Fundamentals of NetworkingDiscovery 1, Chapter 4Connecting to the Internet through an ISP
Objectives
•Explain what the Internet is and how we connect to it using an ISP
•Explain how information is sent across the Internet through an ISP
•Describe & identify the components of an ISP Network Operations Center
• Identify the different types of cables and connectors for connecting the devices in the NOS
•Construct & terminate twisted pair cables and determine the type of cable needed
What this Chapter is About…
•Every day people are online•We need to communicate• Internet Service Providers (ISP)▫Make this possible▫Web of service providers
•You’ll see:▫Why ISP’s are necessary▫The Network Operations Centers
What is the Internet?
•Worldwide collection of computer networks, cooperating with each other to exchange information using common standards▫Network of networks that connects users in every
country in the world•Do this through:▫Wireless, fiber, telephone lines, satellite & more
The Internet
•Who owns it?▫No one
•What allows computers to communicate?▫Protocols
•There are several organizations that help manage it▫Standards▫Addressing
Imagine…
•What would the Internet be like if no organization granted domain names?▫Might have 1000 www.nintendo.com sites
•What other areas did standards help in?▫Mobile web (other browsers)▫Any device with browser can access Internet▫Use of various devices to access web
Internet Organizations• ISOC Internet Society▫Central leadership organization
• IETF Internet Engineering Task Force▫Proposes solutions to Internet problems▫Recommends protocol standards
• IRTF Internet Research Task Force▫Researches future of Internet▫How to handle transmissions during disaster
• IANA Internet Assigned Numbers Authority▫Bookkeeper of who addresses are assigned to
ISP’s
•What’s an ISP?▫Company that provides
connections & support to access the Internet
•You MUST go through an ISP to get on the Internet
•Name yours & others
ISP Services
•What other services do ISP’s provide?▫Internet access▫Domain name registration▫Web hosting▫Transit to all over
• Internet is a series of ISP’s connected to one another
Connect to the ISP through POP
•Point of Presence•Between your LAN & the ISP•Where you get the ISP’s services- closest point of
connection
High Speed Backbone
Maps & Videos
•http://www.telegeography.com/maps/index.php
•Video 1- http://youtu.be/XQVzU_YQ3IQ
•Video 2- http://youtu.be/v1JEuzBkOD8
•Video 3- http://youtu.be/m6qTk5WNq9E
Review
1. Describe the Internet.2. What does ISP stand for?
▫ Internet Service Provider3. What does an ISP do?
▫ Provides connection to the Internet4. What is the connection point between the ISP and
your LAN?▫ POP
Options for Connecting to the ISP
•Dial-up- slowest, telephone lines• Cell Phone Modem- decently fast•DSL- high speed over phone lines• Cable Modem- high speed over cable lines• Leased Line- high speed over dedicated digital lines, for
businesses, T1• Satellite- medium speeds
Connecting to the ISP
•Modem is used to connect to ISP•You may have an ISR to connect multiple computers
to the modem
ISP Service Levels• Home Service
▫ Slower speed ▫ Less expensive▫ Less web space▫ Fewer email addresses
• Business Class▫ Faster speed▫ More expensive▫ More web space▫ More email addresses▫ SLA (Service Level Agreements)
Network availability terms Service response time Link
Data
•Data is uploaded or downloaded▫Define each
•There are two types of services for data transfer▫Usually home is different than business
Asymmetric Service•Download transfer rate is
different from upload rate▫Common in homes, most Internet
users▫Download is faster
Symmetric Service•Download transfer rate is same
as upload rate▫Common in businesses or hosting
servers▫Great for uploading lots of video,
data, graphics
Which ISP?
End of Day One
Activity
•Handout Research
•Go home & test your speed HW!
•http://www.speedtest.net
Review1. Name some features that a business class ISP
service would offer that home service does not.2. Describe asymmetric service.3. Describe symmetric service.4. What is a POP?
▫ Connection between LAN & ISP5. What’s the high speed links that connect ISPs
called?▫ Backbone
The Importance of IP
• Internet Protocol▫IP carries what you do on the Internet
With others, like TCP/IP▫Uses packets to carry data▫MUST have source & destination IP address in packet▫Routers read them
IP Packet
•Header contains the IP addresses & control info for routers▫Sometimes called a datagram
• IP addresses MUST be unique• ISP gets blocks of addresses from Internet Registry▫Then they manage & split them up
How an ISP handles Packets•Message is divided into smaller packets▫64-1500 bytes▫Downloading a 1 MB song requires over 600 packets of 1500
bytes each• ISP determines whether packet is for local ISP service or
for remote network
NOC• Controls traffic flow▫ Uses destination IP▫ Passes from router to router
• Has services (web hosting, email)
NOC- AT &T Monitoring
Network Utilities- Ping•Ping▫End-to-end
connectivity▫Round trip time▫ICMP echo request
Network Utilities- Traceroute
•Traces path from source to destination
•Displays each hop•Shows where problem
is
• In windows, tracert
Activities
•Packet Tracer 4.2.3.2- Observe Packet Travel
• Lab 4.2.3.3- Use ping, traceroute, visual traceroute and whois to check connectivity and IP addresses and learn more about how packets travel through the Internet.
The Internet Cloud- 4.3.1•Many routes to a destination▫Bad router- take the back road!
•Cloud represents Internet or another network
Devices in the Cloud•More than just routers in cloud•Technology at home must match tech at ISP▫DSL connects to a DSLAM (access multiplexer)▫Cable Modem connects to a CMTS (termination
system)▫Analog dial-up modem access▫Wireless access
Devices in the Cloud
Devices in the Cloud- At ISP•Must have equipment to connect to other ISPs•Must handle lots of traffic, near 100% uptime,
redundant
Activity- NOC Equipment
Review1. A DSLAM is needed at the ISP for which technology?
▫ DSL2. What does DSL stand for?
▫ Digital Subscriber Line3. A CMTS is needed for which technology?
▫ Cable Modem4. What do you need to connect to the Internet?
▫ IP Address, default Gateway, connection to a network, and an ISP to connect you
ISP Equipment Requirements
•Servers to provide services▫Need steady, reliable power▫UPS
ISP Equipment Requirements
•Air & humidity levels•Cable management▫Protect from damage & kept organized
Common Network Cables
•What’s another name for cable?▫Medium▫Channel
•Copper•Fiber Optic•Wireless
Network Cables We’ll Discuss
Twisted Pair Cabling•Electricity over the copper wires•Pairs twisted inside jacket•Can get EMI•Crosstalk on long runs▫Signal jump cables▫Cat 5 has 3-4 twists per inch▫Makes it more resistant to interference
Kinds of Twisted Pair•UTP▫Electricity▫Inexpensive▫Easy to install▫4 pairs of wires, color
coded▫RJ45 connector
•Cat 5 & 5e▫100 & 1000Mbps
•Cat 6▫1000Mbps & higher
Review
1. What connector is on UTP?▫ RJ45
2. What is the high speed links called that connect ISPs?▫ Backbone
3. A router, switch & access point all in one is called what?▫ ISR
Coax Cable
•Transmits electricity•Better shielding than UTP•Harder to install than UTP• ISP uses these for CMTS
Fiber Optic Cables•Transmits pulses of light•Used in big environments•Glass or plastic▫No EMI
•High speed▫LAN backbone▫Connect ISP to Internet
•2 fibers▫Transmit & receive
Fiber Optic Cables•Multimode▫ Less $, used more▫Used in LANs/Campuses
2000 meters▫ LED▫Many paths of light
•Single Mode▫More $, faster speed▫Connects backbone/NOCs
3000 meters▫ LED laser▫Single path of light
Activity- Fiber or UTP?
Cabling Standards
•Specs for installing & testing cable▫Pinouts (order of wires)▫Wire sizes▫Shielding▫Cable lengths▫Connector types ▫Performance limits
Straight-Through Cable• 568B to 568B• Connect unlike devices▫ Computer to Hub/Switch▫ Switch to router port
•On the PC NIC▫ Pins 1 & 2 transmit▫ Pins 3 & 6 receive
Crossover Cable• 568A to 568B• Like Devices▫ Switch/hub port to switch/hub port▫ Router port to router port▫ PC to router port▫ PC to PC
UTP Termination
•RJ45 male connector• Jack is female
Let’s make cables!•Straight-through•568B to 568B
•White-Orange•Orange•White-Green•Blue•White-Blue•Green•White-Brown•Brown
Let’s make cables!• Crossover• 568B to 568A• Change Oranges & Greens on ONE
SIDE!
•White-Green• Green•White-Orange• Blue•White-Blue•Orange•White-Brown• Brown
Terminating•Patch Panel▫Switchboard▫Quickly
rearrange▫RJ45
• Jacks
Testing Cables
•Open▫Wire not in connector▫Break in wire
•Short▫Copper touches another
•Reversed Pair•Split Pair
Other Tests- Degradation
•Attenuation▫Measure of signal strength▫If message fades at destination, will not be understood
•Crosstalk▫Signal leaks onto another pair of wires▫Can happen if cables are not terminated properly or
low quality connectors
Cabling Best Practices- Yes or No•Cable Management▫Keeps wires neat & organized to easily find problems▫Protected from damage
Review
•Which cable would you use:▫In your house?
UTP▫Between buildings?
Fiber▫To your cable modem?
Coax▫Where you get a lot of EMI?
Coax or fiber, NOT UTP!!
Review- 10
Fundamentals of NetworkingDiscovery 1, Chapter 3Connecting to the Internet through an ISP
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