CIS 337 Exam 2 Chapter 7

Explain the terms 1000Base-T, 100Base-F, 10GbE, and 10/100/1000 Ethernet.

1) 1000BaseT- 1 Billion BITs per second baseband. There is currently a revised standard evolving which makes Ethernet even faster. 100Base-F An Ethernet LAN standard that runs at 1 million bps and uses fiber-optic cable.10GbE- 10 Billion BITs per second Ethernet. Though proven to work it has yet to reach the marketplace. 10/100/1000 Ethernet - refers to the standard that can autosense which speed it needs to run at between the two speeds of 10Mbps, 100Mbps, or 1Gbps

What is a 'bottleneck' and how can you locate one?

A bottleneck is typically a point in your network that is limiting the performance of the network and you can locate one by looking at what on your network is moving much slower than the other pieces hence most likely bottlenecking.

What is a cable plan and why would you want one?

A cable plan is a plan for the network layout. This typically includes how much cable is used, where they are, and where to put the hubs. These are considered when buildings are being constructed or networks are being installed into a current system. It is what the architecture of the network depends on.

Define local area network

A local area network (LAN) is a computer network that links devices within a building or a group of them.

How does a logical topology differ from a physical topology?

A logical topology is how devices appear connected to the user as a physical topology is how they are interconnected with wires and cables.

What is a site survey, and why is it important?

A site survey determines the coverage area of network, any possible interference that could occur, and how many AP's are needed to cover this area.

How does wired Ethernet work?

A wired ethernet is considered a hub-based ethernet or traditional ethernet that uses a physical star topology. That means that all the devices receive every frame as if they were connected to the same circuit.

Explain how 'association' works in WLAN.

Association connects computers within a LAN over a wireless network in which each computer acts as a smaller device of a larger system passing signals across each other.

Many of the wired and wireless LANs share the same or similar components (e.g., error control). Why?

Because they are both generally based on the same ethernet protocol which utilizes things such as error control to ensure the correct data is being transmitted and received.

Describe the basic components of a wired LAN.

Client computer and server Network interface card Network cables Network operating system

As WLANs become more powerful, what are the implications for networks of the future? Will wired LANS still be common or will we eliminate wired offices?

Future networks will continue to increase their abilities in wireless due to the increased speed and portability that wireless offers. The main reason why wired LANs will continue to be common is partly due to the better security and reliability that a wired LAN offers. The best practice will continue to be wired networks with extra wireless capabilities in offices.

What are three 'special purpose devices' you might find in a data center and what do they do?

Load balancer- Acts as a router Storage area network- Stores the data for the LAN Network Attached Storage- Stores the data of the network

Compare and contrast the two types of antennas.

Omnidirectional antennas transmit data in all directions at the same time which are installed on most WLANS. A directional antenna transmits data in a single direction as opposed to a 360 degree area.

Compare and contrast cut-through, store and forward, and fragment-free switching.

Store-and-forward switching will wait until the entire frame has arrived before forwarding it unlike cut-through switching. Cut-through switching is considered simpler has it switches when it receives the frame and will look up the first 6 bytes of the frame that following the preamble which results in no crc error-checking throughout the process.

Describe the basic components of a wireless LAN.

The NIC- a small radio transmitter/receiver that enables a computer to transmit to receive from the access point. The access- can have a directional or omni directional antenna and is usually wired into a traditional wired network.

Describe three ways to improve network performance on the server.

The three ways are broken into two categories, software and hardware. In software, you can fine-tune the network operating system. In hardware, you can upgrade to a faster computer, increase the server's memory, and upgrade to a faster NIC.

What types of cables are commonly used in wired LANs?

Three types of cables are mostly used within a wired LAN, an unshielded twisted pair wires(UTP), shielded twisted-pair(STP) wires, coaxial cable or fiber optic cable.

Describe three ways to improve network performance on circuits.

Upgrade to a faster circuit, changing protocols, or segmenting the network.

Briefly describe how CSMA/CD works.

Using CSMA/CD, the bus waits until it is free and then transmits. Computers wait until no other devices are transmitting, and then transmit their data. CD is involved that it listens while transmitting. If NIC detects any signal other than its own, it presumes that a collision has occurred, and sends a jamming signal.

How does Wi-Fi perform media access control?

Wi-Fi listens to the network to make sure no one else is transmitting and then transmits when there is a gap.

How does Wi-Fi differ from shared Ethernet in terms of topology, media access control, and error control, Ethernet frame?

Wi-Fi uses logical and physical topologies whereas ethernet uses physical star and logical bus topologies.

How do you decide how many APs are needed and where they should be placed for best performance?

You decide how many Aps are needed by basing it off nominal data rates, error rates, efficiency of the data link layer protocols used, and efficiency of the media access control protocols.