Subject: Networking Essentials (70-58)

Well I passed Networking Essentials this morning with an 879. Not an easy test but with the right preparation, you'll do just fine. Some of the main points to know are:

User-Level Security: Nt Workstation and NT Server

Share-Level: WFW and 95 (Unless 95 is in a Domain- then it is User-level as well)

7 Layers of the OSI

Physical - Data Link - Network - Transport - Session - Presentation - Application (or "Please Do Not Throw Sausage Pizza Away ;-)

Which level is responsible for security: Session

Which level is responsible for compression: Presentation

Which level is responsible for the data format: Presentation

Which level is responsible for putting check points in the data stream: Session

Which Device is at the Physical Layer: Repeater

Which Device is at the Data Link Layer: Bridge

Which Device is at the Network Layer: Router

Which Device is at or above the Transport Layer: Gateway

Know the IRQ's:

• IRQ 3: Com 2&4
• IRQ 4: Com 1&3
• IRQ 5: LTP2 or a Second Nic
• IRQ 7: LPT1

Know the topologys: Ring, Star, Bus

• Bus -is the easiest and a good temporary topology -difficult to troubleshoot -1 computer going down does affect the entire network
• Star -is connected to hub -easier to troubleshoot -1 computer going down't affect the entire network
• Ring -is in a circular position -not to difficult to troubleshoot (a computer "beaconing" gives off the location b/c it cannot talk to it's neighbor) -1 computer going down does affect the entire network

Know the Cabling types: (Most buildings come with CAT 1 or 3 UTP)

10BaseT :UTP or STP category (CAT): 1 -4 MB/s

3 -10MB/s

5 -100MB/s

Distance: 100 Meters (328ft)

10Base2 :Thinnet, RG-58 U, A/U, Uses BNC T and BNC Barrel connectors.

Cable diameter is 1/4"

Distance: 185 Meters (607ft)

10Base5 :Thicknet, called "Standard Ethernet", Uses a 15pin DIX or AUI connecter to plug into the network card. Cable diameter is 1/2" (inch)

Distance: 500 Meters

100BaseX :"Fast Ethernet" (Both 100BaseX and 10BaseT are in a star type topology).

100BaseFL :Fiber-Optic, 10MB/s

Fiber Optic: Good for a Back bone, also used in FDDI networks (Redundancy) Distance: 2Km

Frame Relay: "Bandwidth on Demand", uses Permanent Virtual Circuts (PVC), variable-lengh packets

ATM: Supports Voice, Video, and Data. Theoritical possibility of 622MB/s, normally 122 MB/s now.

Multiplexer: Puts the Video and Data onto the same line

SLIP and PPP are dialup methods. ONLY PPP supports compression and Error correction.

In Troubleshooting, if you see a reading of O (Zero) using an osilicope or TDR: Replace the Cable.

You use a TDR during the installation of new cable.

A Protocol analyzer can look inside packets.

A Gateway is a protocol translater and can translate 1 format to another, also it can translate an email information (i.e. CCMail to Exchage).

If you are unable to connect to the network with 1 computer, it is: 1 of the following choices: incorrect FRAME type (IPX), Wrong IRQ, or wrong Transceiver type.

In a small network w/ 8-10 Windows 95' Computers use: Netbeui (or IPX -NOT NWLINK <--NT)

Routable Protocols: IP, IPX, XNS, OSI, Appletalk, DECnet

Non-Routable: Netbeui, LAT, DLC

IPX is a NETWORK protocol.

Netbeui is a Transport protocol.

Differences between a bridge and router:

1) A bridge CAN forward broadcast traffic

2) A bridge forward packets based on the MAC address

3) You use a bridge to "Segment" a network. (Exam tip- if you see the word "Segment"- use a bridge)

4) A bridge can link unlike media (10BastT to 10Bast5, or from STP to Token Ring, ect)

5) A router stops Broadcast Storms

6) A router looks at the Network address when forwarding network addresses

7) A router can be used to break up a netowork with different protocols (a router will not forward Netbeui broadcasts)

8) A router can also link media but it has to be of the same media type.

A variation called a Brouter can do the jobs of both, choose it when you can. (Forward Netbeui broadcasts). On of the exam questions was answered by, "Turn off Bridging on all Brouters" -this seperated the networks and stops broadcast storms.

• Raid Level 0: Disk Striping (No Fault Tolerance)
• Raid Level 1: Disk Mirroring, Duplexing (Fault Tolerant)
• Raid Level 5: Disk Striping with Parity (Fault Tolerant), Data and Parity on seperate disks.

Crosstalk- signal overflow from an adjacent wire

Attenuation- Loss of signal strengh over the distance of the cable.

Well that sums up the bulk of the test questions. Remember that Bill G's goal in life is to trick you so READ EACH QUESTION THROUGHLY!!!! As for me Im going to step outside my door now and try to figure out what that bright thing up in the sky is. Happy Hunting!!!