Transcript Local area network - Quality Technical Writing

Networks: Communicating &
Sharing Resources
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Objectives
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Understand basic networking concepts.
Discuss the advantages and
disadvantages of networks.
Distinguish between peer-to-peer
(P2P) and client/server local area
networks (LANs).
Define topology and understand how
the three LAN topologies differ.
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Objectives
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Explain the importance of network
protocols.
Name the most widely used LAN
protocol and its versions.
Identify the special components of a
wide area network (WAN) that
differentiate it from a LAN.
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Objectives
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Contrast circuit-switching and packetswitching networks and explain their
respective strengths and weaknesses.
Identify the options, components,
configuration, and maintenance of a
home area network (HAN).
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Network Fundamentals
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A network links multiple computer
systems to enable them to share data
and resources.
Categories of computer networks for
business and organizations:
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Local area network (LAN)
Wide area network (WAN)
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Network Fundamentals
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Network Fundamentals
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LAN
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Uses cables, radio waves, or infrared signals
Links computers in a limited geographic area
WAN
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Uses long-distance transmission media
Links computer systems a few miles or
thousands of miles apart
The Internet is the largest WAN
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Network Fundamentals
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Communication devices
convert data into signals
to travel over a medium.
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Computers
Modems
Routers
Switches
Network interface cards
(NICs)
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Network Fundamentals
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A node is any device connected to a
network.
Network interface card (NIC)
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An expansion board or adapter that
provides a connection between the
computer and the network
Notebook computers have wireless NICs
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Network Fundamentals
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Routers
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Connect two or more networks
Determine the best route to transmit data
Switches
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Filter and forward data between nodes
Are similar to routers but work within a
single network
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Network Fundamentals
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Wireless access
point (WAP)
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Receives and transmits
radio signals
Joins wireless nodes to a
wired network
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Network Fundamentals
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File server
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High-speed computer that provides
program and data files to network users
Contains the network operating system
(NOS)
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File directories for file and resource location
Computerized software update distribution
Internet services support
Protection of services and data
Access to connected hardware by authorized
users
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Advantages &
Disadvantages of Networking
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Networking
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Advantages
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Hardware cost reduction
Sharing of information, data, and applications
Data management centralization
Linking of people
Disadvantages
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Loss of autonomy
Lack of privacy
Security threats
Loss of productivity
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Local Area Networks
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Peer-to-peer (P2P) networks
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Share files without a file server
Are easy to set up
Are best used for home or small offices
with no more than 10 computers
Do not require a network operating system
Can be slow if there are too many users
Security is not strong
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Local Area Networks
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Peer-to-peer (P2P) networks
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Local Area Networks
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Client/server networks
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Made up of one or more file servers and
clients (any type of computer)
Client software enables requests to be sent
to the server
Wired or wireless connections
Do not slow down with heavy use
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Local Area Networks
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Virtual private network
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Operates over the Internet
Is accessible by authorized users for quick
access to corporate information
Uses secure, encrypted connections and
special software
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Local Area Networks
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LAN topologies
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Network topology is the physical
design of a LAN.
Topology resolves contention, the
conflict that occurs when two or more
computers on the network attempt to
transmit at the same time.
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Local Area Networks
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LAN topologies
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Bus topology
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Star topology
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Practical for home or small office
One node transmits at a time
For office buildings, computer labs, and WANs
Easy to add users
Ring topology
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For a division of a company or one floor
Not in common use today
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Local Area Networks
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Local Area Networks
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Local Area Networks
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Local Area Networks
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LAN protocols
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Protocols are the standards used by
networks to permit communication
between network-connected devices.
A network’s protocol suite contains the
protocols of the network and specifies its
network architecture, or how the network
works.
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Local Area Networks
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LAN protocols
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Network layers divide architecture for
separate treatment.
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Each network layer can operate and be
governed by its own protocols.
The vertical arrangement of network layers is
called a protocol stack.
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Local Area Networks
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LAN protocols
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LAN technologies
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Ethernet is the most-used LAN protocol.
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The most popular versions are Ethernet star
networks, which use twisted-pair wiring and switches.
Wi-Fi
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Uses radio waves to provide a wireless LAN
standard at Ethernet speeds
Needs a central access point, which could be a
wireless router
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Wide Area Networks
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Point of presence (POP)
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WAN connection point used to obtain
access to the WAN
Wired or wireless
Backbones
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High-capacity WAN transmission lines
gigaPoP (gigabits per second point of
presence) transfers data exceeding 1 Gbps
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Wide Area Networks
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WAN protocols
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Internet protocols
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Transmission Control Protocol (TCP)
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Internet Protocol (IP)
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Defines how Internet-connected computers can
exchange, control, and confirm messages
Provides a distinct identification to any computer
connected to the Internet: the IP address
TCP/IP
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Together, they define how the Internet works.
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Wide Area Networks
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WAN protocols
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Circuit switching
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Used by the public switched telephone network
to send data over a physical end-to-end circuit
Provides a direct connection between devices
Packet switching
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Used for computer communication
Divides and sends outgoing messages as packets,
which are reassembled upon receipt
More efficient and less expensive than circuit
switching
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Wide Area Networks
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Wide Area Networks
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Wide Area Networks
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Wide Area Networks
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Wide Area Networks
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WAN applications: E-mail,
conferencing, document exchange,
remote database access
 LAN to LAN Connections
 Transaction Acquisition
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Home Networks
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Wired Home Networks
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Ethernet networks link computers with a
switch or router.
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Home Networks
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Wireless Home Networks
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Wi-Fi is the wireless standard.
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Uses radio signals
Communicates through network access points
Needs wireless adapter or router
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Home Networks
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Setting up a home network
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Planning
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Select technology
Purchase equipment and firewall software
Configuring a wired network
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Connect each computer to the router
Plug printer, scanner, etc., into a computer
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Home Networks
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Setting up a home network
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Configuring a wireless network
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Connect each node to wireless router with a
wireless adapter
Connect DSL or cable modem to wireless router
Maintenance and support
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Minimal maintenance required
Unplug power source from router and other
peripherals and restart computer to correct
problems
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Home Networks
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Future of home networking
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Control household appliances.
Protect homes with security systems.
Manage home network events through
central control units in new homes.
Utilize wireless systems.
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Summary
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Computer networks of two or more
linked computers share resources and
exchange data.
The two main types of networks are
local area networks (LANs) and wide
area networks (WANs).
There are advantages and
disadvantages to using a computer
network.
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Summary
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Two main categories of LANs are peerto-peer (P2P) and client/server.
Topologies of a LAN include the bus
topology, the ring topology, and the
star topology.
Protocols define the manner in which
network devices communicate.
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Summary
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The Ethernet is the most popular LAN
protocol.
Distinguishing components of a WAN,
as compared with a LAN, are its point
of presence (POP) and backbones.
WAN connections may be made
through analog telephone calls or
digital hookups.
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Summary
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The technologies on which WAN
protocols are based use either circuit
switching (PSTN) or packet switching
(the Internet).
Wired home networks use Ethernet
cable, and wireless home networks
rely on Wi-Fi radio signals.
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