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networkingchpt.7
terms
Question | Answer |
---|---|
wan | network that traverses some distance and usually connects lans |
wan | network transversing some distance |
wan and lan common properties | client host resource sharing |
layer three and higher protocols | |
packet switched digitized data | |
lans and wans | |
adsl | a variation of dsl that offers more throughput when data travel downstream,downloading from a local carriers switching facility to the customer,that when data travel upstream,uploading from the customer to the local carriers switching facility |
asymmetrical | the characteristic of a transmission technology that affords greater bandwidth in one direction than in the other direction,customer to the carrier or vice versa |
asynchronous | a transmission method in which data being transmitted and received by nodes do not have to conform to any timing scheme. |
atm | asynchronous transfer mode |
atm | data link layer technology.relies on fixed packets called cells that consist of forty eight bytes plus a five byte header |
atm | relies on virtual circuits and establishes a connection before send |
b channel | bears traffic from point to point |
bri | basic rate interface |
bonding | process of combining more than one bearer channel of an isdn line to increase throughput |
bpl | broadband over powerline |
bri | a variety of isdn that uses two 64 kbps bearer channels and one 16 kbps data channel |
bri | most common form of isdn employed by home users |
wan and lan differences | layer 1 and 2 access methods,topologies,media |
wan and lan differences | lan wiring,privately owned |
wan and lan differences | wan wiring:public thru network service providers,ex.at&t |
broadband cable | a method of connecting to the internet over a cable network |
lan topologies differences | distance covered,number of users,traffic |
lan topologies differences | connect sites via dedicated high speed links |
broadband cable | computers are connected to a cable modem that modulates and demodulates signals to and from the cable companys head-end |
bus topology wan | each location is connected to no more than two other locations in a serial fashion |
cable drop | the fiber optic or coaxial cable that connects a neighborhood cable node to a customers house |
bus topology wan | each site connects serially to two sites maximum |
bus topology wan | network site dependent on every other site to transmit and receive traffic |
bus topology wan | different locations connected to another thru point to point links |
bus topology wan best use | organizations requiring small wan dedicated circuits |
bus topology wan drawback | not scalable |
cable modem | a device that modulates and demodulates signals for transmission and reception via cable wiring |
cell | a packet of fixed size |
cir | committed information rate |
cir | the guaranteed minimum amount of bandwidth selected when leasing a frame relay circuit |
co | central office |
ring topology wan | each site connected to two other sites |
ring topology wan | forms ring pattern |
ring topology wan | connects location |
ring topology wan | relies on redundant rings |
ring topology wan | data rerouted upon site failure |
ring topology wan | expansion is difficult and expensive |
ring topology wan best use | connecting maximum five locations |
co | the location where a local or long distance telephone service provider terminates and interconnects customer lines |
star topology wan | single site as central connection point |
star topology wan | seperate data routes between any two sites |
star topology wan | single connection failure affects one location |
star topology wan | shorter data paths between two sites |
star topology wan | expansion is simple and less costly |
star topology wan | |
star topology wan | |
csu | channel service unit |
mesh topolgy wan | incorporates many directly interconnected sites |
mesh topolgy wan | data travels directly froom origin to destination |
mesh topolgy wan | routers can redirect data easily,quickly |
mesh topolgy wan | most faulerant type of wan |
mesh topolgy wan | every wan is directly connected to every other site |
mesh topolgy wan | expensive |
csu | a device used with t carrier technology that provides termination for the digitsl signal and ensures connection integrity thru error correction and line monitoring |
csu/dsu | channel service unit and data service unit |
csu/dsu | serves as the connection point for a t1 line at the customers site |
csu/dsu | may be a seperate device or an expansion card in another device such as a router |
d channel | in isdn the data channel is used to carry information about the call,such as session initiation and termination signals,caller identity,call forwarding and conference signaling |
dedicated | a continuously available link or service that is leased by another carrier |
tiered topology wan | sites that are interconnected in star or ing formation,interconnected at different levels |
tiered topology wan | interconnection points organized into layers,form hierarchial groups |
tiered topology wan | flexible,many variations |
tiered topology wan | requires careful considerations,geography,usage patterns |
tiered topology wan | |
dialup | a connection in which a user connects to a distant network from a computer and stays connected for a finite period of time |
pstn | |
pstn | network of lines,carrier equipment providing telephone service |
pstn | plain old telephone service |
pstn | encompasses entire telephone system |
downstream | data traffic that flows from a carriers facility to a customer |
ds0 | digital signal level 0 |
ds0 | the equivalent of one data or voice channel in t carrier technology |
dsl | digital subscriber line |
dsl | a dedicated wan technology that uses advanced data modulation techniques at the physical layer to acheive extraordinary throughput over regular phone lines |
pstn elements | cannot handle digital transmission |
dslam | dsl access multiplexer |
local loop | last mile |
local loop | portion of the pstn that connects any residence or business to the nearest central office |
niu | network interface unit |
niu | the point at which pstn owned lines terminate at a customers premise |
ftth | fiber to the home |
ftth | telephone company connects residential users to its network with fiber optic cable |
fttp | fiber to the premises |
fttp | the use of a fiber optic cable to connect either a residence or a business |
pon | passive optical network |
pon | a carrier uses fiber optic cabling to connect with multiple endpoints |
olt | optical line terminal |
olt | device with multiple optical ports similar to interfaces on a router |
onu | optical network unit |
onu | distributes signals to multiple end poins via fiber optic cable |
x.25 | analog packet switching technology designed for long distance transmission |
x.25 standard specifies protocols at the | physical,data link, and network layers of he osi model |
x.25 | provides excellent flow control and ensures data reliability by verifying the transmission at every node |
frame relay | digital version of x.25 that relies on packet switching |
frame relay | protocols operate at the data link layer |
frame relay | seperated into frames which are then relayed from one node to another without any verification or processing |
frame relay | does not guarantee reliable delivery of data |
virtual circuits | |
svc | switched virtual circuits |
svc | |
pvc | permanent virtual circuits |
pvc | |
svc are connections | that are established when parties need to transmit then terminate after the transmission is complete |
pvcs are connections | |
isdn | integrated services digital network |
isdn | transmitting digital data over the public switch telephone network |
isdn specifies protocols | physical,data link,and transport layers of the osi model |
protocols handle | signaling,framing,connection setup and termination,rouing,flow control,and error detection and correction |
isdn can carry | as many as two voice calls and one data connection on a single line |
isdn channels | b and d channel |
single b channel maximum throughput | 64 kbps |
single d channel maximum throughput | 16 or 64 kbps |
data channel | employing packet switching techniques to carry information about the call |
bearer channel | employing circuit switching techniques to carry voice,video,audio,and other types of data |
isdn connections | bri and pri |
bri | uses two b channels and one d channel |
bri | most economical type of isdn connection |
nt1 | network termination |
nt1 | |
te | terminal equipment |
ta | terminal adapter |
ta | converts digital signals into analog signals for use with isdn phones and other analog devices |
primary rate interface | |
network termination 2 | |
bonding | |
disadvantage of isdn | span a distance of only 18,000 linear feet before repeater equipment is needed to boost the signal |
t-carrier | standards specify a method of signaling which means they belong to the physical layer of the osi model |
t carrier | uses time division multiplexing |
t1 circuit | carry the equivalent of 24 voice or data channels,giving a maximum of 1.544 mbps |
t3 circuit | carry the equivalent of 672 voice or data channels,giving a maximum of 44.736 mbps |
speed of a t carrier | depends on its signal level |
signal level | |
ds0 | |
fractional t1 | an arrangement that allows a customer to lease only some of the channels on a t1 line |
smart jack | a termination for t carrier wire pairs that is located at the customer demarc and which functions as a connection protection and monitoring point |
csu/dsu | connection point for a t1 line |
csu provides | termination for the digial signal and ensures connection integrity thru error correction and line monitoring |
dsu provides | converts the t carrierframes into frames the lan can interpret and vice versa |
multiplexer | a device that seperates a medium into multiple channels and issues signals to each of those subchannels |
dsl | digital subscriber line |
dsl | wan connection method |
dsl | uses data modulation techniques at the physical layer to acheive extraordinary throughput over regual phone lines |
types of dsl | adsl, g.lite,hdsl,sdsl,vdsl,shdsl, |
asymmetrical dsl | offers more throughput in one direction than another |
downstream | data traveling from the carriers switching facility to the customer |
symmterical | provides equalcapacity for data traveling both upstream and downstream |
upstream | data traveling from the customer to the carriers switching facility |
dsl modem |