mid lec 5 cont1 networks
TRANSCRIPT
-
8/8/2019 Mid Lec 5 Cont1 Networks
1/33
NETWORK
Are multiple computers linked together to make simultaneousinformation sharing and exchange by multiple users. Computer
network makes it possible for its connected users to share tools,
resources and information. Resources include data, printers, internet
servers and software applications.
3 Basic Network Categories
1. Local Area Network (LAN)
2. Metropolitan Area Network (MAN)
3. Wide Area Network (WAN)
-
8/8/2019 Mid Lec 5 Cont1 Networks
2/33
NETWORK
1. Local Area Network
(LAN)
The smallest of the 3
network types
Consists of PCs
connected together
within a limited area
(same building, floor or
department)
Good for small to
medium businesses
-
8/8/2019 Mid Lec 5 Cont1 Networks
3/33
-
8/8/2019 Mid Lec 5 Cont1 Networks
4/33
NETWORK
2. Metropolitan Area
Network (MAN)
A network that spans
no more than 50 miles.It is designed to
connect LANs spanning
a town or city
-
8/8/2019 Mid Lec 5 Cont1 Networks
5/33
-
8/8/2019 Mid Lec 5 Cont1 Networks
6/33
NETWORK
3. Wide Area Network
(WAN)
Used to distribute
information thousand ofmiles among thousand
of users.
A WAN spans cities to
countries and even
continents
WANs can beconnected to existing
networks to form an
inter-network (internet)
-
8/8/2019 Mid Lec 5 Cont1 Networks
7/33
-
8/8/2019 Mid Lec 5 Cont1 Networks
8/33
Network Terms
Network Server a powerful computer whose sole purpose is to servenetwork clients. Servers run network controlling software and provideworkstations with requested resources.
-
8/8/2019 Mid Lec 5 Cont1 Networks
9/33
Hosts any computer whether mainframe, server or even a PC that acts
as an information source on a network. Essentially, any computer that
has an TCP/IP network address can be a host. Even a workstation can
be a host because it can act as a network information source.
-
8/8/2019 Mid Lec 5 Cont1 Networks
10/33
Peers any computer sharing the same protocol layer with another
computer. When two computers share resources, security levels and
user group, they are considered peers.
-
8/8/2019 Mid Lec 5 Cont1 Networks
11/33
Workstation is any network computer that connects to and requests
resources from a network
-
8/8/2019 Mid Lec 5 Cont1 Networks
12/33
Protocol refers to the specific standards governing the sending ands
receiving of data. Data transmission system follow predetermined rules
so data travels in universally accepted manner, because there are
different computer languages, protocols have been developed.
-
8/8/2019 Mid Lec 5 Cont1 Networks
13/33
2 Types of Network Architecture
1. Peer to Peer no
centralized computer oversees
the networks, no server, and
computers simply connect with
each other in a workgroup toshare files, printers and
Internet access
-
8/8/2019 Mid Lec 5 Cont1 Networks
14/33
-
8/8/2019 Mid Lec 5 Cont1 Networks
15/33
2 Types of Network Architecture
Client / Server use a
network OS to manage the
entire network. There is
usually a Domain Controller,
which all of the computers logon to. WSs requests
information- a file, for example-
from a server. The server
provides the requested
information. This server can
provide various services,including centrally routed
Internet Access, mail, file
sharing and printer access.
-
8/8/2019 Mid Lec 5 Cont1 Networks
16/33
-
8/8/2019 Mid Lec 5 Cont1 Networks
17/33
Network Media any material that transport data in any way orform. When data is sent over a network, it travels through wires,
cables or cords. The physical means through which a network datatravels is called media
RJ45 CONNECTOR
-
8/8/2019 Mid Lec 5 Cont1 Networks
18/33
1. UTP (Unshielded Twisted Pair) the least expensive and mostpopular network media.
Advantage: Special coating that shrinks in high fire temperature
eliminating toxic fumes Disadvantage: lack of insulation, which makes the cable susceptible
to electrical interference
-
8/8/2019 Mid Lec 5 Cont1 Networks
19/33
2. STP (Shielded Twisted Pair) is twisted, plastic coated, sheath-wrappedcopper wire. The main difference of UTP and STP is the STPs aluminum orpolyester shielding surrounding individual wires allowing STP to reduce oreliminate interference
-
8/8/2019 Mid Lec 5 Cont1 Networks
20/33
3. Fiber Optic are thin, glass strand that carry light waves and are wrapped by an
outer, protective sheath. Interpreted by computer as data, the light waves in a
fiber optic can travel great distances and deliver vast amounts of data. Fiber optic
cabling systems are extremely powerful and efficient but quite expensive
-
8/8/2019 Mid Lec 5 Cont1 Networks
21/33
4. Coaxial cable commonly used by cable TV. A center cable is insulatedby plastic or foam, wrapped in a copper mesh wire and sheathed in aplastic or rubber jacket. Coaxial cable is relatively inexpensive to produceand install.
-
8/8/2019 Mid Lec 5 Cont1 Networks
22/33
Network Hardware
1. Network Interface Card (NIC) a printed circuit board, an adapter
that plugs into the computers motherboard when connected with a
network cable, provides a physical link between your computer andthe network. Its main function is to convert computer data into cable-
transmittable data, and provide a connection to network media
-
8/8/2019 Mid Lec 5 Cont1 Networks
23/33
2. Network Hub a hardware device that all PCs on a network are
connected to by cabling. The hub manages receiving and
transmitting data from network devices. It allows data to flow on and
off the network between printers, computers and other devices bysharing the lanes of traffic
-
8/8/2019 Mid Lec 5 Cont1 Networks
24/33
3. Wireless Hub it works by converting network signals to radiofrequencies and back to network signals at the receiving computer
-
8/8/2019 Mid Lec 5 Cont1 Networks
25/33
Kinds ofHUBS
Standalone Hub are single products with a number of ports. The
least expensive kinds of hub. Typically with fewer than 12 users per
LAN
-
8/8/2019 Mid Lec 5 Cont1 Networks
26/33
Stackable Hubs work just like standalone hubs, except that several
of them can be stacked (connected) together. When they are
connected together, they act like a modular hub because they can
be managed as a single unit
-
8/8/2019 Mid Lec 5 Cont1 Networks
27/33
ModularHubs popular in networks because they are easily expandedand always have a management option. Purchased as a chassis or cardcage with several card slots, each of which accepts a communicationcard or module. Each module acts like a standalone hub.
-
8/8/2019 Mid Lec 5 Cont1 Networks
28/33
3 Basic HUB Types
1. Passive Hub simply connects various cables
2. Active Hub amplify or boost signals3. Intelligent Hub select which path a specific signal will travel
Active Hub
Passive Hub
Intelligent Hub
-
8/8/2019 Mid Lec 5 Cont1 Networks
29/33
4. Repeater a device that strengthen signals and allow them to stay clear
over longer distance
2 Basic Types of Repeater
1. Amplifiers strengthen an incoming signal to make the signalstronger and more powerful, unfortunately the accompanying noise is
also amplified
-
8/8/2019 Mid Lec 5 Cont1 Networks
30/33
2. Signal Generators a device that work by receiving and rebuilding
signals, then re-transmitting the signal with fresh power
-
8/8/2019 Mid Lec 5 Cont1 Networks
31/33
Network Bridge divides network into smaller, more manageable sections
helping reduce network traffic. Data signals arriving at a bridge contain
information about their destinations. The network bridge allows only specific
information to travel over certain paths. When a signal arriving at a bridge does
not posses the appropriate address it is filtered out completely.
-
8/8/2019 Mid Lec 5 Cont1 Networks
32/33
Network Switch makes asimple do / dont decision onwhich packets to send acrosstwo segments they connect. It
helps determine how datamoves over very largenetworks. It works like astoplight at a busy intersection.It allows data to travel in its ownlane of traffic.
3 Types of Network Switches1. Circuit Switch establish asingle, direct data route
2. Message Switch storedata, forwarding the informationwhen possible
3. Packet Switch combinecircuit and message switchingtechnology dividing longmessages into smaller onescalled Packages
-
8/8/2019 Mid Lec 5 Cont1 Networks
33/33
Router a device that forwards data packets between Local or Wide
Area Network groups. Using routing tables and protocols, routers
read a signals network address and decides its most expedient
route