carlson.docx
…
7 pages
Sign up for access to the world's latest research
Abstract
AI
AI
Storage Area Networks (SANs) are specialized high-speed networks providing block-level access to storage, essential for business-critical applications requiring high throughput and low latency. SANs consist of interconnected hosts, switches, storage elements, and devices, allowing for improved application availability, performance, and data protection. The paper discusses common SAN protocols, advantages such as real-time data access, streamlined application management, and the risks of data corruption, while also addressing challenges like high initial installation costs.
Related papers
International journal of smart sensors and ad hoc networks, 2012
The SCVM, which stands for Storage Concentrator Virtual Machine, creates IP SAN storage as virtual machine, providing the user with the ability to consolidate their virtual data center. The SCVM can fully manage and has features for the storage over local as well as networked VMs. This can be attained through virtual switch or physical network connection. It provides an advanced, fully featured iSCSI SAN / Storage within an SAN Server. The user does not need another box for the storage. One just has to create an iSCSI Virtual SAN Appliance along with the Server Virtual Machines within the same hardware platform. This is not only Increases the productivity, but also simplifies the management, and reduces the power and rack space by simply loading an SCVM in a Virtual Machine. By creating an iSCSI Target within a Virtual Server, SCVM's customers may reallocate existing hardware resources to create business continuity and disaster recovery solution. This is achieved by any of two ways, be it SCVM's synchronous mirroring within the datacenter and distributed campus, or be it the asynchronous mirroring (replication) between remote facilities. I.
2007
The Internet Small Computer System Interface (iSCSI) is a SCSI transport protocol that maps the SCSI family of application protocols onto TCP/IP. Datamover Architecture for iSCSI (DA) defines an abstract model in which the movement of data between iSCSI end nodes is logically separated from the rest of the iSCSI protocol in order to allow iSCSI to adapt to innovations available in new IP transports. While DA defines the architectural functions required of the class of Datamover protocols, it does not define any specific Datamover protocols. Each such Datamover protocol, defined in a separate document, provides a reliable transport for all iSCSI PDUs, but actually moves the data required for certain iSCSI PDUs without involving the remote iSCSI layer itself. This document begins with an introduction of a few new abstractions, defines a layered architecture for iSCSI and Datamover protocols, and then models the interactions within an iSCSI end node between the iSCSI layer and the Datamover layer that happen in order to transparently perform remote data movement within an IP fabric. It is intended that this definition will help map iSCSI to generic Remote Direct Memory Access (RDMA)-capable IP fabrics in the future comprising TCP, the Stream Control Transmission Protocol (SCTP), and possibly other underlying network transport layers, such as InfiniBand.
Proc. 12th NASA Goddard & 21st IEEE Conf. …, 2004
iSCSI is becoming an important protocol to enable remote storage access through the ubiquitous TCP/IP network. Due to the significant shift in its transport mechanism, iSCSI-based storage system may possess different performance characteristics from the traditional storage system. Simulation offers a flexible way to study the iSCSI-based storage system. In this paper, we present a simulation work of iSCSI-based storage system based on ns2. The storage system consists of an iSCSI gateway with multiple targets, a number of storage devices that are connected to the storage router through FC-AL and clients, which access the target through iSCSI protocol. We present the system model, the implementation of the components, the validation of the model and performance evaluation based on the model. Coupled with the rich TCP/IP support from ns2, the simulation components can be effortlessly used for the performance and alternatives study of iSCSI-based storage systems, applications in broad configurations.
Journal of Software, 2013
iSCSI is one of the most popular protocols among the storage area network (SAN) working on an IP network. iSCSI is a standard to encapsulate a SCSI command into a TCP/IP packet, thus we can make an access to a storage system with commoditized IP devices only. In this paper, iSCSI sequential write access for a remote backup system is focused. It is well known that iSCSI experiences performance degradation under a high latency environment. The storage access by iSCSI has multiple hierarchical protocols. Due to this complicated structure, it is very difficult to identify the performance bottleneck that causes the degradation. Therefore, system tools which can analyze the complicated layered structure are required. We have developed system tools that enable us to monitor the hierarchical protocols. As a result, we have identified the cause of the iSCSI performance degradation problem. We then fixed the problem and confirmed that one can obtain the performance close to the theoretical limit.
2009 International Conference on Advanced Information Networking and Applications Workshops, 2009
iSCSI has a problem of drastic performance deterioration in the case of longer-latency. Thus, we have optimized iSCSI remote storage access through multiple layers. As a result, when RTT is 32ms, performance of the optimized iSCSI has achieved quadruple of that of the default iSCSI. Moreover, we have constructed the model of iSCSI sequential access and analyzed the factor of iSCSI performance deterioration.
Symposium on Mass Storage Systems, 2002
The High Performance Storage System (HPSS) is a mature Hierarchical Storage Management (HSM) system that was developed around a network-centered architecture, with client access to storage provided through third-party controls. Because of this design, HPSS is able to leverage today's Storage Area Network (SAN) infrastructures to provide cost effective, large-scale storage systems and high performance global file access for clients.
2004
Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
2008 International Conference on High Performance Switching and Routing, 2008
iSCSI is a protocol standardized by IETF that runs on a TCPIIP network to transfer standard SCSI commands. In this paper, we evaluate the performance of iSCSI using standard PCs running a software implementation of the protocol, with the aim of assessing the performance of low-cost distributed storage solutions. First, we compare the performance when using a local disk with those of a virtualized disk connected through a standard Gigabit Ethernet LAN during file 110 operations. Then, we emulate the characteristics of a WANIMAN setup by using a software emulator within the Linux kernel to generate delays and packet losses, and evaluate the ability of iSCSI to offer Disaster Recovery solutions over high-speed long-distance links. We found that, even if TCP can be tuned to support links with large bandwidth-delay products, iSCSI does not reach good performance due to its windowing scheme that is not large enough, in the used software implementation, to support longdistance links. Finally, we test the iSCSI behavior when other types of traffic share network links with the iSCSI protocol.
In this paper, an IP-SAN access trace method is proposed and its implementation is presented. IP-SAN and iSCSI are expected to remedy problems of Fibre Channel (FC)-based SAN. Because servers and storage cooperatively work with communications through TCP/IP layer in IP-SAN system, an integrated analysis of both sides is considered to be sig- nificant for achieving better performance. Our proposed system can precisely point out the cause of performance degradation when IP-SAN is used for a re- mote storage access. In the experiment of parallel iSCSI ac- cess in a long-delayed network, the total performance is limited by a parameter in an implementation of the SCSI layer in the iSCSI protocol stack. Based on the result ob- tained with our IP-SAN access trace system, the parame- ter in the layer is modified. As a result, four times perfor- mance improvement is achieved compared with the default value case. Thus it is effective to monitor all the layers in the iSCSI protocol stack and e...
File and Storage Technologies, 2005
In this paper we present two novel techniques for improving the performance of the Internet Small Computer Systems Interface (iSCSI) protocol, which is the basis for IP-based networked block storage today. We demonstrate that by making a few modifications to an existing iSCSI implementation, it is possible to increase the iSCSI protocol processing throughput from 1.4 Gbps to 3.6 Gbps. Our solution scales with the CPU clock speed and can be easily implemented in software using any general purpose processor without requiring specialized iSCSI protocol processing hardware. To gain an in-depth understanding of the processing costs associated with an iSCSI protocol implementation, we built an iSCSI fast path in a userlevel sandbox environment. We discovered that the generation of Cyclic Redundancy Codes (CRCs) which is required for data integrity, and the data copy operations which are required for the interaction between iSCSI and TCP represent the main bottlenecks in iSCSI protocol processing. We propose two optimizations to iSCSI implementations to address these bottlenecks. Our first optimization is on the way CRCs are being calculated. We replace the industry standard algorithm proposed by Prof. Dilip Sarwate with 'Slicing-by-8' (SB8), a new algorithm capable of ideally reading arbitrarily large amounts of data at a time while keeping its memory requirement at reasonable level. Our second optimization is on the way iSCSI interacts with the TCP layer. We interleave the compute-intensive data integrity checks with the memory access-intensive data copy operations to benefit from cache effects and hardware pipeline parallelism.
yonnah okuna