The article chapter: The Internet: Computer Network Hierarchy elaborates how when you connect to the Internet, your computer becomes part of a network.
“Every computer that is connected to the Internet is part of a network, even the one in our home, for example, you may use a modem and dial a local number to connect to an Internet Service Provider (ISP). At work, you may be part of a local area network (LAN), but you most likely still connect to the Internet using an ISP that your company has contracted with. When you connect to your ISP, you become part of their network. The ISP may then connect to a larger network and become part of their network. The Internet is simply a network of networks.
Most large communications companies have their own dedicated backbones connecting various regions. In each region, the company has a Point of Presence (POP). The POP is a place for local users to access the company's network, often through a local phone number or dedicated line. The amazing thing here is that there is no overall controlling network. Instead, there are several high-level networks connecting to each other through Network Access Points or NAPs.”
The article chapter: Internet Network example concludes that “In the real Internet, dozens of large Internet providers interconnect at NAPs in various cities, and trillions of bytes of data flow between the individual networks at these points. The Internet is a collection of huge corporate networks that agree to all intercommunicate with each other at the NAPs. In this way, every computer on the Internet connects to every other.”
The article chapter: Function of an Internet router illustrates that “Routers are specialized computers that send your messages and those of every other Internet user speeding to their destinations along thousands of pathways. A router has two separate, but related, jobs:
· It ensures that information doesn't go where it's not needed. This is crucial for keeping large volumes of data from clogging the connections of "innocent bystanders."
· It makes sure that information does make it to the intended destination.”
The article chapter: Internet Backbone elaborates that “Backbones are typically fiber optic trunk lines. The trunk line has multiple fiber optic cables combined together to increase the capacity. Fiber optic cables are designated OC for optical carrier, such as OC-3, OC-12 or OC-48. An OC-3 line is capable of transmitting 155 Mbps while an OC-48 can transmit 2,488 Mbps (2.488 Gbps). Compare that to a typical 56K modem transmitting 56,000 bps and you see just how fast a modern backbone is.
Today there are many companies that operate their own high-capacity backbones, and all of them interconnect at various NAPs around the world. In this way, everyone on the Internet, no matter where they are and what company they use, is able to talk to everyone else on the planet. The entire Internet is a gigantic, sprawling agreement between companies to intercommunicate freely.”
The article chapter: Internet Protocol: IP address elaborates that “Every machine on the Internet has a unique identifying number, called an IP Address. The IP stands for Internet Protocol, which is the language that computers use to communicate over the Internet. A protocol is the pre-defined way that someone who wants to use a service talks with that service. The "someone" could be a person, but more often it is a computer program like a Web browser.
A typical IP address looks like this:
216.27.61.137
To make it easier for us humans to remember, IP addresses are normally expressed in decimal format as a dotted decimal number like the one above. But computers communicate in binary form. Look at the same IP address in binary:
11011000.00011011.00111101.10001001”
1) Andrew K. Pace. Dismantling Integrated Library Systems Library Journal, vol 129 Issue 2, p34-36. 2/1/2004
This article elaborates that many expect in future ILS new modules will communicate with old ones, products from different vendors will work together, and a suite of existing standards will make distributed systems seem transparently whole. But in an ironic twist, most of the touted interoperability is between a vendor's own modules (sometimes) or between a library's homegrown solutions and its own ILS (sometimes). Today, interoperability in library automation is more myth than reality. Some of us wonder if we may lose more than we gain in this newly dismantled world. The article concludes that Librarians and vendors should work on developing interoperable library systems and suggests that the open source movement has demonstrated the value of open standards and protocols. Through XML, web services, OAI-PMH (Open Archives Initiative--Protocol for Metadata Harvesting), librarians believe they can create interoperability among systems, whether vendors' or their own. The article also suggests that vendors are already using standards and protocols to build logical relationships with course management vendors (Blackboard and WebCT), accounting and HR systems (PeopleSoft), and authentication tools (LDAP, EZProxy, and Shibboleth). If vendors can build interoperability with these systems, then they can become interoperable with each other and with local library systems. Finally, the article concludes that library vendors have two choices. They can continue to maintain large systems that use proprietary methods of interoperability and promise tight integration of services for their customers. Or, they can choose to dismantle their modules in such a way that librarians can reintegrate their systems through web services and standards, combining new with the old modules as well as the new with each other.
2) Sergey Brin and Larry Page: Inside the Google machine. This vedio casts Google co-founders Larry Page and Sergey Brin who talked about the peek inside the Google machine, sharing tidbits about international search patterns, the philanthropic Google Foundation, and the company's dedication to innovation and employee satisfaction. It also elaborates about some Google projects undertaken on 2004.
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