An Educator's Guide to School Networks
 This is a great chapter by chapter formatted guide to networks including definitions, protocol, and hardware.

A Guide to Networking for K-12 Schools
Here you will find layouts, advantages of networking articles, and designing/planning a network ideas.

The consortium for School Networking
Here is a website designed specifically for technology leaders in schools.  Search topics include leadership development, advocacy, and emerging technologies.

Another Guide to K-12 Networking
This is a neatly organized site containing useful information on networking standards and common components and practices of networking.

Northwest Educational Technology Consortium
This program was established for the Northwest, including Montana, to help states integrate technologies.

Back

Back

Peer to Peer Networks-This is the simplest network where each client hs its own storage area, which might be shared with other clients.  There is no central storage for this type of network.

Client to Server Networks- This is the most common type of network.  These have storage devices on the network for shared use, normally called the file server.

LAN-Local Area Network
This is a network in which all clients share a common infrastructure and are usually located within the same building.

WAN-Wide Area Network
This is a network that spans a larger geographic area, usually comprised of two or more LANS.

Topology
The topology defines the different shapes a network can hold.  There are three main types of topology:

The Star Topology-
The star topology for a local area network looks like a star.  All network wiring runs from the client to the central hub in the middle.
 

Star topology
 

The Ring Topology-
This ring topology connects computers in a continuous loop
Ring topology

The BUS Topology-
This form is the oldest type of topology used where the network clients are strung along one single cable.

BUS topology
 

graphics taken from http:///www.netc.org/
Back

Protocol
A protocol is a standard for how devices communicate.  They are broken down into specific layers for different purposes.  The internet uses a group of protocols called a protocol suite.  For example, a common protocol suite is TCP/IP.
 

Fast Ethernet.
This is a new enhancement of Ethernet that runs at speeds of 100 Mbps, ten times the rate of original Ethernet. Known also as 100baseT, it requires that the wiring it runs over be category 5 (cat 5) wiring, a higher quality than the cat 3 used by normal Ethernet. The equipment needed to use Fast Ethernet is also more expensive than normal Ethernet, and although the prices are dropping, it is most likely too expensive for schools to install initially. Like 10baseT, it connects as a star topology and has a 100 meter maximum length restriction. This allows a district using cat 5 wiring to begin with 10baseT and later upgrade to 100baseT without replacing the wiring.

information taken from http://devius.cs.uiuc.edu/schools/bl-thesis/toc.doc.html

Back

Wireless technology
Uses one of two methods of communication, either lasers or microwaves. Laser technology offers higher speeds, but shorter ranges of only a few hundred meters. A more significant problem is that most lasers operate in the infrared spectrum and most conditions that block visible light such as rain, fog, or any other physical obstruction also block the laser.
 

Cable TV
Is an alternative to the phone company that is emerging. It allows a district to provide WAN connectivity using the cable tv wiring. Although still a new technology, it promises to offer high speeds and low costs. However, several technical problems need solutions. These are due to the current implementations of cable tv systems that send the same signal from a central office to many destinations.
 
 

Satellite
For districts located in remote areas, where other technologies are prohibitively expensive or unavailable, a satellite connection is a viable alternative. With this technology, a district buys a satellite dish and the necessary hardware needed to connect it to a network. A building then has a 56 Kbps downlink connection. As in the hybrid cable tv solution, satellite is an asymmetric solution and the uplink rate is only 9.6 Kbps.

Dialin Service
A district will need to make a decision regarding the installation of a dialin pool of modems connected to the district WAN. These modems could be for staff and student dialup access to the district WAN and/or to the Internet. This may seem like a good service to provide to the district. However, with most phone local and long distance phone companies offering this service for only about $20/month, it is not a service most districts should consider installing. It can easily become an expense and management problem. As more people begin to use the dialin service, a large percentage of the modems will show a significant increase in their use. A district would then need to buy additional modems to provide more dialin connections. A district could spend the money used for the modems and phone lines elsewhere with better gains to a district.

information and graph taken from http://devius.cs.uiuc.edu/

Back

Repeaters-Repeaters are the most basic type of active network equipment. They operate solely at the physical layer, receiving a signal on one port, or connection, and rebroadcasting it on all of its other ports. They can extend a network beyond the limits imposed by the wiring by boosting the signal level.

Hub-Hubs are multiport repeaters which usually come with a number of ports in multiples of twelve.  These ports allow the network to support a number of workstations.  The hubs connect either in a stackable or chassis system.

Bridge-Bridges operate at a higher level than repeaters, working at the data link layer and looking at the actual packets that are on the network. When they receive a packet, they store the entire packet in memory, verify its correctness, and retransmit it on the correct port. This allows them to connect different types of Ethernet networks together such as a 10baseT and a coax network.

Router-Routers operate at the network level. They receive a packet, view its destination, and determine if the packet is destined for a network that is directly connected to the router or if it is destined for a network further away. If it is the first it sends the packet to the correct port. If it is the latter, it sends the packet to the next router along the path to the packet's final destination.

NICs-The network interface card (NIC) is an add-on board that serves as the connection between the client computer and the network infrastructure. In other words, to hook all your computers together, a special electronic circuit card called a NIC goes inside each computer.

Cables
1.  Unshielded twisted pair-Otherwise known as a UTP wire, this type of wiring has been used in the past by telephone companies to attach  phones for local service.  Now it is used for voice applications and data-networking.
2.  Fiber Optic Cables-There are two types of fiber-optic cables: single and multimode.  Singlemode has a smaller core, and multimode has a larger diameter core; it is also more cost effective.
3.  Coaxil Cable-This is the most commonly used cable that has several layers of material surrounding a common axis.  It is used for video distribution.
4.  Wireless- Becoming more and more popular, the wireless cables have special applications in interbuilding communication and are most commonly used on campuses and district networks.

I think the wireless cable, although more expensive, would be the most appropriate in a school setting.  With technology on the rise and schools building on to their computer labs more often, the wireless cable would be the easiest to work with.

Back

Types of School Computer Networks
-All new networks installed in schools today are using the ethernet networks.

Types of Network Cable
-The recommended school standard in network cabling is the unshielded twisted pair or UTP.  Wireless networking is an alternate means of connecting one site to another using radio transmission.  This is a good option for sites which are difficult to cable due to their layout.

Intranet
-No, this is not the internet, but the intranet.  The term "intranet" describes an internal computer network which uses tools and protocols.  In other words, a student can feel like their searching the net, but not actually be live on the web.

Back