ch Flashcards
what is telecommunication?
communication at a distance.
what are the component of the data communication?
- message
2.sender - receiver.
- medium
- protocol
what are the characteristics of the effective data communication?
1.deliverable: deliver to the right destination.
2. accuracy: deliver the data accurately.
3. timeliness: deliver the data in a timely manner
4. jitter: variation in packet arrival time
what are the types of the data flow?
- simplex mode
- half duplex mode
- full duplex mode
what is the simplex mode?
the data goes in one way only
what is the difference of using half duplex or full duplex?
half duplex: the data can be transfer in both direction but not at the same time. whereas in the full duplex the data can transfer in both direction and in the same time
what is the network?
a set of devices connected by a communication link.
what are the network criteria’s?
- performance: 1-transit time, 2- response time, number of users
- reliability: frequency of failure, how long it takes to recover from failure.
3.security: protecting data from authorized access
what are the types of networks connection?
- point to point
- multipoint
what is the topology of network?
a geometric representation of the relationship between the links and linking devices to one another.
types of topologies:
- mesh
- star
- bus
- hyperd
- ring
what is mesh topology?
every device has a didcated point to point link to every other node
what is the advantages of using mesh topology?
- guaranteed load
- robust
- security and privacy
- fault identification
- fault isolation is easier
what are the disadvantages of using mesh topology?
- I/O installation is difficult
- expensive hardware
- more wiring with respect to space
- amount of caples required
what is star topology?
every device has a dedicated point to point link with the hub.
no direct connection or traffic
what is star topology?
every device has a dedicated point-to-point link with the hub.
no direct connection or traffic
what are the advantages of using star topology?
- less expensive
- one link and one I/O port
- less cabling but more than the bus and ring
- node failure will not affect others.
- fault identification is easy
- easy to install and conifigure
what is the disadvantage of star topology?
a single point-to-point failure.
what is the bus topology?
multipoint: one cable acts like the backbone links all devices to the network.
what are the advantages of using bus topology?
- less cabling
- easy to install
what are the disadvantages of using bus topology?
- limitation on number of tabs and the distances between each tabs.
- difficult to identify the fault
- modification is difficult
- single degradation
what are the advantages of using ring topology?
- easy to install
- fault isolation is easier
- single circulates at all times
what are the disadvantages of using ring topology?
- break the ring discard all the network
- unidirectional traffic
categories of network:
- size
- ownership
- distance it covers
- physical architecture.
what is LAN?
- privately owned
- few kilometres.
- link devices in local office, and campus.
- use a single transmission media
- topology: ring, bus, star
what is MAN?
- extended over an entire city
- owned by a private company
- service provider
what is WAN?
- owned by the enterpriser network
what are the types of WAN?
- switched WAN: network with more than two ends
- a point to point WAN: a network that connects two communication devices through a transmission media
what is the Heterogeneous network?
a network which made of 4 WANs and 2 LANs
what is circuit switching network?
- it has dedicated connection, always between two end systems
- the switch can only make active or inactive
what is the packet switching network?
- the communication is done in blocks of data called packets.
- it uses a router to store and forward the packets.
