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Prepared By
Name: Muhammad Umair Shaikh Roll# NI-F7-BBA-212
Removable Storage Device
Removable storage has been around almost as long as the computer itself. Early removable storage was based on magnetic tape like that used by an audio cassette. Before that, some computers even used paper punch cards to store information! We have come a long way since the days of punch cards. New removable storage devices can store hundreds of megabytes (and even gigabytes) of data on a single disk, cassette, card or cartridge. In this article, you will learn about the three major storage technologies. We'll also talk about which devices use each technology and what the future holds for this medium. But first, let's see why you would want removable storage.
Punch cards like the one above had holes that the computer interpreted as specific information.
Portable Memory
There are several reasons why removable storage is useful: Commercial software Making back-up copies of important information Transporting data between two computers Storing software and information that you don't need to access constantly Copying information to give to someone else Securing information that you don't want anyone else to access
Photo courtesy Iomega Corporation A tiny hard drive powers this removable storage device.
Modern removable storage devices offer an incredible number of options, with storage capacities ranging from the 1.44 megabytes (MB) of a standard floppy to the upwards of 20-gigabyte (GB) capacity of some portable drives. All of these devices fall into one of three categories:
Magnetic storage Optical storage Solid-state storage
History of Removable Storage Medium
The rise of the mobile data market has been rapid, lucrative and dangerous. Long gone are the days when you needed identical tape drives and software on both computers. The traditional floppy disk market and local tape markets were superseded by the super-floppy and zip drive. Now even they are disappearing as the mobile data storage market evolves.
Thanks to their large capacities, portability, and simplicity, removable media have become one of the most popular types of storage devices around today. You've only to go down to one of the big computer shows to be offered a free memory stick as a stand give-away. If you take part in an IT training course, you might be given one with all your computer course notes stored on it. They are so cheap it's the obvious way to store information, business proposals, accounts, client's details, marketing plans etc
The arrival of the MP3 music player has had a significant impact on the market. While Apple sees music as the only reason for owning an iPod, their competitors have simply created large USB stores with some built in music software. An increasingly number of people now views the MP3 player as both a data and entertainment tool. The danger here is that as an entertainment device it falls below the radar and with storage capacities set to exceed 80GB by the end of 2005; it is a serious threat to data protection. Here are 10 things you probably don't know about this market. 1. The first Compact Flash Drives began to appear in quantity five years ago and started at 8MB. By 2004, Laxer had released an 8GB device aimed predominately at the professional photo-market. 2. USB Pen Drives are now often hidden inside pens making them very difficult to detect by security teams. 3. Seagate now ships a proper, very small form factor 5GB USB disk drive. It is less than half the size of a Yo-Yo and features a real disk drive spinning at 3600 RPM. 4. 4GB USB pen drives are expected to reach capacities of over 8GB by mid 2005. 5. New mobile phones can use memory cards holding in excess of 1GB 6. Research in 2004 suggested that a modern office worker carrying an MP3 device and a mobile phone would be capable of storing over 20GB of data. 7. MP3 and mobile video player company Archos will soon launch a 100GB device. 8. The new 1-inch hard disks are expected to reach 100GB within 12 months. 9. Blocking the USB port would prevent all devices from working and with operating systems like Windows XP, is easy to circumvent. 10. IDC predicts that the sale of very small hard disks will explode from less than 18 million in 2004 to over 100 million in 2008. Most of those will be in portable devices that could be carried into offices. Disk labs Computer Forensics Experts at Disk labs are able to retrieve incriminating evidence (or prove innocence) to prosecution and defense clients. Disk labs can provide email analysis, RAID forensics, mobile phone full and server forensics. If this doesn't scare you then you clearly are not responsible for looking after corporate security. Here are some facts about corporate data: 1. The average word processing file is 3 pages in length and between 25k and 30k. That means that a 20GB MP3 player could hold over 750,000 documents. 2. The majority of corporate networks do not audit what data a user copies to a local machine or attached device. 3. New compliance legislation means that you must develop a policy for the use of devices or risk being fined by regulators. 4. 99% of users who use mobile devices to transfer data use no encryption to protect their contents.
Think about how easy it would be to remove your corporate data. During the 1980's the fear was that people would be able to save the customer or company price lists onto a floppy disk and take it to their next employer. Today, they can not only take that information but also your entire customer database showing purchasing prices and history on a single device. The advent of fast Internet access in the office meant that employees used the company network to download files. Increasingly, that has meant people pulling down illegal content as well as installing peer-to-peer networks on their desktop computer. With P2P installed, they can move files between the office and home on CD, DVD or other removable media. The danger to the corporate network is that file sharing through P2P exposes the company internal structure. Preventing people bringing devices and media into the office is an extremely difficult problem. Look at the physical size of much of this media and it's easily missed in a pocket, briefcase or handbag. Short of instituting an invasive and very workforce unfriendly search policy, keeping devices out of the company is virtually impossible. Wipe Master Hard Disk Sanitizers from Intelligent Computer Solutions The solution then, appears to be one of management. The first step here is to decide on what you can and cannot enforce. Remarkably, few companies actually realize how limited their powers actually are, especially with respect to current privacy and human rights legislation. For example, preventing employees from bringing their MP3 player to work and then using it during lunchtime would require draconian terms of employment that are almost certainly illegal. Companies that have tried similar experiments with regard to camera phones have found it hard to police and enforce. What you can do, however, is ensure that all members of staff are aware that their employment does not allow the connection of non-company devices to their computers or other peripherals. This means banning people from downloading their photos to that nice color printer. No swapping music with the person who sits next to you if that means connecting to the computer and using it as a transfer point. Administrators need to create security solutions that log the amount of data that a user downloads. It is already acceptable to search an employee’s hard disk for illegal files but few companies do this. Nightly sweeps of hardware to find MP3, WMA, JPG and other file extensions would seem a simple thing. Unfortunately, all of these formats have legitimate work uses and are often used by software packages for saving business files. Silicon Drive PC Card Solid State Disks - from Silicon Systems If you are to allow data to be transferred over removable media then you should consider how to secure it. There are several vendors with encryption solutions in the market. All of them have different advantages but whatever you choose should have a minimum set of features. Work with policy files to allow data to be locked after a given number of password attempts. Have a mechanism so that data can be encrypted once and then accessed where required without having to install software on the receiving computer. Be backed by an administration program that would allow for the recovery of lost passwords. Will work on a range of devices and removable media. Be simple to use, implement and manage.
The latter is all too often overlooked when deploying security solutions. There is a belief that security means complex, it doesn't. To ensure that people use a solution it must be simple, effective and deal with all situations. If you have to give encrypted files to someone who needs a copy of the software, then it becomes a case of either give them a license for the software or don't encrypt. Many people will opt for the latter. Files need to be self contained as an executable where the level of encryption is still high enough to thwart all but the most extensive brute force attack. There are products that fall into this category and they are worth finding and deploying in order to minimize the risks. One possible solution it to ensure that you encrypt everything that is downloaded from a computer onto any removable media. Your corporate data has never been so insecure. The ease with which is can now be removed from the office surpasses anything in history. There are approaches that you can use but they must encompass protection of content and system management simply banning devices will not work. Remember, we are now in a world where almost every month a new piece of regulation over data protection and access appears. If you don't sort this out now, they regulator will simply fine you extensive amounts of money and you'll still have the problem.
UNIVERSAL SERIAL BUS (USB)
Short for Universal Serial Bus, an external bus standard that supports data transfer rates of 12 Mbps. A single USB port can be used to connect up to 127 peripheral devices, such as mice, modems, and keyboards. USB also supports Plug-and-Play installation and hot plugging. Starting in 1996, a few computer manufacturers started including USB support in their new machines. It wasn't until the release of the best-selling iMac in 1998 that USB became widespread. It is expected to completely replace serial and parallel ports. The standard for USB version 2.0 was released in April 2000 and serves as an upgrade for USB 1.1. USB 2.0 (High-speed USB) provides additional bandwidth for multimedia and storage applications and has a data transmission speed 40 times faster than USB 1.1. To allow a smooth transition for both consumers and manufacturers, USB 2.0 has full forward and backward compatibility with original USB devices and works with cables and connectors made for original USB, too. Supporting three speed modes (1.5, 12 and 480 megabits per second), USB 2.0 supports low-bandwidth devices such as keyboards and mice, as well as highbandwidth ones like high-resolution Webcams, scanners, printers and high-capacity storage systems. The deployment of USB 2.0 has allowed PC industry leaders to forge ahead with the development of next-generation PC peripherals to complement existing high-performance PCs. The transmission speed of USB 2.0 also facilitates the development of next-generation PCs and applications. In addition to improving functionality and encouraging innovation, USB 2.0 increases the productivity of user applications and allows the user to run multiple PC applications at once or several high-performance peripherals simultaneously
How USB Ports Work:
Just about any computer that you buy today comes with one or more Universal Serial Bus connectors on the back. These USB connectors let you attach everything from mice to printers to your computer quickly and easily. The operating system supports USB as well, so the installation of the device drivers is quick and easy, too.
Compared to other ways of connecting devices to your computer (including parallel ports, serial ports and special cards that you install inside the computer's case), USB devices are incredibly simple! 1. Anyone who has been around computers for more than two or three years knows the problem that the Universal Serial Bus is trying to solve -- in the past, connecting devices to computers has been a real headache! 2. Printers connected to parallel printer ports, and most computers only came with one. Things like Zip drives, which need a high-speed connection into the computer, would use the parallel port as well, often with limited success and not much speed. 3. Modems used the serial port, but so did some printers and a variety of odd things like Palm Pilots and digital cameras. Most computers have at most two serial ports, and they are very slow in most cases. 4. Devices that needed faster connections came with their own cards, which had to fit in a card slot inside the computer's case. Unfortunately, the number of card slots is limited and you needed a Ph.D. to install the software for some of the cards. 5. The goal of USB is to end all of these headaches. The Universal Serial Bus gives you a single, standardized, easy-to-use way to connect up to 127 devices to a computer. Just about every peripheral made now comes in a USB version. A sample list of USB devices that you can buy today includes: Printers Scanners Mouse Joysticks Flight yokes Digital cameras Webcams Scientific data acquisition devices Modems Speakers Telephones Video phones Storage devices such as Zip drives Network connections
USB Features:
The Universal Serial Bus has the following features: The computer acts as the host. Up to 127 devices can connect to the host, either directly or by way of USB hubs. Individual USB cables can run as long as 5 meters; with hubs, devices can be up to 30 meters (six cables' worth) away from the host. With USB 2.,the bus has a maximum data rate of 480 megabits per second. A USB cable has two wires for power (+5 volts and ground) and a twisted pair of wires to carry the data. On the power wires, the computer can supply up to 500 milliamps of power at 5 volts. Low-power devices (such as mice) can draw their power directly from the bus. High-power devices (such as printers) have their own power supplies and draw
minimal power from the bus. Hubs can have their own power supplies to provide power to devices connected to the hub. USB devices are hot-swappable, meaning you can plug them into the bus and unplug them any time. Many USB devices can be put to sleep by the host computer when the computer enters a power-saving mode. The devices connected to a USB port rely on the USB cable to carry power and data.
Inside a USB cable: There are two wires for power -- +5 volts (red) and ground (brown) -- and a twisted pair (yellow and blue) of wires to carry the data. The cable is also shielded
The USB Process
When the host powers up, it queries all of the devices connected to the bus and assigns each one an address. This process is called enumeration -- devices are also enumerated when they connect to the bus. The host also finds out from each device what type of data transfer it wishes to perform: Interrupt - A device like a mouse or a keyboard, which will be sending very little data, would choose the interrupt mode. Bulk - A device like a printer, which receives data in one big packet, uses the bulk transfer mode. A block of data is sent to the printer (in 64-byte chunks) and verified to make sure it is correct. Isochronous - A streaming device (such as speakers) uses the isochronous mode. Data streams between the device and the host in real-time, and there is no error correction. The host can also send commands or query parameters with control packets. As devices are enumerated, the host is keeping track of the total bandwidth that all of the isochronous and interrupt devices are requesting. They can consume up to 90 percent of the 480 Mbps of bandwidth that is available. After 90 percent is used up, the host denies access to any other isochronous or interrupt devices. Control packets and packets for bulk transfers use any bandwidth left over (at least 10 percent). The Universal Serial Bus divides the available bandwidth into frames, and the host controls the frames. Frames contain 1,500 bytes, and a new frame starts every millisecond. During a frame, isochronous and interrupt devices get a slot so they are guaranteed the bandwidth they need. Bulk and control transfers use whatever space is left.
USB Flash Drive
A small, portable flash memory card that plugs into a computer’s USB port and functions as a portable hard drive. USB flash drives are touted as being easy-to-use as they are small enough to be carried in a pocket and can plug into any computer with a USB drive. USB flash drives have less storage capacity than an external hard
drive, but they are smaller and more durable because they do not contain any internal moving parts. USB flash drives also are called thumb drives, jump drives, pen drives, key drives, tokens, or simply USB drives. Intel® 82801DB or newer USB Controller OS Requirements
Operating System Windows* XP Windows* 2000 Windows* 98SE/Me Windows* 98 (Retail)
USB 2.0 requirements USB 2.0 drivers are provided in Service Pack 1 †(SP1) for Windows XP, which is available through Windows Update*. † USB 2.0 drivers are available through Windows Update †or Service Pack 4. USB 2.0 drivers are available on the Intel developer site. Developers and OEMs should contact Orange Ware. †For end-users, if your device does not ship with Windows 98 drivers, contact your device or system manufacturer. If USB 2.0 drivers are not available, your device will operate at USB 1.1 speeds USB 2.0 support is available in kernel 2.4.19 †or later development kernels, or in the 2.4.19 or later production kernel.
Linux*
Memory cards in video game consoles
Many video game consoles have used proprietary solid-state memory cards to store data, especially since games started being distributed in read-only optical discs. The sizes in parenthesis are those of the official cards. Microsoft Xbox line: Xbox Memory Unit (8MB) Xbox 360 Memory Unit (64MB, 256MB, and 512MB versions) Nintendo line: Nintendo 64 Controller Pak (256 KB, divided in 123 pages) Nintendo Game Cube Memory Card (59- (4 Mib/512 KiB), 251- (16 Mib/2 MiB) and 1019-block (64 Mib/8 MiB) versions) This memory is simply a modified SD card. Wii Nintendo Game Cube Memory Card compatible (see above) and Secure Digital card compatible Sega Dreamcast Visual Memory Unit (VMU) (128 KB divided in 200 blocks) Sega Saturn memory unit can hold 20 blocks of save games. Sony PlayStation line: PlayStation Memory Card (1 Mb/128 KB divided in 15 blocks) The Pocket Station can act as PlayStation Memory Card PlayStation 2 Memory Card (called the "Memory Card (8MB)(For PlayStation(r) 2(r))" onscreen) The PlayStation Portable uses Memory Stick Duo. The PlayStation 3 is compatible with Compact Flash, Secure Digital, and Memory Stick PRO. GP2X GNU/Linux based portable games console uses SD/MMC.
PRICES OF Some Removable Storage Media in Pakistani Currency
Kingston Data Traveler (512 MB) USB 2.0 Flash Drive It’s offers from Rs-550 to Rs-650/Kingston Data Traveler (1 GB) USB 2.0 Flash Drive It’s offers from Rs-800 to Rs-900/Kingston Data Traveler (2 GB) USB 2.0 Flash Drive It’s offers from Rs-1400 to Rs-1500/Kingston Data Traveler (4 GB) USB 2.0 Flash Drive It’s offers from Rs-2800 to Rs-3200/Normal CD’s and DVD’s It’s offers from Rs-30 to Rs-100/Floppy Disk It’s offers from Rs-15 to Rs-25/Memory Card of Different Cell phones It’s offers from Rs-550 to Rs-2500/-
CONCLUSION:
Removable storage media refers to CD's, DVD's, Floppy discs, USB drives. Nonremovable storage media refers to RAM, and Hard Drives. So where the storage media's are found depends upon which you are 'talking' about; but generally nonremovable inside the computer, removable outside of the computer. It’s very Much faster than transferring information from one personal computer to another via CD, floppy or another removable storage media. Removable storage media are very useful thing in this modern era.