Week 6 reading notes

Local Area Network
(http://en.wikipedia.org/wiki/Local_Area_Network)

“A local area network (LAN) is a computer network covering a small physical area, like a home, office, or small group of buildings, such as a school, or an airport. The defining characteristics of LANs, in contrast to wide-area networks (WANs), include their usually higher data-transfer rates, smaller geographic place, and lack of a need for leased telecommunication lines.”

“Ethernet was developed at Xerox PARC in 1973–1975, and filed as U.S. Patent 4,063,220. In 1976, after the system was deployed at PARC, Metcalfe and Boggs published their seminal paper, "Ethernet: Distributed Packet-Switching For Local Computer Networks."
ARCNET was developed by Datapoint Corporation in 1976 and announced in 1977. It had the first commercial installation in December 1977 at Chase Manhattan Bank in New York.”

“The development and proliferation of CP/M-based personal computers from the late 1970s and then DOS-based personal computers from 1981 meant that a single site began to have dozens or even hundreds of computers. The initial attraction of networking these was generally to share disk space and laser printers, which were both very expensive at the time.”

- Novell NetWare – 1983-mid 90s
- Windows NT and Windows for Workgroups – mid 90s-onward

This article had useful information about LANs and what they were used for, what their history was, and examples of types of LANs that are used now and were used in the past.

Computer Network
(http://en.wikipedia.org/wiki/Computer_network)

“A computer network is a group of interconnected computers. Networks may be classified according to a wide variety of characteristics.”

“A computer network allows computers to communicate with many other and to share resources and information. The Advanced Research Projects Agency (ARPA) funded the design of the "Advanced Research Projects Agency Network" (ARPANET) for the United States Department of Defense. It was the first operational computer network in the world. Development of the network began in 1969, based on designs begun in the 1960s.”

“Computer networks can also be classified according to the hardware and software technology that is used to interconnect the individual devices in the network, such as Optical fiber, Ethernet, Wireless LAN, HomePNA, Power line communication or G.hn. Ethernet uses physical wiring to connect devices. Frequently deployed devices include hubs, switches, bridges and/or routers.”

“Wireless LAN technology is designed to connect devices without wiring. These devices use radio waves or infrared signals as a transmission medium.”

Wired Technologies
Twisted-Pair Wire
Coaxial Cable
Fiber Optics

Wireless Technologies
Terrestrial Microwave
Communications Satellites
Cellular and PCS Systems
Wireless LANs
Bluetooth
The Wireless Web

“Networks are often classified as Local Area Network (LAN), Wide Area Network (WAN), Metropolitan Area Network (MAN), Personal Area Network (PAN), Virtual Private Network (VPN), Campus Area Network (CAN), Storage Area Network (SAN), etc. depending on their scale, scope and purpose.”

“An Internetwork is the connection of two or more distinct computer networks or network segments via a common routing technology. The result is called an internetwork (often shortened to internet).”

“All networks are made up of basic hardware building blocks to interconnect network nodes, such as Network Interface Cards (NICs), Bridges, Hubs, Switches, and Routers.”

This article had more information on other types of networks besides LAN. It told a little bit about the history of computer networks (starting with ARPANET, the precursor to the Internet in the 1960s). it also talked about hardware and software different networks used and how they are used to classify different types of networks. It described different types of wired and wireless technologies used in different networks, and all of the different types of networks there are and how they are used. One thing I didn’t know that I thought was interesting was that the name “Internet” comes from the term “Internetwork”, which is the connection of two or more computer networks through a common routing technology. I’ve used the term “Internet” for so long that I never stopped to think where the name might actually come from, and what it all meant in simple terms.

YouTube – common types of computer networks
(http://www.youtube.com/watch?v=1dpgqDdfUjQ)

This short video basically talked about different types of networks that were explained in the Wikipedia article above. He talked about which networks were the most common and how they are used differently. He explained that the most common type of network is the Personal Area Network, which is basically things connected to a single computer, like a printer, copier, scanner, etc. I found PANs to be the most interesting, as I had never really thought about devices connected to a computer being considered a network themselves before. I guess when I think of the term “network” I think more of computers being connected to each other rather than devices being connected to a single computer.

Management of RFID in Libraries
Karen Coyle
(https://sremote.pitt.edu/,DanaInfo=ejournals.ebsco.com+Direct.asp?AccessToken=9I55X5D8X9MZKZRZDPXM5X9U4ZD98I4X5&Show=Object&msid=931959202)

“Briefly, the RF in RFID stands for “radio frequency”; the “ID” means “identifier.” The tag itself consists of a computer chip and an antenna, often printed on paper or some other flexible medium. The shortest metaphor is that RFID is like a barcode but is read with an electromagnetic field rather than by a laser beam.”

“In considering the introduction of any technology into the library we need to ask ourselves “why?” What is the motivation for libraries to embrace new technologies? The answer to this question may be fairly simple: libraries use new technologies because the conditions in the general environment that led to the development of the technology are also the conditions in which the library operates.”

“There is, however, a key difference to the library's inventory as compared to that of a warehouse or retail outlet. In the warehouse and retail supply chain, goods come in, and then they leave. Only occasionally do they return. The retail sector is looking at RFID as a “throw-away” technology that gets an item to a customer and then is discarded. Yet the per item cost of including an RFID tag is much more than the cost of printing a barcode on a package. In libraries, items are taken out and returned many times. This makes the library function an even better use of RFID than in retail because the same RFID tag is re-used many times.”

“Second only to circulation, libraries look to RFID as a security mechanism…. Although RFID can be used in library anti-theft systems, this does not mean that it is a highly secure technology…. The reason to use RFID for security is not because it is especially good for it, but because it is no worse than other security technologies.”

“This is an area where RFID can provide great advantages because the tags can be read while the books sit on the shelf. Not only does the cost of doing an inventory of the library go down, the odds of actually completing regular inventories goes up. This is one of those areas where a new technology will allow the library to do more rather than just doing the same functions with greater efficiency.”

This article had lots of information on RFIDs and how they are already used in other capacities, and how they can be used in libraries. She gives a good argument about why RFIDs can be very useful to libraries – they are more practical with libraries than with items of a warehouse or in retail, since a library’s resources are used multiple times compared to a retail item that is generally bought once and doesn’t come back. It also works as a security mechanism, alerting the library at any time to where an item is if it isn’t where it’s supposed to be. She notes that it might not be highly secure, as there are ways to remove it from a book or block the signal using mylar or aluminum, but it isn’t worse than any other type of security measure. It also is extremely useful when doing inventory, since with bar codes the books need to be opened and scanned, while with RFID technology they can stay on the shelf and be read without being moved.