Chapter 6 Study Questions
1. Why should I care about networks?
Collaboration occurs when two or more people work together to achieve a
common goal, result or product. When collaboration is effective, the results of
the group are greater than those that could be produced by any of the
individuals working alone. It involves coordination and communication, and
often the use of computer networks.
The effectiveness of a collaborative effort is driven by 4 critical factors:
1) Communication skills & culture
2) Communication systems
3) Content management
4) Workflow control
1: Communication skills and culture are often the key to effective
collaborative effort. The ability to be part of a group and to give and receive
critical feedback is particularly important for employers
2: The availability of effective communication systems depends on the
network technology available in an organization.
3: Content management - when multiple users are contributing and
changing documents, schedules, task lists, assignments, etc., one user’s work
might interfere with another’s. Users need to manage content so this kind of
conflict does not occur.
4: A workflow is a process or procedure by which content is created,
edited, used, and disposed. The concept of workflow is very close to the concept
of a business process—but workflow focuses on delivering a good or service
internally to other employees in the organization, whereas a business process
focuses on delivering a good or service externally to a customer.
Network externality: the larger the number of people using a network, the more
valuable that network becomes. When networks are first started, people often
look for the critical mass. This is the point at which the value of being part of the
network is larger than the cost of being on it. Once networks hit critical mass,
they usually grow at a faster rate.
There are limits to network growth. As a network continues to gain users, there
may be problems with congestion or the market may become saturated. When this occurs, the rate of growth diminishes and then either flattens or becomes
2. What is a computer network?
A computer network is a collection of computers that transmit and/or receive
electronic signals through transmission media. The transmission media might be
physical media, or wireless media transmitting light, or radio frequencies.
A local area network (LAN) connects computers within a relatively small, single
geographic location. The distinguishing characteristic of a LAN is that it is in a
single location. An organization can place communications lines wherever it
wants, because all lines reside on its premises.
Wide area networks (WAN) connect computers at different geographic
locations. An organization must contract with a communications vendor that is
licensed by the government and already has lines or has the authority to run new
lines between the two cities.
An internet is a network of networks. Internets connect LANs, WANs, and other
internets. The most famous internet is “the Internet,” the collection of networks
that you use when you send email or access a website.
The networks that comprise an internet use a large variety of communication
methods and conventions, and data must flow seamlessly across them.
A protocol is a set of rules that two communicating devices follow. For two
devices to communicate, they must both use the same protocol.
3. What are the components of a LAN?
A local area network (LAN) is a group of computers connected together on a
single company site. Usually the computers are located within a kilometer or so
of each other, although longer distances are possible. The key distinction is that
all the computers are located on property controlled by the company that
operates the LAN.
A switch is a special-purpose computer that receives and transmits messages on
Each device on a LAN (computer, printer, etc.) has a hardware component called
a network interface card (NIC) that connects the device’s circuitry to the network cable. The NIC works with programs with each device to implement the
protocols necessary for communication.
On older machines, the NIC is a card that fits into an expansion slot. Newer
machines have an onboard NIC, which is a NIC that is built into the computer.
Each NIC has a unique identifier, which is called the MAC (media access control)
address. The computers, printers, switches, and other devices on a LAN are
connected using one of two media. Most connections are made using
unshielded twisted pair (UTP) cable. A device called an RJ-45 connector is used
to connect the UTP cable into NIC devices on the LAN.
Some larger LANs use more than one switch. Typically, in a building with several
floors, a switch is placed on each floor, and the computers on that floor are
connected to the switch with UTP cable. A main switch connects the switches on
The connections between switches can use UTP cable, but if they carry a lot of
traffic or are far apart, optical fibre cables may replace UTP cable. The signals on
such cables are light rays, and are reflected inside the glass core of the optical
fibre cable. The core is surrounded by a cladding to contain the light signals, and
the cladding, in turn, is wrapped with an outer layer to protect it.
For a LAN to work, all devices on the LAN must use the same protocol. Today,
the world’s most popular protocol for LANs is the IEEE 802.