CNIT 344 Final Exam

Goes over multiple topics from Purdue CNIT 344

OSI Layer 1

Physical Layer, Data Type: Bits

OSI Layer 2

Data Link Layer, Data Type: Frames

OSI Layer 3

Network Layer, Data Type: Packets

OSI Layer 4

Transport Layer, Data Type: Segment

Ethernet, USB, Bluetooth, Hub, Repeater are associated with what layer?

OSI Layer 1

PPP, ALIP, ATM, Switch, Bridge, Wireless AP (WAP) are associated with what layer?

OSI Layer 2

IP, ARP, ICMP, Routers are associated with what layer?

OSI Layer 3

TCP and UDP are associated with what Layer?

OSI Layer 4

OSI Layer 5

Session Layer, Establish Interhost communication

OSI Layer 6

Presentation Layer, Formats data for viewing

OSI Layer 7

Application Layer, End user application

HTTP, DNS are associated with what layer?

OSI Layer 7

JPEG, GIF, ASCII, SSL, IMAP are associated with what layer?

OSI Layer 6

NFS, RFC, SQL, and NetBIOS are associated with what layer?

OSI Layer 5

OSI Stands for

Open System Interconnection

Analog Bandwidth calculation

Fmax - Fmin

Serial Transmission

one bit at a time

Parallel Transmission

multiple bits at a time

Synchronous Transmission

Time based (clock based) no gap between data items

Asynchronous Transmission

Signal based (start & stop bits)

Common implementations of Serial Transmission

Telco/ISP links

Ethernet

SATA

Common implementation of Parallel Transmission

PCI, Memory bus, Many HDD Interfaces, Older Printers & some scanners.

Timing and transmission for Serial & Synchronous

T-Carrier system, SONET

Frame Relay, xDSL, ISDN

USB, Firewall

Timing and transmission for Serial & Asynchronous

Most “Terminal“ applications, keyboard, mice

ATM

Firewall

Timing and transmission for Parallel & Synchronous

Internal buses

Printers & Scanners

Timing and transmission for Parallel & Asynchronous

Not many communications protocols or standards

Reviewed for HPC

Simplex Communication

Full-Duplex Communication

Half-Duplex

What does Duplex Auto-negotiation do?

Set link speed and duplex mode

What is Modulation?

The process of converting digital bits into an analog signal so it can be sent over an analog medium

What is Demodulation?

The process of converting an analog signal into a digital bit stream is called Demodulation

Devices that preform Modulation and Demodulation

modems

Amplitude Modulations: Carrier

Carrier

Amplitude Modulations: Signal

Signal

Amplitude Modulations: Modulated Carrier

Modulated Carrier

What is Frequency Modulation?

Manipulate the frequency of the carrier wave in order to indicate data

What is Phase Modulation

Manipulation of the phase of the carrier wave in order indicate data

What is Shift Keying

The term that is used when the signal is digital rather than modulation.

What is Frequency Division Multiplexing?

Each source data stream is assigned to a specific sub-frequency of the channel

A guard band is required to minimize adjacent channel interference.

What is Time Division Multiplexing

Data can only be sent during assigned timeslots.

Each source data stream is assigned to a timeslot in the channel

What is Code Division Multiplexing

Each source data stream is assigned a unique orthogonal code for use in the entire channel

Any overlapping data streams are seen as noise in the system and is ignored.

How do the OSI Layers communicate with each other?

Adjacent layers only

What does open interconnection mean for the OSI model?

Multi-vendor environments can be supported due to connection between layers

What do layers rely on for layers above/below them?

To perform their layers specific functions

Responsibility of OSI Layer 1: Physical

Transmission and receipt of the bit stream to and from nodes; concerned with signaling techniques

Responsibility of OSI Layer 2: Data Link

Providing point to point validity of the data and reliable operation of communication links

What are the two sub-layers of the data link layer?

MAC

LLC

Responsibility of OSI Layer 3: Network

Enables Internetworking

provides globally-unique addressing and routes

Responsibility of OSI Layer 4: Transport

Host to Host integrity of transmissions and detecting damaged or lost packets and generating retransmit requests.

Responsibility of OSI Layer 5: Session

Establishing, Maintaining and terminating host to host interactive sessions.

What are ports used for in Layer 5?

To uniquely identify a service/application/function on a host

Responsibility of OSI Layer 6: Presentation

Managing the way data is presented, encoded, translated (ASCII/Unicode), encrypted and compression.

Responsibility of OSI Layer 7: Application

Interface between user applications and network services

What is encapsulation?

Wrapping data with headers/trailers as it moves down in the OSI Model/Layers

What is decapsulation

Removing headers/Trailers as data moves up the OSI Model/Layers

What is Multiplexing?

Combining multiple data streams into one channel

What is IEEE?

Institute of Electrical and Electronic Engineers, A professional organization that defines the standards for many LAN protocols

What is the standard TIA (Telecommunications Industry Association) and EIA (Electronic Industries Association)

A standards organization covering structured voice and data wiring for LANs

Common means for connecting network devices

Copper Media (Fluorescent Lighting, Radio waves, and Electric motors)

Wiring pattern for T568A (Ethernet)

Striped Green

Green

Striped Orange

Blue

Striped Blue

Orange

Striped Brown

Brown

Wiring Pattern for T568B (Ethernet)

Striped Orange

Orange

Striped Green

Blue

Striped Blue

Green

Striped Brown

Brown

Wiring for a straight through cable

Same pattern throughout the cable (T568B or T568A)

Wiring for a crossover cable

Used both cable types one for each end of the cable (T568B or T568A)

Purpose of a Straight-Through cable

Connecting a device to a switch/hub

Purpose of a Crossover cable

Connecting two of the same devices to the same device (Switch to Switch/Router to Router)

What is a coaxial cable?

Used in wireless and cable access technologies

What is the use case for a rollover cable?

Connecting a workstation serial port to a Cisco networking device console port using a nine-pin adaptor

What are shielded twisted pairs

Shields the entire bundle of wires within the cable as well as the individual wire pairs to provide better noise protection that UTP

What are Hybrid Fiber-Coax

Cable structure used to provide two-way communication over a coaxial cable (i.e. cable connection to the internet

Standard IEEE 802.11

Wireless LAN (WLAN); Uses a contention system with Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA)

Standard IEEE 802.15

Wireless Personal Area Network (WPAN); Uses a device pairing process to communicate over distances from 1-100 meters

Standard IEEE 802.16

Wireless broadband access; uses a point to multipoint topology to provide wireless broadband access

Minimum frame lengths

512 bits / 64 bytes

Maximum frame length

12144 bits / 1518 bytes

What happens if the first bit is 0 in an address

It is a unicast, if not it is a multicast

Standard Ethernet is how fast?

10 Mbps

Fast Ethernet is how fast?

100 Mbps

Gigabit Ethernet is how fast

1 Gbps

Ten-Gigabit Ethernet is how fast?

10 Gbps

What is a Ad Hoc

Wireless networks can operate without access points

client stations which are configured to operate in ad hoc mode configure the wireless parameters between themselves