Chapter 8 ITE 1 Basic Networking ITE 1 Basic Networking

Networking Basics Two Basic Types of Connections Are: WAN Wide Area Network Think Modem - Long distances LAN Local Area Network Think This Room Two Basic Types of Connections Are: WAN Wide Area Network Think Modem - Long distances LAN Local Area Network Think This Room

Connection Media Copper Cabling Coax or UTP UTP is limited to 100 meters Fiber Uses glass strands to carry pulses of light No electrical issues - Longer Distances Wireless Radio signals or infrared Copper Cabling Coax or UTP UTP is limited to 100 meters Fiber Uses glass strands to carry pulses of light No electrical issues - Longer Distances Wireless Radio signals or infrared

Connection Media UTP Cabling Unshielded Twisted Pair Uses Copper Wire Number of twists and number of conductors determine category number (Cat 3, Cat 5, Cat 6 etc.) UTP Cabling Unshielded Twisted Pair Uses Copper Wire Number of twists and number of conductors determine category number (Cat 3, Cat 5, Cat 6 etc.)

Oddball WAN Media Power lines (PLC) can be used to carry both voice and data. It can actually provide higher bandwidth than phone lines (PSTN) Power lines (PLC) can be used to carry both voice and data. It can actually provide higher bandwidth than phone lines (PSTN)

Why Network? Share files and resources Lower Cost Software Licensing Central Administration Share files and resources Lower Cost Software Licensing Central Administration

WLAN Are wireless LAN’s Can cover small or large areas. Small area connections use shared bandwidth. Are wireless LAN’s Can cover small or large areas. Small area connections use shared bandwidth.

Network Types There are two basic types of networks Peer to Peer All machines are equal No central administration Client/Server Networks Centrally administered Lots of control and security, but increased overhead Easy data backup and centralized access to data There are two basic types of networks Peer to Peer All machines are equal No central administration Client/Server Networks Centrally administered Lots of control and security, but increased overhead Easy data backup and centralized access to data

Bandwidth Network speed is measured in Bandwidth Bps - Bits per second Kbps - Kilobits per second Mbps - Megabits per second Network speed is measured in Bandwidth Bps - Bits per second Kbps - Kilobits per second Mbps - Megabits per second

Communication Direction Simplex One way transmission Think Radio Station Half-Duplex One Direction at a time Think Walkie Talkie Full-Duplex Both directions at once Think telephone Simplex One way transmission Think Radio Station Half-Duplex One Direction at a time Think Walkie Talkie Full-Duplex Both directions at once Think telephone

Network Addressing Broken into three classes Class A: 1st Octet is a Network Address Class B: 1st and 2nd Octets are Network Addresses Class C: 1st, 2nd and 3rd Octets are used to identify the network address Broken into three classes Class A: 1st Octet is a Network Address Class B: 1st and 2nd Octets are Network Addresses Class C: 1st, 2nd and 3rd Octets are used to identify the network address

Network Addressing The remaining addresses are used for individual devices on each type of network.

Network Addressing Addressing can be done by the administrator and manually added to each machine or Done automatically through a process called DHCP where the address are handed out on a temporary basis Addressing can be done by the administrator and manually added to each machine or Done automatically through a process called DHCP where the address are handed out on a temporary basis

Network Addressing Network Addressing has 3 Parts IP Address - Must be unique for every machine on the network Subnet Mask - Should be the same for every machine on the network Tells the network which part of the IP is for the network address and which part is for the individual devices Gateway - Tells the machine where to send the packets that go to the internet Machines can communicate locally without the proper gateway address. Network Addressing has 3 Parts IP Address - Must be unique for every machine on the network Subnet Mask - Should be the same for every machine on the network Tells the network which part of the IP is for the network address and which part is for the individual devices Gateway - Tells the machine where to send the packets that go to the internet Machines can communicate locally without the proper gateway address.

Protocols Protocols are a set of rules that govern communications See page for a list of common protocols Protocols are a set of rules that govern communications See page for a list of common protocols

ICMP Internet Control Message Protocol is used to send messages between devices regarding network conditions One type of ICMP is called Packet Internet Groper or PING It is used to test end to end connectivity between devices Tracert shows the whole route the packets took along with timing. Internet Control Message Protocol is used to send messages between devices regarding network conditions One type of ICMP is called Packet Internet Groper or PING It is used to test end to end connectivity between devices Tracert shows the whole route the packets took along with timing.

How Information is Sent Files are broken down into segments. The segments get headers and trailers added for addressing and error checking. This process is called Encapsulation. Files are broken down into segments. The segments get headers and trailers added for addressing and error checking. This process is called Encapsulation.

Network Devices Hubs Hubs are “Dumb Devices” They are really multi-port repeaters. They simply send anything they receive in any one port out all of their other ports. They run at Half-Duplex only. They extend the network without breaking it into segments as switches and routers do. Hubs Hubs are “Dumb Devices” They are really multi-port repeaters. They simply send anything they receive in any one port out all of their other ports. They run at Half-Duplex only. They extend the network without breaking it into segments as switches and routers do.

Network Devices Routers Routers make forwarding decisions based upon programming. They are very smart devices and can dynamically reroute packets as network conditions change. Routers Routers make forwarding decisions based upon programming. They are very smart devices and can dynamically reroute packets as network conditions change.

Network Devices Switches Switches and Bridges (Bridges are single-port switches) are smarter than hubs. They make forwarding decisions based upon Mac (Hardware) Addresses They are good because they block unwanted traffic. Switches Switches and Bridges (Bridges are single-port switches) are smarter than hubs. They make forwarding decisions based upon Mac (Hardware) Addresses They are good because they block unwanted traffic.

Network Topographies Ethernet Standard (IEEE 802.3) systems use a Star physical topology But their logical topology is actually a bus topology There are other types including a Mesh Topology where everything is connected to everything else and a Ring Topology which is just as it sounds. Ethernet Standard (IEEE 802.3) systems use a Star physical topology But their logical topology is actually a bus topology There are other types including a Mesh Topology where everything is connected to everything else and a Ring Topology which is just as it sounds.

Ethernet Standards Wireless Standard can be found on page One of the most common is g which runs at speeds up to 54 mps. Wireless Standard can be found on page One of the most common is g which runs at speeds up to 54 mps.

How LAN’s Work To avoid collisions where multiple devices try to talk at once: Ethernet uses CSMA/CD When a collision occurs all devices back of a random amount of time, then listen to see if the coast is clear before resending To avoid collisions where multiple devices try to talk at once: Ethernet uses CSMA/CD When a collision occurs all devices back of a random amount of time, then listen to see if the coast is clear before resending

Models There are two models for explaining how Networking is done. One is TCP/IP The other is the OSI Model See pages for an explanation of the different models and how they relate to each other. There are two models for explaining how Networking is done. One is TCP/IP The other is the OSI Model See pages for an explanation of the different models and how they relate to each other.

OSI Model Explains how things work. Makes it so equipment and software from different sources will work together. Explains how things work. Makes it so equipment and software from different sources will work together.

OSI Model Data link layer controls physical addressing otherwise known as the MAC address.

VoIP What is VoIP? It’s voice (As in Telephone) over a computer network. (Voice Over IP) Advantage: It’s very cheap. Think Vonage Disadvantage: If your internet goes down so does your phone service. What is VoIP? It’s voice (As in Telephone) over a computer network. (Voice Over IP) Advantage: It’s very cheap. Think Vonage Disadvantage: If your internet goes down so does your phone service.

Other Odd Ways of Connecting PLC Carries Voice and Data Across Power Lines Requires no control wiring for electrical devices at the customer’s end. Actually has more bandwidth than most other WAN technologies PLC Carries Voice and Data Across Power Lines Requires no control wiring for electrical devices at the customer’s end. Actually has more bandwidth than most other WAN technologies

Other Ways To Connect ADSL Uses existing phone lines Faster download (Downstream) speeds than up upload (Upstream) speeds. Limited distance from the phone company switching center. ADSL Uses existing phone lines Faster download (Downstream) speeds than up upload (Upstream) speeds. Limited distance from the phone company switching center.

Other Ways to Connect ISDN Uses 2 phone lines - 3 Channels, 2B and one D. Faster than dialup, but slower than cable or DSL. Expensive Called BRI Not used much anymore. ISDN Uses 2 phone lines - 3 Channels, 2B and one D. Faster than dialup, but slower than cable or DSL. Expensive Called BRI Not used much anymore.

That’s It! Good luck on the test!