New speeds for FC protocols.The need for speed has been one of the underlying themes in the computing computing - computer world since the beginning of the industry. As the raw volume of storage compounds annually, the need to access, protect and manage that storage places greater demands and challenges on IT managers. How does the market keep up? Higher performance at the same or lower cost has been the typical response of the SAN market. The storage networking market, like all segments of the computing world, is bringing improved cost and performance to enterprise IT customers. However, enterprise IT organizations are under constant pressure to improve and scale their capabilities with relativity static budgets. The next step in high-speed Fibre Channel (FC) protocols will meet this need. Vendors of these products are working together to ensure that the next step in FC performance protects current investments and provides a rational implementation path for introducing incremental Additional or increased growth, bulk, quantity, number, or value; enlarged. Incremental cost is additional or increased cost of an item or service apart from its actual cost. capabilities to SAN environments. Killer Apps A software application that is exceptionally useful or exciting. Killer apps are innovative and often represent the first of a new breed, and they are extremely successful. For example, in the late 1970s, the VisiCalc spreadsheet was the killer app for the Apple II, providing reason Demand More Data Bandwidth At the recent Gilder/Forbes storage conference. Steve Duplessie, analyst for Enterprise Storage Group, stated: "The average storage administrator's data management load will have increased from 760GB in 2000, to upwards of 6TB in 2003." Serverless backup A type of LAN free backup that does not use any of the resources of an application server or a backup server. See LAN free backup. , storage consolidation and database storage continue to reign as the killer applications Killer Application Killer application or "killer app" is a buzzword that describes a software application that surpasses all of its competitors. Notes: The term is sometimes used to describe a type of software. of the SAN. The increased demands these applications place on the SAN will show that current data rates will not be sufficient in the near future. Furthermore, backup windows will face greater challenges and access demands will grow with increased use of online versus offline storage Refers to disks and tapes that are kept in a data library. Offline data cannot be accessed from a computer or terminal until it is mounted in the drive. . Pushing Performance The performance of the entire SAN ultimately rests on the performance of the venerable disk drive. The basic math of disk drives is as follows: Data Density X Speed of Platter One of the disks in a hard disk drive. Each platter provides a top and bottom recording surface. There may be only one or several platters in a drive with each platter having its own pair of read/write heads. See magnetic disk. = Performance Required at the Interface As disk drives continue their climb toward increased capacity (data density) and the performance of the disk improves (speed of platter), the interface performance requirements also increase. Today, the fastest disk drives use 2Gbps FC. As performance of the disk drive increases, it is clear that by the end of 2004, 2Gbps will no longer meet the interface performance requirements of disk drives. This will be the first step in the high-speed FC market and it will be the driving force of improvements in SAN bandwidth. All of the major manufacturers of disk and tape drives have stated that 4Gbps will be their next step in interface connectivity. Industry leaders from Seagate, Hitachi, Fujitsu, Quantum and Agilent are moving forward with 4Gbps products to meet this market requirement. "The performance of our disk drives demands the next step in Fibre Channel performance and that will be 4Gbps," concurs Mike Chenery, vice president of advanced technology for Fujitsu. "Connector cost and configuration issues are also a leading driver toward 4Gbps versus 10Gbps at the device level." "Our customers are currently achieving 160MB/s with the DX100 enhanced backup product, which is close to saturating current 2Gb/s Fibre Channel," stated Rory Bolt, chief storage architect for Quantum. "This year we will add compression to the DX100 that will drive data rates over 300MB/s and we could definitely leverage the performance of 4Gbps. As we advance our tape platforms with embedded Inserted into. See embedded system. switching and other technologies for aggregating multiple drives behind a single FC port, we view 4Gbps as a viable method to optimize optimize - optimisation performance and cost." Industry analysts see 4Gbps as an obvious next step in the SAN market. "We went from 1Gbps to 2Gbps long before the performance was required because OEMs could provide greater performance and incremental value for the same price," said Tony Prigmore, senior analyst for Enterprise Storage Group. "Four Gbps offers the same value proposition and is driven by real storage needs. It is great when technology can be developed at a price and performance level that anticipates the pain point, but can be deployed with today's dollars." As the SAN market follows the disk and tape drive world, this new increment To add a number to another number. Incrementing a counter means adding 1 to its current value. of performance will have a ripple effect ripple effect Epidemiology See Signal event. in SAN infrastructures installed today and to be installed tomorrow. Based on performance changes of disk and tape drives, the performance needs of RAID will change and this, in turn, will drive new requirements for increased performance in switches, routers, gateways and, ultimately, server connections via Host Bus Adapters See host adapter. (HBAs). The question in the storage industry is not if new high-speed Fibre Channel technologies will be introduced, but rather "when" and "how" they will be implemented. Implementing High-Speed FC As disk and tape drive manufacturers march toward higher speed Fibre Channel to meet the needs of enterprise IT shops, the debate becomes which high-speed alternatives make the most sense, and how should they be implemented. There are two Fibre Channel options, 4Gbps and 10Gbps. Ten Gbps offers a 5X improvement over existing 2Gbps Fibre Channel technology. This performance gain is unprecedented in current I/O (Input/Output) The transfer of data between the CPU and a peripheral device. Every transfer is an output from one device and an input to another. See PC input/output. I/O - Input/Output technology that, traditionally, has enjoyed a much more linear 2X performance improvement. With this quantum jump quantum jump n. 1. Abrupt change from one energy level to another, especially such a change in the orbit of an electron with the loss or gain of a quantum of energy. 2. A quantum leap. in performance comes significantly higher headroom head·room n. 1. Space above one's head, as in a motor vehicle, above a doorway, or in a tunnel; clearance. 2. Electronics Dynamic headroom. to handle the I/O bandwidth required in data centers. However, 10Gbps sacrifices compatibility with current 2Gbps Fibre Channel and introduces a significant cost increment for this maximum level of performance. Although 4Gbps is not as significant a performance gain as 10Gbps, it offers compelling benefits such as a less technologically complicated development path (meaning faster to market), backward compatibility See backward compatible. (jargon) backward compatibility - Able to share data or commands with older versions of itself, or sometimes other older systems, particularly systems it intends to supplant. with 2Gbps, investment protection and cost parity parity or space parity, in physics, quantity that refers to the relationship between an object or process and the image that it can produce in a mirror. with existing 2Gbps technology. Due to the unique advantages of both 4Gbps and 10Gbps, there are logical adoption phases and segments for both technologies. The following implementation areas will take advantage of one or both of the high-speed FC options over the next several years: * Storage subsystems The part of a computer system that provides the storage. It includes the controller and disk drives. See storage system. with new 4Gbps devices and device controllers * Inter-switch link applications * Server connections * Storage Subsystems I/O Evolution One key way to understand where new Fibre Channel technology will be deployed is to look for bottlenecks and the lowest impact to existing infrastructure. In fact, by late 2004 or early 2005, disk and tape drives will be capable of delivering burst data rates in excess of 200MB/s which will easily exceed today's 2Gbps FC bandwidth. This means that Not only do the devices have to move to 4Gbps, but the device controllers at the core of storage subsystems must change as well. It is likely that storage systems will upgrade to 4Gbps, which is compatible with existing 2Gbps SANs, providing excellent near-term interoperability The capability of two or more hardware devices or two or more software routines to work harmoniously together. For example, in an Ethernet network, display adapters, hubs, switches and routers from different vendors must conform to the Ethernet standard and interoperate with each other. and investment protection before the entire SAN moves to 4Gbps. In addition, 4Gbps will be at cost parity with 2Gbps. The result is that IT shops will be able to get more performance without additional cost and meet the increasing demands placed on their SANs. Upgrading the backside BACKSIDE, estates. In England this term was formerly used in conveyances and even in pleadings, and is still, adhered to with reference to ancient descriptions in deeds, in continuing the transfer of the same. property. storage units to 4Gbps can be done with existing 2Gbps fabrics as a first step. Second, if this is combined with a switch upgrade to 4Gbps on the fabric side, performance to all servers connected to the switch will be improved. It will probably be 2006 or 2007 before storage devices will be able to take advantage of 10Gbps. Fortunately, by 2006 or 2007, anticipated cost reductions in 10Gbps cost structure and resolution of technical hurdles will start allowing 10Gbps to become a logical choice for storage systems. [FIGURE OMITTED] Inter-Switch Link Applications Fibre Channel switches Major manufacturers of Fibre Channel switches are: Brocade, Cisco, McData and Qlogic.
E-mail: Bill Janssen <janssen@parc.xerox.com>. ports is typically 10:1; that is, IT managers will generally have ten 2Gbps Fiber Channel ports dedicated for servers and storage devices for every ISL port between switches. When ISLs have to provide bandwidth for all of the other data aggregated through the switch they can often become a bottleneck A lessening of throughput. It often refers to networks that are overloaded, which is caused by the inability of the hardware and transmission lines to support the traffic. It can also refer to a mismatch inside the computer where slower-speed peripheral buses and devices prevent the CPU . Logic would dictate that the ISL port should be faster than the incoming 1Gbps or 2Gbps ports. Today, however, that is not the case. Enterprise IT managers must use multiple 2Gbps ports to meet this need, requiring a higher number of switches and raising the price of SAN connectivity. Since ISL port counts and cabling are a constant issue for SANs, reducing the physical number of cables and ports by using higher bandwidth ISLs is a clear benefit to the IT manager. Using new high-speed Fibre Channel technology can dramatically reduce the number of ISL ports. There are several technological and cost issues to consider. Four Gbps offers the benefits of faster time to market, lower cost, and incremental performance while providing backward compatibility. In the Table, you can see how moving to high-speed Fibre Channel can reduce the number of ports required for ISLs and improve the ROI (Return On Investment) The monetary benefits derived from having spent money on developing or revising a system. In the IT world, there are more ways to compute ROI than Carter has liver pills (and for those of you who never heard of that expression, it means a lot). of the switch in the SAN. In the future, 10Gbps ISLs may be the only practical way to connect director-class switches A fault-tolerant Fibre Channel switch that typically has a high port count and may serve as a central switch to other fabrics. See Fibre Channel. together given the demands of the storage traffic. Ultimately, it is expected that by 2006, 10Gbps optics will be cost competitive with current FC solutions and further improve enterprise IT investments in SANs. The Server Connection When selecting Fibre Channel HBA (Host Bus Adapter) See host adapter. solutions for servers, one of the key goals is to match the performance of the server bus and the HBA protocol. Today's PCI-X (PCI eXtended) An enhanced PCI bus technology originally developed by IBM, HP and Compaq that is backward compatible with existing PCI cards. PCI and 32-bit PCI-X slots are physically the same, and PCI cards can plug into PCI-X slots. system buses run at 133MHz (MegaHertZ) One million cycles per second. It is used to measure the transmission speed of electronic devices, including channels, buses and the computer's internal clock. A one-megahertz clock (1 MHz) means some number of bits (16, 32, 64, etc. and deliver 1GB/s of raw performance (8 bytes * 133MHz/s = ~1GB/s) to the server. After various overheads are taken into account, the system is probably realizing about 0.8GB/s. The data rate of 4Gbpsec FC is 800MB/sec, which is a good performance match for PCI-X 1.0. PCI-X 2.0 at 266MHz would be a better match for 10Gbps, because it delivers closer to 2GB/s, which can better handle full speed of 10Gbps (800 MB/s) Fibre Channel (see Figure). First implementations of PCI-Express deliver 10Gbps (2.5Gb/sec across each of four physical lanes), or roughly 1GB/s full duplex (Computers) arranged so that the information may be transmitted in both directions simultaneously; - of communications channels between computers; contrasted with After reviewing the Figure, considering the relative performance matching of 4Gbps to current and next-generation server buses, it becomes clear that the cost and compatibility advantages of 4Gbps provide a compelling case for considering 4Gbps for the next step in high-speed Fibre Channel solutions. Given the analysis above, it's likely that 4Gbps-ready solutions will be deployed over the next two to three years and 10Gbps, at the server level, will be deployed in 2006 and beyond. The following chart details the bus bandwidth capability of the emerging server bus interconnects now and on the horizon. The Bottom Line Ultra-High Performance at Any Cost: 10 Gbps Fibre Channel is the highest performance per cable technology available to the IT manager. As a result, those who are ready to pay the premium in the near term will want to stay abreast of the developments in this area. Densely populated pop·u·late tr.v. pop·u·lat·ed, pop·u·lat·ing, pop·u·lates 1. To supply with inhabitants, as by colonization; people. 2. and bandwidth-hungry director-class ISL applications will be the logical first deployment category for this technology. 4Gbps Cost Parity: Four Gbps Fibre Channel is projected to have a similar cost structure of 2Gbps FC. This follows the traditional speed doubling history of storage I/O, which allows for improved performance at the same price as prior technologies. For cost-conscious IT managers, 4Gbps makes clear and intuitive sense for the next few years of deployment for ISL, switch port, server and storage fabric applications. Backward Compatibility and Investment Protection: Four Gbps FC's ability to auto-negotiate on SANs that can only operate at 2Gbps is a major advantage for the IT manager. System administrators will not pull out entire 2Gbps infrastructures at once. New 4Gbps HBAs may be added, for example, as new servers are added. Even though they will run at 2Gbps, a day will come when the switch is upgraded to 4Gbps and then--presto--the HBAs will operate at the higher frequency (this is known as 4Gbps "ready"). This is an enormous advantage to the IT manager who can't afford the risk (and potential expense) of upgrading everything to the next speed point all at once. Four Gbps FC technology is a boon Boon A general term that refers to a benefit or improvement for investors. This can include such things as increased dividends, a stock market rally and stock buybacks. Notes: , therefore, to those needing to maintain backward compatibility in the near term and investment protection in anticipation of the eventual upgrade of the remainder of the SAN to 4Gbps. The Right Technology at the Right Time: The choices in high-speed Fibre Channel involve the right combination of incremental performance in the right technology windows. It is clear that 4Gbps will be the near-term solution for disk and tape storage. It is also apparent that the fabric connections between storage platforms and switches will need incremental performance and the traffic will be shared between 4Gbps and 10Gbps depending on the need of the platform at a given time. Finally, it's also evident that server buses will be ready and able to leverage 4Gbps performance long before 10Gbps is viable in the server. The Right SAN Investment: Enterprise IT shops require more than the latest technology. They need vendors who protect their current SAN investments and provide reasonable migration paths to new technology. Already the leading provider of 2Gbps Fibre Channel technology. QLogic is leading the industry in development of high-speed FC solutions. Whether your needs are for the absolute highest performance at 10Gbps Fibre Channel, or the backward compatibility and evolutionary step up in speed at 4Gbps, QLogic has the products to fit your needs. What to do Next? Consider the following three evolutionary steps when upgrading a SAN infrastructure: * When buying new servers, look for HBAs that are "4Gbps Fibre Channel ready." This will "future proof" your SAN and get you ready to double your line rate without changing a single HBA as you upgrade your switches. * When upgrading your switches, look for products containing QLogic switch ASICs. Since QLogic creates both 4Gbps and 10Gbps switch technology, you will be sure to get the right technology for now and the future. * When buying storage devices, look again to QLogic ASIC (Application Specific Integrated Circuit) Pronounced "a-sick." A chip that is custom designed for a specific application rather than a general-purpose chip such as a microprocessor. products as the "engines inside." This way, you'll be sure to get both 4Gbps and 10Gbps Fibre Channel ports where and when you need them. Table ISL Bandwidth 2Gb/s ISL 4Gb/s ISL 10Gb/s ISL Requirements Ports/Cable Ports/Cable Ports/Cable 16 Gb/s 8 4 2 28 Gb/s 14 7 3 60 Gb/s 30 15 6 Shaun Walsh is managing partner at Excillio Group, Inc. (Rancho ran·cho n. pl. ran·chos Southwestern U.S. 1. A hut or group of huts for housing ranch workers. 2. A ranch. Santa Margarita Santa Margarita ("Saint Margaret") may refer to:
www.excilliogroup.com www.qlogic.com |
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