Wifi

Question 1

Co je CSMA/CA?

Answer 1

Carrier Sense Multiple Access with Collision Avoidance
ak sa na frekvencii nieco deje tak cakame na ticho
po tichu pockam nahodny cas
ak stale ticho, vysielam

Question 2

Na akej vrstve potvrdzuje Wifi prijem ramca?

Answer 2

Na linkovej vrstve

Question 3

Ake adresy pouziva WIFI?

Answer 3

Rovnake ako Ethernet

Question 4

RTS/CTS ako funguje

Answer 4

When a node wants to transmit data to another node, it sends out a RTS ‘Request to Send’ packet. The receiver node replies with a packet called CTS ‘Cleared to Send’ packet.After the transmitter node receives the CTS packet, it transmits the data packets

Question 5

Aka je najviac vykonna verzia Wifi?

Answer 5

802.11n

Question 6

Pre 802.11n v akej frekvencii vie ist?

Answer 6

2.4 aj 5 GHz

Question 7

Aka je max rychlost 802.11n?

Answer 7

300 Mb/s

Question 8

Aka je najmensia verzia Wifi?

Answer 8

802.11b

Question 9

Co je BSS?

Answer 9

Basic service set
mnozina stanic tvoriaca zakladnu bunku siete
napr. access point a niekolko stanic

Question 10

Co je ESS?

Answer 10

Extended service set

mnozina BSS

Question 11

Co je ESSID?

Answer 11

identifikator ESS

Question 12

Z coho sa sklada infrastruktura wifi?

Answer 12

AP - access point
DS - distribucny system
portal

Question 13

Na co sluzi access point?

Answer 13

Stanica sa asociuje k AP

zabezpecuje prenos ramcov medzi stanicami a DS

Question 14

Na co sluzi distribucny system?

Answer 14

Prepaja AP tvorice ESS

umoznuje roaming medzi BSS

Question 15

Na co sluzi portal?

Answer 15

Prepaja ESS s inou sietou

Question 16

Co je ad-hoc rezim?

Answer 16

Niekolko stanic tvoriace siet
Nema pristup k DS
nepotrebuje AP

Question 17

Kolko kanalov maju prve WIfi verzie?

Answer 17

13+/-