1. Fall 2013 Networking Presentation

2.     Networks
Networks are a collection of computers and other hardware connected together.
They provide communication between a minimum of two devices.
Networks come in various topologies.
Each topology has advantages and disadvantages when compared to each other.

3. Ring Topology All devices are connected to each in a virtual ring.
Uses a token to communicate between the devices.
Only the computer with the token can transmit to the other devices.
The system uses a Multi-Station Access Unit (MAU) hub.
The MAU sends the signal to each device in the ring, until the computer with the token receives the original message back.

4. Ring Network

5. Star Topology Most popular topology.
            
Offers greater flexibility over other topologies.
Each device has a dedicated connection to the hub or switch. 
The entire network can be affected if the central hub or switch fails. 

6.     Star Network

7. Bus Topology Also known as Daisy Chain.
           
Signals from each device travel on a bi-directional bus.
The Bus has two cable ends that must be terminated.
A faulty cable, terminated end or bad connection will affect the entire network.
A split in the network will cause signals to become scrambled across the whole network.  

8.    Bus Topology
CSMA / CD. 
           
Carrier Sensing - Multiple Access / Collision Detection.
Is software that senses when the line is busy.  

9.    Bus Network

10. It is only practical for small sized networks.
   Mesh Topology
Each computer has a dedicated connection to every other computer on the network. 
           
It is only practical for small sized networks.
It is more tolerant to device and cable failures than other topologies.  

11.    Mesh Network

12.    Hybrid Networks
Are designed to take advantage of the strengths of each combined network. 
           
Help minimize the weaknesses of the combined networks.
It can handle device and cable failures better than the individual networks on their own.
Star/Bus and Star/Ring are two examples of Hybrid Networks. 

13.    TCP / IP
A group of networking protocols used to connect computers on the Internet.
TCP provides transport functions while IP provides the addressing and routing mechanism.
TCP/IP includes FTP, SMTP (Simple Mail Transfer Protocol),Telnet and UDP (User Datagram Protocol)  

14. DHCP Dynamic Host Configuration Protocol (DHCP).
DHCP is used to dynamically assign IP addresses on the network.
DHCP is used to conserve IP addresses.
When a device connects to the network, DHCP will "lease" an IP address to it.
When that device is not using the network, DHCP can use the same IP address for another device.  

15. Network Communications
Half Duplex is where a device is only capable of one way communications. Send or Receive.
Full Duplex is where the device can both send and receive signals at the same time.

16.   Network Wiring

17.     Network Cables

18.   Twisted Pair Cable
Twisted Pair Cables are currently the most commonly used network cables.
Frequently used in Star Topology Networks.
Available in shielded and non-shielded styles.
It has eight individual wires twisted into four pairs, enclosed inside a single sheath. 
The pairs are twisted at different rates to reduce interference.  

19.   RJ45

20.   Twisted Pair Cable
The Telecommunications Industry Association (TIA) and Electronics Industry Association (EIA) developed the  TIA/EIA-568 standard.
CAT-5 10BaseT or 100BaseT can be wired two different ways and maintain conformance with T568A or T568B standards.
10Base and 100Base ethernet networks generally use only two of the four twisted wire pairs.  

21.   Twisted Pair Cable
Category 5 (CAT-5) cable is the most common standard used today.
CAT-5 is suitable for networks running at 100 Mbps or slower.
CAT 5e cable is designed at a 100 MHz frequency on cable segments of up to 100 meters. 
Depending on performance standards, CAT-5 can be used in 1000BaseT networks.  

22.   Twisted Pair Cable
CAT-6 is suitable for networks running at 1000 Mbps up to 100 meter segments.
CAT-6 cable can support 10 Gbps on cable segments of up to 55 meters.
CAT-6a will support 10 Gbps networks up to 100 meter segments.  

23.    Twisted Pair Cable

24. Shielded Twisted Pair Cable
Shielded Twisted Pair Cables come in two types.
Type 1A and Type 6A.
It is used where additional shielding is needed against electromagnetic interference.
It only has two pairs of twisted wires with the addition of foil or mesh shielding.
Frequently used in Ring Topology Networks.  

25.    RJ45 & RJ11

26. RJ45 vs RJ11 RJ stands for Registered Jack.
RJ45 is used with ethernet cables in computer networking.
 RJ11 is used in connecting telephone units.
RJ45 contains more wires,(8) than RJ11 (4).
RJ45 is physically bigger than RJ11 to accommodate the extra wires.  

27.    Coaxial Cable

28.   Coaxial Cable
Two types of Coaxial cable are used for computer networking.
RG-8 (Thick ethernet) Is a 10Base5 format that has a maximum cable length of 500 meters.
RG-58 (Thin ethernet) Is a 10Base2 format that has a maximum cable length of 200 meters.
Both are limited to a speed of 10 Mbps & use base-band transmissions.
Frequently used in Bus Topology Networks.  

29.    Coaxial Cable

30.   Fiber Optic

31.   Fiber-optic Cable
Fiber-optic cable carries light instead of electrical signals.
Normally has the light converted to electronic impulses when connecting to the NIC .
It is resistant to any electromagnetic interference.
It can span distances of 120km without signal degradation. 
It offers a more secure form of transmission.  

32. Fiber Optic Connections

33.   Fiber-optic Cable
There are two types of fiber-optic cable, single-mode and multimode.
Single-mode uses a laser as a light source and has a smaller core.
Multimode uses a LED as a light source and can process multiple wavelength signals.
Two common connectors used in fiber-optics include the Straight tip (ST) and the Subscriber connector (SC).  

34.    Plenum Rated Cable

35.   Plenum Rated Cable
The plenum is an open space found above a building’s dropped ceilings.
Plenum spaces often house telephone and network communication cables.
Plenum rated cables must comply with the NEC specifications for flammability and smoke density.
Plenum rated cables need to be coated in flame-retardant, low smoke materials such as polyvinyl chloride (PVC). 

36.   Network Hardware

37. Repeaters are simple devices that act as a signal amplifiers.
Repeaters can remove noise from the incoming signal, but cannot correct corrupted messages.
Repeaters can be used as media adapters, such as converting signals from a fiber-optic line over to a twisted pair line.
The use of repeaters should be avoided on network segments with high volumes of traffic.   

38.   Routers

39.   Routers
Routers are used to transfer information between separate networks.
Routers can analyze and in some cases correct corrupt packets of data.
They use a routing table to direct information to the correct network address.
Routers must be directly connected to each network and have an IP address in each network.   

40.   Network Hub

41.   Network Hubs
Hubs are simple devices used to connect multiple computers together.
They are available in active and passive configurations.
Hubs lack the ability to route incoming messages and broadcast on all output lines.
Hubs are used in Token Ring networks as a Multi-station Access Unit (MAU). 
Hubs must operate in half-duplex mode.  

42.   Network Switch

43.   Network Switches
Network switches act as a central connection point for network devices.
Frequently used in Star Topology Networks.
Switches directly send received messages to the destination address.
This allows the switch to operate in full-duplex mode.  
Switches help reduce network collisions and as a result increase network bandwidth.  

44.   Network Switch

45.   Network Switches
Switches improve network security by limiting communication to specific ports.
Switches can read and analyze the data they are receiving.
This makes them useful for troubleshooting network problems.
Switches can be configured to either manually or auto negotiate half or full duplex modes with other network devices.