1. Troubleshooting a “Broken LAN”
Telecommunications and Networking
Troubleshooting a “Broken LAN”

2. Networking Basic Diagram
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3. 32 Bit Dotted Decimal Number:
IP Address
32 Bit Dotted Decimal Number:
Decimal
Number
Range
Octet
Octet
Octet
Octet
Binary
Equivalent
(Either 0 or 1)
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4. Network ID
RED- Bits associated with the Network ID, must remain intact for routing through the Internet Black- Bits associated with individual hosts on the network. These bits can be used to assign host addresses on the network Class A Address Class B Address Class C Address
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5. Basic Networking Terms
Straight-Through Cable- An Ethernet cable used in networks which connect unlike devices (ex.- PC to Switch, PC to Hub)
Cross Connect Cable- An Ethernet cable used in networks which connect like devices (ex. – PC to PC, Hub to Hub)
Console Cable- An Ethernet cable used in networks which connect a PC to a console port of a router or switch and allows configuration to take place.
Router- A network device which routs IP packets through the Internet based on the network IP address.
Switch- A network device which routs network frames to their specific MAC destination address.
NIC (Network Internet Card)- An adapter card which, when inserted into a computer or laptop, allows an Internet connection to that device.
Packet- A packet is a unit of information which is routed through the Internet by routers.
Frame- A frame is a container of data within a packet which is reviewed and sorted to individual hosts on a network by a switch.
Peer to Peer Network- The simplest form of a network where a host is acting as both client and server on the network.
Client-Server Network- A network where there is a central control of all network services (server) to network hosts (clients).
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6. Lab Diagram Set up the following equipment for each of the groups:
Router
Straight- Thru Cable
Switch
Straight- Thru Cable
Hub
(3) Straight- Thru Cables
(3) CPU’s- with Operating
Systems, Working NIC’s
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7. Instructions Configure all equipment with IP addresses including:
Router:
Gateway
Network ID/ Subnet Mask
CPU’s:
IP Address/Subnet Mask
Default Gateway
TCP/IP Protocol Suite
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8. Instructions- Cont. All other CPU’s
Connect all cables
Check system by use of “ping” to:
All other CPU’s
Default Gateway
After ensuring correct functions, create errors in the network by doing any or all of the following:
Change IP addresses of a CPU or Default Gateway to be non compatible with rest of network
Use incorrect or damaged cable for any of the connections
Change Subnet Mask or Network ID in router
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9. Instructions- Cont.
Allow students to investigate the LAN in order to find out possible errors in the network
Students should then repair the problem
Students should then document the entire process on a Lab Report Form
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