTB (fiber to shortcomings of IPv4. In this paper, we propose an the building) by VDSL (very high data rate digital IPv6/IPv4 U-home-care test system and analyze the subscriber line), connect LANs (local area network) to ISPs network’s parameters though a series of tests by (Internet service provider), serving as transmission media adjusting network parameters to find the optimal design gateways associated with different transmission media. The for applications in the IPv6/IPv4 U-home-care service so introduction of high-speed data rates, wide bandwidth, and as to assure good performance and high quality. digital and encrypted communication technologies enable Index Terms⎯Healthcare, Internet protocol version the delivery of audio, video, and medical data everywhere. 6, performance, telemedicine, ubiquity. All of above improve on some of the limitations existing m-health technologies[6] and provide a better platform for U-care services. 1. Introduction Most current home networks are asymmetrical networks[7] where the uplink bandwidth is smaller than the As a consequence of development in science and downlink bandwidth. This asymmetry is because more data technology, the medical sensing technology is evolving is downloaded than uploaded in general Internet use. This, from the previous electronic care (e-care) and mobile health however, may cause some problems for telemedicine data (m-health) to ubiquitous care (U-care). What is meant by transmission because sensing data must be uploaded. ubiquity? It means that it covers mobility of sensor Furthermore, the common Internet protocol of networks is networks, security, standards, integration (health system, service model), CAD (computer-assisted decision), and IPv4 (Internet Protocol version 4). IPv6 (Internet Protocol U-home-care (U-healthcare at home). Ubiquitous version 6) is the next generation Internet protocol and has computing[1], also called pervasive computing, describes many new features, such as large address space, Internet environments where a user is surrounded by numerous operations support, an extension of the encrypted special-purpose applications running on networked authentication mechanism, enhanced addressing information appliances. It is characterized by physically capabilities, an automatic addressing mechanism, embedded sensor systems, a ubiquitous network, and simplification of the header format, etc. Therefore, using application-specific devices. IPv6 is an asset for U-care networks, and the requirements of U-care networks are listed in Table 1. But, recently, in Recently, there has been an increase in research focused [8] on the production of commercial U-care systems based on the mostly performance evaluation of telemedicine , IPv4 networks are usually used. In our research, we analyze the performance of IPv6 Manuscript received February 17, 2013; revised April 2, 2013. C.-C. Hung is with the Department of Computer Science & Information and IPv4, which transmit UDP (user datagram protocol) Engineering, Asia University, Taichung 41354 (e-mail: cctks.hung@ and TCP (transmission control protocol) packets in msa.hinet.net). U-home-care systems. The TCP is a connection-oriented S.-Y. Huang is with the Department of Photonics and Communication protocol in which the TCP packets are transmitted before it Engineering, Asia University, Taichung 41354 (Corresponding author e-mail: [email protected]). establishes a connection. It is a reliable delivery mechanism Digital Object Identifier: 10.3969/j.issn.1674-862X.2013.03.001 for data transmission. On the other hand, UDP is a 242 JOURNAL OF ELECTRONIC SCIENCE AND TECHNOLOGY, VOL. 11, NO. 3, SEPTEMBER 2013 connection-less protocol and is unreliable, but it has the 2.1 Transmission Parameters and Category of advantage of high transmission efficiency. Thus, UDP is Networks in U-Healthcare Networks often used to transmit real-time voice and video data on The U-home-care service has three parts: physiology networks, but it needs to meet a higher QoS (quality of data (vital signals), voice, and video streams[9]. In this paper, service) requirement for telemedicine data transmission. we discuss the buffer size needed to support medical For these reasons, we decide to evaluate the network services to assure that no packets are dropped during protocols that are most suitable for U-home-care in the transmission. A buffer size of 12 packets for audio service, future. four packets for medical data, and 25 packets for video This paper is organized as follows: Section 2 focuses on service are required. But in the case of [9], an IPv4 medical the U-healthcare requirements of the project and the service network was used. Therefore, in this paper, we will description of the QoS requirements in U-healthcare evaluate the requirements for medical data, voice, and networks. Section 3 describes the scenarios of U-home-care video streams, and measure the value of delay, jitter, and in two types of networks. Section 4 illustrates the packet loss, and try to find the differences between measurement models that we use to test the application U-healthcare networks using IPv6 and IPv4. Most current networks in Taiwan access the Internet via platforms of the U-home-care environment. Section 5 [7] focuses on the performance requirements of medical video ADSL (79.2%) , Fiber (8.8%), and Cable Modem (7.2%) networks are also used[7]. The characteristics of ADSL data, voice data, and data used in U-home-care. Section 6 networks are that the uplink and downlink bandwidths are concludes with a summary and areas for future research. asymmetrical, and the uplink bandwidth is relatively small. However, most U-healthcare data are uplink and 2. U-Healthcare Requirements transmitted from a client to a back-end server. Therefore, to structure a U-healthcare environment for the future, we Along with social and economic developments, medical must consider the issue of ADSL in IPv4 and IPv6 advances have enabled people to increase their life U-healthcare networks. expectancy with the consequent gradual aging of the population. The problem of an aging population needs 2.2 Data Rate and QoS Requirements of U-Healthcare urgent attention in the 21st century. Most healthcare applications can be divided into three The increasing demands of healthcare for the elderly are kinds: 1) medical data transmission, mainly ECG the most pressing current need and will continue to grow in (electrocardiogram), EEG (electroencephalography), and the future. Therefore, as we consider the increasing blood pressure, etc.; 2) audio from a stethoscope or VoIP demands for healthcare for the elderly that may include communication applications; and 3) motion video and mobile care (m-care), it is necessary to establish a new type endoscopic video transmission. Each has different data rate of healthcare system that uses the network technology to transmission requirements and QoS (quality of service) requirements. provide U-care services. When a person urgently needs Problems with network QoS can be recognized by the healthcare, the U-healthcare system can issue an immediate packet loss, jitter, and delay. These can be further divided warning through the network so to enable healthcare into two categories: their affect on medical multimedia and workers to locate the person quickly and efficiently and medical data. Regarding medical multimedia, the human provide the necessary emergency treatment. ear cannot detect delay below 150 ms of end-to-end delay, Table 1 shows the requirements of a U-healthcare so voice jitter or delay cannot be more than 150 ms for the network and the solutions IPv6 provides. digital audio stethoscope. We refer to [10], where the acceptable delay was about 400 ms. But [11] mentioned that Table 1: Requirements of U-care and characteristics in IPv4/v6 networks a reasonable delay goal was 250 ms, and for private networks it was 200 ms. For this reason, we chose a delay Requirements of Feature of IPv6 Feature of IPv4 goal for our network of less than 250 ms as a standard U-care network requirement. Large number of Large IP space Will be exhausting Medical data also can be divided into two types: medical sensors real-time
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