M-Exam Flashcards
Transmitted data both analog and digital are susceptible to many types of ____ and ______?
Noise and Errors
Unwanted electrical or electromagnetic energy that degrades the quality of signals and data.
Noise
Occurs in digital and analog systems, and can affects files and communications of all types including text, programs, images, audio, and telemetry.
Noise
a condition in which data on digital medium has been altered erroneously.
Error
are unavoidable, caused by noise on channel.
Error
complete link layer messages are called ______?
Frames
is a digital data transmission unit in computer networking and telecommunication.
Frames
it contains the source and the destination addresses of the frame.
Frame Header
it contains the messages to be delivered.
Payload Field
it contains the error detection and error correction bits.
Trailer
it marks the beginning and end of the frame.
Flag
these errors are occured in the communication media due to signal distortion or attenuation.
Transmission Errors
these errors occurs due to data storage where the memory tracks will corrupt during writing of by any power supply failures.
Storage Errors
Kinds of Transmission Error
- sent signal destroyed - doesn’t receive data
- sent signal changed - received wrong data
- spurious signal created - received random data
if two or more bits are different between sending and receiving data stream, then the error is called _____?
Multiple Bit Error
two or more bits changed in the transmitted data and the error is calculated from starting error bit to the ending error bit.
Burst Error
techniques that allow the destination to detect errors
Error Detection
to detect and correct errors, enough redundancy bits need to be sent with data.
Error Detection
are the extra bits sent by source to inform destination about the data sent.
Redundancy Bits
Types of Redundancy Check
- Parity Check
- Longitudinal Redundancy Check
- Cyclic Redundancy Check
one extra bit is sent along with the original bits to make number of 1s either even in case of even parity.
Parity Check
is an error detection method for determining the correctness of transmitted and stored data.
Longitudinal Redundancy Check
also known as Horizontal Redundancy Check.
Longitudinal Redundancy Check
is an error detecting code commonly used in digital networks and storage devices to detect accidental changes to raw data.
Cyclic Redundancy Check
is an error detection method in the transmitter computes a numerical value according to the number of set or unset bits in a message frame.
Checksum
also known as Hashsum.
Checksum
Types of Commonly Used Checksum
- Cksum
- Md5sum
- Jdigest
- Jacksum
- Jcksum
is the next step of error detection.
Error Correction
is the best error correction technique used in the receiver to detect an error.
Hamming Distance Code
is the smallest number of bit differences that turn any one codeword into another.
Hamming Distance Code
is the best error correction technique.
Hamming Distance Code
2 ways of error correction
- Forward Error Correction
- Backward Error Correction
it executes error-correcting code.
Forward Error Correction
it requests back the sender to retransmit the data unit.
Backward Error Correction
is the process of detecting and correcting both the bit level and packet level errors.
Error Control
receiver detects and corrects lost or corrupted data.
Error Control
refers to the way in which endpoints or stations attached to the network are interconnected.
Topology
refers to the shape of network or the network’s layout
Topology
may define both physical and logical aspect of the network
Topology
is either a redistribution point or a communication endpoint.
Node
is the arrangement with which computer systems or network devices are connected to each other.
Network Topology
Kinds of Network Topologies
- Point to Point
- Bus
- Star
- Mesh
- Ring
- Tree
- Hybrid
is a connector that either splices into the main cable or punctures the sheathing of a cable to create a contact with the metallic core.
Tap
is connection running between the device and the main cable.
Drop line
two ring networks are formed called?
Dual Ring Topology
2 Types of Mesh Topology
- Partially Mesh
- Full Mesh
all hosts have a point to point connection to every other host in the network.
Full Mesh
not all host have point to point connection to every other host.
Partially Mesh
Hierarchical Topology also known as?
Tree Topology
Types of Transmission Errors
- Single Bit Error
- Multiple Bit Error
- Burst Error
is the host computer, and at the end of each connection is terminal.
Central Hub
Layer 1 (Central Hub)
Hub or Repeater
Layer 2 (Central Hub)
Switch or Bridge
Layer 3 (Central Hub)
Router or Gateway
a host is connected to one or multiple hosts
Mesh Topology
is smallest network which is very personal to a user.
Personal Area Network
has connectivity range up to 10 meters.
Personal Area Network
a computer network spanned inside a building and operated under single administrative system.
Local Area Network
covers an organization offices, schools, colleges or universities.
Local Area Network
is most widely employed LAN technology and uses Star Topology while Token-Ring is rarely seen.
Ethernet
is a family of computer networking technologies commonly used in local area networks, metropolitan area networks, and wide area networks.
Ethernet
generally expands throughout a city such as cable TV network.
Metropolitan Area Network
covers a wide area which may span across provinces and even a whole country.
Wide Area Network
a network of networks is called?
Internetwork
is the largest network in existence on this planet.
Internetwork
Types of Networks
- Instant Messaging
- Blogging
- Social Media
- Marketing
- Networking
- Resource Sharing
- Audio and Video Streaming
is an open standard for all communication systems.
OSI Model
OSI Model (7 Layers)
- Application Layer (Layer 7)
- Presentation Layer (Layer 6)
- Session Layer (Layer 5)
- Transport Layer (Layer 4)
- Network Layer (Layer 3)
- Data Link Layer (Layer 2)
- Physical Layer (Layer 1)
This layer is responsible for providing interface to the application user.
Application Layer
This layer defines how data in the native format of remote host should be presented.
Presentation Layer
This layer maintains sessions between remote hosts.
Session Layer
This layer is responsible for end-to-end delivery between hosts.
Transport Layer
This layer is responsible for address assignment and uniquely addressing hosts in a network.
Network Layer
This layer is responsible for reading and writing data from and onto the line.
Data Link Layer
This layer defines the hardware, cabling, wiring, power output, pulse rate etc.
Physical Layer
internet uses TCP/IP protocol suite, also known as _______?
Internet Suite
TCP/IP means?
Transmission Control Protocol/Internet Protocol
is the transport/network layer protocol used in the internet.
TCP/IP
allows reasonably efficient and error-free transmission.
TCP/IP
is the principal communications protocol in the internet protocol suite for relaying datagrams across network boundaries.
Internet Protocol
is responsible for addressing host interfaces, encapsulating data into datagrams.
Internet Protocol
is one of the main protocols of the internet protocol suite.
TCP
any network could connect to another network through a gateway.
Network Connectivity
there would be no central network administration or control
Distribution
lost packets would be retransmitted
Error Recovery
no internal changes would have to be made to a network to connect it to other networks.
Black Box Design
is set of communications protocols used on the internet.
Internet Protocol Stack/Suite
is a set of rules for exchanging information over a network
Communication Protocol
defines TCP/IP application protocols and how host programs interface with Transport Layer Services to use the network.
Application Layer
when applications open a connection to another computer on the internet, the messages they send get passed down the stack to the TCP layer.
Transport Layer
the unique number ID assigned to one host or interface in a network.
Address
a portion of a network that shares a particular subnet address.
Subnet
a 32-bit combination used to describe which portion of an address refers to the subnet and which part refers to the host.
Subnet Mask
a network connection.
Interface
is a numerical label assigned to each device connected to a computer network that uses the Internet Protocol for communication.
IP Addresses
used to identify systems on a TCP/IP network.
IP Addresses
each 8 bit group is known as ______?
OCTET
identifies the physical network to which the computer is attached
Prefix
identifies an individual computer on that network
Suffix
the network prefix is indicated by a _____?
Netmask
manually input by network administrator
Static Address
assigned by server when host boots
Dynamic Address
derived automatically from a range of addresses
Dynamic Address
BOOTP means?
Bootstrap Protocol
DHCP means?
Dynamic Host Configuration Protocol
each link connects two entities.
Nodes
is a set of connected devices.
Network
is a set of nodes that are interconnected to permit the exchange of information.
Network
is either a redistribution point or a communication endpoint.
Nodes
any system or device connected to a network is also called a?
Node
consists of series of interlinked nodes
Switched Network
is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device.
Switches
is the term used to describe communication where a piece of information is sent from one point to another.
Unicast
in which a packet is sent from a single source to specified destination.
Unicast Transmission
sometimes referred to as connectionless networks?
Datagram Networks
is a cross between a circuit-switched network and a datagram network.
Virtual-Circuit Network
is collection of data that can be used by computers which need to communicate with each other.
Packets
consists of control information and user data which is also known as?
Payload
is the most familiar technique used to build a communication network
Circuit Switching
consists of a set of switches connected by physical links.
Circuit Switching
a connection between two stations is a dedicated path made of one or more links.
Circuit Switching
after the establishment of the dedicated circuit the two parties can transfer data.
Data Transfer Phase
when one of the parties needs to disconnect, a signal is sent to each switch to release the resources.
Teardown Phase
the paths in the circuit are separated from one another spatially.
Space Division Switch
connects n inputs to m outputs in a grid, using electronic micro switches (transistor) at each cross point.
Crossbar Switch
which combines crossbar switches in several stages.
Multistage Switch
is most often used for data communication.
Packet Switching
allow multiple signals to be sent over a single faster connection by sectioning a link into time slots.
Multiplexing
one layer of a host deals with the task done by or to be done its peer layer at the same level on the remote host.
Layered Task
is the process of verifying the received information whether it is correct or not at the receiver end without having any information of sent original message.
Error Detection
