Transcript A+ Chapter 16a Network Terminology_final

A+ Certification Guide
Chapter 16 (Part A)
Networking
Chapter 16 (Part A)
Objectives
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Network Models and Topologies
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The client/server and peer-to-peer networking models
Internet Connectivity Technologies
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How to install and make dial-up connections. Services such as
ISDN, DSL, cable, and satellite. LAN connectivity to the Internet.
Network Protocols
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Basics about Transmission Control Protocol/Internet Protocol
(TCP/IP)
TCP/IP Applications and Technologies
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The protocols, services, and ports used by TCP/IP
Network Tools
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Tools for cabling a network
Network Types
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Wired and wireless network technologies
Network Models
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Client/Server:
– Servers provide services to clients.
• Print server provides access to print device.
• Web server provides access to html files.
• Domain controller provides centralized security services.
– Ability to grow with organization.
– Centralized security, auditing, and network management.
Peer to Peer:
– Each workstation is independently managed.
• All security is contained on locally managed disk.
– Limited growth due to lack of manageability.
• File can be shared, but each folder on each machine must be
individually shared and controlled—time-consuming.
LANs and WANs
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Local Area Network (LAN)
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A group of computers and network-attached devices located in
the same building or at least on the same property
Wide Area Network (WAN)
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WANs connect LANs to each other.
Distance between local networks generally distinguishes LANs
from WANs.
WANs typically lease the use of third-party wires/equipment
from a provider to make connections.
• Data Communications Service Providers
– AT&T, Bellsouth, Sprint, and so on
Network Support Devices
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Hub
Bridge/Switch
Wireless Access Point
Router
Layer 3 Switch
Firewall
Network Attached Storage
Modem
Internet Appliance
VOIP Phone Systems
Network Topologies
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Bus
– Computers in a bus topology share a common cable. Connections are
made largely with coaxial 10BASE2 and 10BASE5 cables.
Star
– Computers in a star topology connect to a central switch (wired) or
access point (wireless).
– Used by 10BASE-T, 100BASE-T, and 1000BASE-T Ethernet networks
and by Wireless Ethernet when configured for infrastructure mode.
Ring
– Computers in a ring topology either connect as a physical ring (for
example, FDDI networks) or a logical ring (for example, Token Ring
networks).
Peer-to-Peer (Mesh)
– Computers in a peer-to-peer or mesh topology can connect directly to
every other computer.
– Used by computers with multiple network adapters, Wireless Ethernet
(Wi-Fi) when configured for peer-to-peer mode, and Bluetooth.
Internet Connectivity
Technologies
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Dial-up connectivity:
– Modems
– ISDN
Broadband
DSL
Satellite
Cellular
WiMAX
Trunk lines (T-1)
Dial-Up Connections
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Telephone Modems:
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Uses analog telephone connection by converting digital serial
data into sound wave-based analogy data
Bandwidth (speed) limited to 56Kbps
Can be internal or external
Can be installed as PC Card on a notebook computer
Follow usual ESD precautions when installing
ISDN (Integrated Services Digital Network):
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Also uses a modem and telephone line
Can transmit 128Kbps
Often used as backup line to a T-1 or faster connection
Broadband Internet Services
(DSL, Cable, and Satellite)
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Broadband Service:
– Uses a cable modem to convert broadband signaling to baseband
signaling (serial)
– Generally associated with cable TV providers
– Shared media with other local customers
– Advertised bandwidth of 2-10Mbps
• Sometime less, sometimes more
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DSL:
– Dedicated bandwidth
– Dependent on distance from phone company for quality of service
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Satellite:
– Requires a telephone for transmitting service requests
– Uses a dish antenna precisely focused on a satellite
DSL Modem Physical Setup
DSL Modem and Single PC
Topology
Cable Modem and Single PC
LANs and Internet Connectivity
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Allows more than one device to access Internet via a
single connection
– Requires
• Internet access device
– Cable modem
– DSL modem
• Router
– Forwards data packets from the Internet to the
local network and vice versa
– Can be a workstation set up with Internet
Connection Sharing (ICS)
LAN Connection to Internet
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The ISP equipment could be a DSL, cable modem, or even a T-1 connection.
Network Protocols
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Transmission Control Protocol/Internet Protocol (TCP/IP)
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Dominant networking protocol in the world
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Has been adopted by all manufacturers of networking devices
NetBIOS Extended User Interface (NetBEUI/NetBIOS)
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No network number in its structure
• Cannot be routed on an internetwork
• Useful only on a single broadcast domain
TCP/IP is the only practical protocol to know
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Transmission Control Protocol
• Verifies that the data delivery process is successful
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Internet Protocol.
• Ensures that data packets can be tagged with information
needed so as to be sent to specific networks and to
specific hosts on those networks
TCP/IP Applications and
Technologies—Terms to Know
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Internet Service Provider (ISP):
• Uses routers connected to dedicated high-speed
connection to the Internet.
• Customers use TCPIP to connect to service
provider.
– Hypertext Transfer Protocol (HTTP/HTTPS):
• Used by web browsers to interpret Internet
service requests through the URL line
– Secure Sockets Layers (SSL):
• Encryption used by HTTPS to secure data
– Transport Layer Security (TLS):
• Successor to SSL
TCP/IP Applications and
Technologies—Terms to Know
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Hypertext Markup Language (HTML):
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Code for how web pages are written
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Uses “tags" to separate data types, formats, and so on
File Transfer Protocol (FTP):
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Widely used to transfer files
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Can be used
• In a web browser
• From a command line
• From specially written FTP programs
Telnet:
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Unsecure method of remote access
TCP/IP Applications and
Technologies—Terms to Know
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Secure Shell (SSH):
– Encrypted replacement for telnet
Domain Name Server (DNS):
– Takes a web domain request and matches it to the
actual IP address needed to fulfill the request
– Part of a worldwide server system
– Top-level domains follow the dot “.”
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.com, .gov, .org, and so on
Like a software phone book of the Internet
TCP/IP Applications and
Technologies—Terms to Know
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Simple Mail Transport Protocol (SMTP)/Email:
– Uses a server to receive and notify clients of email:
• Protocols include SMPT, POP, and IMAP
– Email might be thought of as a streamlined way of
putting text in a remote machine’s folder “inbox.”
Simple Network Management Protocol (SNMP):
– Used to remotely monitor and manage network
devices.
Dynamic Host Configuration Protocol (DHCP)
– Used to automatically assign IP Addresses to
network nodes.
TCP/IP Technologies (continued)
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Remote Desktop
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Uses Remote Desktop Protocol (RDP) to allow remote access
to and control of the desktop GUI for purposes of technical
maintenance and troubleshooting
SMB
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Server Message Block provides access to file and printers to
multiple clients through authentication.
Lightweight Directory Access Protocol (LDAP)
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Microsoft uses this to create Directory Services (Active
Directory).
Ports
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16-bit long number assigned to map running
applications to the data generated by the application.
– Example of a data request to port 80 on a remote web
server:
• The remote web server sees the port 80 request.
• It knows that port 80 is the port that is being used
by the web server application.
• The web server application responds by retrieving
the data file (web page) and returning it to the
client.
• The requesting client receives the data and directs
it to the port being used by its web browser.
Common Protocols/Ports
Protocol
Port Used
FTP
21
SSH
22
Telnet
23
SMTP
2
DNS
53
HTTP
80
POP3
110
IMAP
143
HTTPS
443
RDP
3389
Cable and Connector Types
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Unshielded twisted-pair (UTP):
– 4 pairs of twisted 26-gauge wire
• Twists provide protection from crosstalk.
– Most common type (CAT5, CAT5e cables)
• See Table 16-6 for details.
– Uses RJ-45 connector
Shielded twisted-pair (STP):
– Has metal braid to protect against EMI
Ethernet Network Types
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Wired:
– 10Base-T
– 100Base-TX
– 1000Base-T
– Fiber-optic based, such as 1000Base FX
Wireless:
– 802.11a—5GHz
– 802.11b—2.4GHz
– 802.11g—2.4GHz
– 802.11n—2.4/5GHz
– Bluetooth—Used for Personal Area Networks
Unshielded Versus Shielded
Twisted-Pair Cable
UTP/STP Cabling Categories
Category
Network Type(s)
Supported
Supported
Speeds
Cable Type, Notes
UTP; obsolete; replace
3
10BASE-T Ethernet
Up to 10 Mbps
with Cat5, Cat5e, or
Cat6.
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Token ring
Up to 16 Mbps
Shielded twisted pair
5
10BASE-T, 100BASE-T
Up to 100 Mbps
UTP, STP; four-wire
5e
10BASE-T, 100BASE-T, Up to 1000
1000BASE-T
Mbps
(STP); one-wire pair
pairs
Enhanced version of
Cat5; available in UTP,
STP; four-wire pairs
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10BASE-T, 100BASE-T, Up to 1000
1000BASE-T
Mbps
Handles higher
frequencies than
Cat5/5e
Ethernet Network Types
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Infrared:
– Used for short range—laptop to laptop
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Cellular:
– Digital phone networks
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Voice over IP (VOIP):
– Digital phone service
– Uses Internet provider
– Requires specialized knowledge to set up
 Bluetooth:
– Wireless signal for Personal Area Networks (PAN)
Cable and Connector Types
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Fiberoptic:
– Single Mode—For long distances; single frequency
– Multi-Mode—Shorter distances; multiple frequencies
– Subscriber Connector (SC)—Square tip.
– Straight Tip (ST)—Round tip
– Fiber Connector (FC)—Round connector
Coaxial:
– Was used in bus topology; now used by cable TV
– RG59 and RG5 with BNC connectors
– May require a transceiver to connect to a switch or
host
Insulation and Fire Standards
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Wire insulation:
– Polyvinyl Chloride (PVC):
• Durable but poisonous when burned
– Plenum cable:
• Produces less toxic smoke when burned
• Usually required in suspended ceilings
Networking Tools
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Wire Scissors
Wire Stripper
Crimper
Punchdown tool
LAN Wire Tester
Continuity Tester
Tone Generator/Probe
Troubleshooting
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Check cable connectors for damage.
Check cable for damage to insulation.
Check link lights on back of PC or switch.
Verify that the correct impedance cable is being
used.
What Have You Learned?
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What type of cable should be purchased when
several light frequencies are intended to be used?
What is the practical limit of CAT5 cable?
Why is the wire twisted in a CAT5 cable?
What advantage does SSH offer over Telnet?
How can HTTPS be useful when doing monetary
transactions?
Chapter 16 (Part A)
Summary
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Network Models.
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The client/server and peer-to-peer networking models.
Internet Connectivity Technologies.
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ISDN, DSL, cable, and satellite. LAN connectivity to the Internet.
Network Protocols.
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Basics about TCP/IP.
TCP/IP Applications and Technologies.
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The protocols and services that run within TCP/IP.
Network Topologies.
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Four topologies you should know for the exam.
Network Types.
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Wired and wireless network technologies.
Next Lesson: Chapter 16b