chptr12

Question 1

Data

Answer 1

Messages between sender / receiver

Question 2

Communications Channel

Answer 2

Path for messages between 2 nodes
may include intermediate nodes that forward packets
interfaces at each end may be different

Question 3

Protocols

Answer 3

Establishes accurate and appropriate meaning to messages

Question 4

Physical Connection

Answer 4

Independent of the messages

Question 5

Hosts & end nodes

Answer 5

sender and receiver end points

Question 6

Message

Answer 6

primary purpose of communication - data - program - file - multimedia - represented digitally

Question 7

byte stream

Answer 7

term used with data as communications are predominately serial

Question 8

Packets

Answer 8

Long messages broken down to help with channel availability
takes turns using channels
some can be identified as frame or datagram to identify purpose
Header followed by data
1A, 1B, 1C etc

Question 9

Links

Answer 9

Segment of communication channel

Question 10

Bandwidth

Answer 10

Bit rate of overall channel

Question 11

Medium Guided

Answer 11

communications limited to specific path

Question 12

Medium Unguided

Answer 12

Not limited to specific path

Question 13

End Node Interfaces

Answer 13

Wired - Wireless Ethernet - Bluetooth - WiMax - DSL - Cable - Sat Link - Modem etc

Question 14

Network Topology

Answer 14

Fundamental Layout of Netork
describes path between 2 points
affects availability, speed and traffic

Question 15

Logical Topology

Answer 15

Operational relationship between the various network components

Question 16

Physcial Topology

Answer 16

Actual layout of the network wiring

Question 17

Mesh Topology

Answer 17

Multiple paths between end nodes
1 node failure will slow but not stop as long as other path is available
large networks that use switches & routers are typically partial mesh

Question 18

Full Mesh Network

Answer 18

Direct Point 2 Point channel connecting every pair of nodes

impractical due to large number of connections needed

Question 19

Bus Topology

Answer 19

Each node is tapped into the Bus along the Bus
node broadcasts a message that travels the entire bus
every node receives but ignores if not addressee
travels entire medium both directions
termination required at ends of bus to prevent echoing
branches can be added to create tree but still wide broadcast

Question 20

Bus Network Implementation

Answer 20

req single pair of wires from one end of network to other
cheap - easy to wire
rarely used in new networks except for wireless nets

Question 21

Star Topology

Answer 21

Primarily for LANS & sometimes connecting satellite offices to central
all nodes connected to a point 2 point device
nodes communicate through central device
switching in central device connects 2 nodes together
central device can steer data from one node to another as req
most modern switches allow mult pairs simultaneously
Failure of central device will kill entire network

Question 22

Ring Topology

Answer 22

Point 2 Point connection from each node to next
Last node connects to first to create ring
nodes forward messages in loop unidirectional (bidirectional is possible tho)
past popularity ie token ring

Question 23

Local Area Networks LAN

Answer 23

Network that connects computers etc over a small localized area

Question 24

Wide Area Network WAN

Answer 24

networks over large distances

Question 25

Extranet

Answer 25

connection between a business and a business partner

Question 26

PSTN Public switched telephone networks

Answer 26

large cable companies and other common carrier providers

Question 27

Private virtual circuits

Answer 27

logical connections of the WAN as a whole

Question 28

Hub

Answer 28

is a central connection device used to simplify wiring

Question 29

hub based ethernet

Answer 29

similar to star topology but not smart - it's passive

Question 30

service provider

Answer 30

Provides internet connection

Question 31

wi fi

Answer 31

radio based compativle extension to ethernet standard

Question 32

switched ethernet

Answer 32

based on star topology, each node connected to central switch that is capable of connecting any 2 nodes together.

Question 33

backbone networks

Answer 33

used to interconnect several LANs

Question 34

hierarchical LAN

Answer 34

higher up the backbone network

Question 35

Routers and gateways

Answer 35

intermediate link connecting nodes from various networks. Converts data format to the next required. Specialized device to interconnect networks and pass packets.

Question 36

mesh points

Answer 36

extends the range of wireless networks

Question 37

intranet

Answer 37

web services that are restricted to a group of users

Question 38

Metropolitan Area Network MAN

Answer 38

network larger in geographical scope than a LAN but within a range of less than 30 miles.

Question 39

edge & edge router

Answer 39

a router at the edge of the local network, a router would be an edge router

Question 40

point of presense

Answer 40

ISP has a point of presence in the immediate vicinity to connect to.

Question 41

Internet backbone

Answer 41

Large ISPS known as national or internation service providers to speed traffic

Question 42

Network Access Points NAPS

Answer 42

Interchanges on the internet backbone

Question 43

Piconets or Personal Area Netowrks PANS

Answer 43

separate from other networks, these are created for the presonal use of an individual with a range of 30 ft or less

Question 44

Packet Routing

Answer 44

packets are passed along the links from node to node.

Question 45

circuit switching

Answer 45

dedicates a path for exclusive use of the sender receiver pair for the entire length of time of the connection. Inefficient and rarely used

Question 46

virtual circuit

Answer 46

multi link channel path established for communication between 2 end nodes

Question 47

permanent virtual circuit PVC

Answer 47

virutal circuit that is created when a network is built

Question 48

Switched virtual circuit SVC

Answer 48

set up temporarily when a connection is esablished and maintained until the connection is closed

Question 49

packet switching

Answer 49

aka datagram switching assumes that each packet is routed from node to node independently - shortest path to destination - less traffic