اسم الباحث :
Mothana Mohammad AL-aswad PHD.KHALIL ALWAJEH
Abstract iSCSI is a newly emerging protocol with the goal of implementing the Storage Area Network (SAN) technology over TCP/IP, where enables to access to remote data that in attached storage disks storages-Direct Attached Storage(DAS) over IP-networked. Also it's brings economy and convenience whereas it also raises performance and reliability issues. This paper investigates about possibility, using storage technology of the SANs, and iSCSI-SAN protocol, to improve access to attached storage disks storages in local system, with using iSCSI-SANs as virtual storage, is rather than DAS storage in local system of PC. Explicates after experiment procedure is that improving throughput of iSCSI-SANs was better than attached storage disks storages - DAS in local system at about %445. This means is that it can use iSCSI-SANs in local system of PC as attaché storage disks storages as DAS, where was become fact not possible, without cost, high performance, and easy control. Keywords: SAN, iSCSI-SANs, DAS, iSCSI-SAN Protocol, SCVM In the past few years have seen a tremendous growth in the amount of data. Huge amounts of new data are generated by humans every year. This is because of the humans and applications uses are huge amounts of data in various format including texts, video, audio and images. Leading to the increasing requirement for large storage repositories, for storage of this large data. Single attached disks and old storage technologies cannot manage the storing these amounts of data[1]. DAS is using the Small Computer System Interface (SCSI) commands. However DAS with SCSI, has some limitations from these limitations. It have not, high speed, high capacity, high availability and scalable, was storage of data are done over local system or over networks. Until emerging studies new are said, enables from the access to remote data that in attached storage disks storages-DAS over IP-networked, with storage technology of the SANs, and with using iSCSI-SAN protocol [1,2,3,4,5,6]. This are paper will be studying are (SANs, iSCSI protocol) and paper investigates about possibility, the improving of access to attached storage disks storages that in local system, with using using storage technology of the SANs, and internet SCSI-SAN (iSCSI-SAN) protocol. Where will be using SANs as virtual storage iSCSI-SANs is rather than DAS storage in same local system. The Storage Concentrator Virtual Machine (SCVM), creates iSCSI-SANs storage as virtual storage. It provides an advanced, fully featured iSCSI-SAN Storage within an SAN Server [2]. From through do are conversion attached storage disks storages-DAS to a virtual storages are called iSCSI-SANs. The reaching to iSCSI-SANs is procure with using iSCSI-SAN protocol, over IP-networked. Where focused about evaluation of performance of iSCSI-SANs as storage system is using in local system, and is compare it with DAS storage, in same system, with new benchmark tool called IOMeter[7]. Clear after experiment procedure is that improving throughput of iSCSI-SANs in terms of (I/Os, MB/s), and average response time in different block sizes of the (I/O) request, was better than DAS in local system about %445. The performance of iSCSI-SANs is better than DAS in local system, and was satisfactory. All storage are captive to an individual PC or computer platform, such as a laptop, a desktop PC, or a single server in a small business, disk storage usually resides inside the processor enclosure and is a simple form of DAS. DAS devices depend on the host OS to handle I/O. SCSI is used as a connection medium in DAS and carries and controls the blocks between the host and attached device. However DAS and SCSI has some limitations these limitations, scalability is one of the them, the other limitation in SCSI is low number of devices that can be serviced at the time, the maximum number of attached devices to bus topology can be support by SCSI is around fifteen, because of affecting to the performance of the system these number can be decrease to four or five. The other limitation on DAS, was the availability and reliability of the system. In DAS, all DAS devices share the same cable. With the numbers of DAS devices constantly increasing, the cable between DAS and host may be very busy. Thus, the system performance is affected. In SCSI, because of the large number of cables the probability of system failure is also high and any failure in cables that connects to the storage devices can cause a system failure and lose the connectivity and data to applications. The other limitations of SCSI protocol is related to the speed and distance that can be supported by this protocol, the maximum of 25 meters long distance makes the SCSI protocol not a convenient solution for long distances[1]. All this the problems of DAS are making from DAS not the suitable storage for be the storage system very much vital, has high speed, high capacity, high availability and scalable, was storage of data are done over local system such as PC or over networks. But emerging studies new as will mentioned later in related studies, to is solve and enable from access to remote data that in DAS storages over IP-networked, with using storage technology of the SANs, and iSCSI-SAN protocol [1,2,3,4,5,6], as shown in figure 2. The paper aims at improving the storage in local system of PC, with the help of iSCSI protocols and SANs technology , DAS can be efficiently utilized, in local system of PC, to try the improve of performance of storage in it, where will using the iSCSI-SANs and iSCSI protocol is rather than DAS storage that is using SCSI protocol, and as well, this paper studies SANs, iSCSI protocol. Presently, SAN are widely used, and have become the most important solution to improve storage performance and reliability. The storage networks in SAN systems commonly use fiber networks and fiber channel (FC) disks as storage medium. However, the high cost of fiber networks and fiber disks make SAN expensive. In addition, the difficulties in controlling and expanding fiber disk arrays make it hard for customers to include their present disk arrays into the SAN systems, thereby wasting existing resources. These problems limit the application of SAN systems [8]. So recently, the emerging of iSCSI protocol, which approved by the Internet Engineering Task Force(IETF) in 2003. iSCSI-SANs operate at 1 Gbps Ethernet speeds, though this could increase to 10 Gigabit Ethernet (GBE) as existing Network Interface Cards(NICs) and switches are upgraded to accommodate 10 GigE [9]. The figure 1 is showing uses of iSCSI protocol, as gateway to enables applications on an IP network to use an iSCSI Initiator to connect to FC Targets. The iSCSI gateway translates iSCSI protocol to FC Protocol (FCP), bridging the IP network and FC-SAN [11]. To providing a SAN over the 10 Gb/Sec, iSCSI makes it available to use the high-speed and high performance devices over the IP infrastructure, use the low cost IP- based devices such as switches and routers are closely compete with FC in terms of performance, speed and cost[1]. IP SAN is also known as iSCSI-SAN for the protocol it employs, the names are generally interchangeable for this discussion. The development of an iSCSI protocol for an SAN environment that uses a common SCSI protocol to replace an FC protocol to be can significantly improve the SAN's performance/price ratio and flexibility [8].
سنة النشر :
2017
ملخص البحث :
