Karteikarten
ICT
Karten in diesem Stapel (168)
- 1Life Cycle of network developmentneeds analysis
network design
network set-up
testing and debugging
maintenance
user training and support - 2collect what information of existing network environmentinterview basic needs, budgets, reliability, compatibility, scalability
- 3documents in network developmentrequirement specification
- 4what are the network modelspeer to peer P2P
client-server model
small office house office SOHO - 5Component of networkfile server, login, print, internet
- 6Advantages and disadvantages of network modelcost, maintenance, client power, ongoing support, scalability, security, managability
- 7file servers + specificationsfile server + backup: read write fast, enough storage capacity, scalable, robocopy
- 8domain controller + specificationsdomain controller: reliable and stable
- 9all serversfile server, domain controller, app server, web server, print server, dhcp
- 10web server + specificationsweb server: outside firewall
- 11print server + specificationsPrint server: enough ports
plug-in cards: JetDirect card - 12DHCP + specificationsDHCP: fix IP address, avoid IP
- 13app server specificationsapplication server: extensive cpu, concurrent access and bandwidth
- 14why are domain controllers hard to be infectedonly login information like login name and passwords is transmitted
- 15what to consider of OScost for license
official support
extra training
language version - 16how to treat web server files in file serverput in demilitarized zone
- 17how to establish a virtual connectionleased line, VPN, virtual IP
- 18modes in router osuser executive mode
privileged executive mode "en"
global configuration mode "conf t"
other specific configuration mode "int fa0/0" - 19What do we test in systemFunctionality testing
performance testing
stress testing: maximum load of network is reached
Recovery testing: perform backup and recovery plans
security testing - 20User acceptance test UATusers in front end to see if meets user requirements
training + signature - 21what are the test activitiestest environment identification
acceptance criteria identifcation
test planning and design
test environment configuration
test execution
result analysis, debugging, retesting
reporting - 22what are the testing documentstest plan: introduction, test items + features, approach, criteria, environmental needs, responsibility (in charge), schedules
- 23what are the 4 main concerns of securityconfidentially: private
integrity: no data lost
authentication: receiver identify
non-repudation: sender identify - 24what are bad guys able to do to the packetview and edit
- 25what are the 2 encryption keyssymmetric keys, asymmetric keys PKI
- 26What is symmetric key and what are the advantages and disadvantagesExchange keys before sending
Adv: faster encryption process
Dis Adv: store a lot of keys - 27What is asymmetric keypublic key, private key (digital signature) with CA
peer to peer
biometric measure/ pretty good privacy PGP - 28what is inside firewallfirewall rules
filter table - 29sharing of resources in networkhardware software
data bandwidth - 30client servers architecturefile server, ftp server
- 31calculating the number of peer to peer linesnC2
- 32what to write in test specifications and reportSpecification: test design, cases, procedures
Report: test log, incident report, summary report - 33User traininglet them familiarize the functions and regulations
- 34user supporttroubleshoot, help desk
- 35what is in the support documentsuser manual
FAQ
troubleshooting guide - 36what documents in maintenance phasenetwork diagram
- 37network managementfault, performance, configuration, user account, security
monitoring, testing, troubleshooting
to provide quality of service QoS - 38what are the 2 fault managementproactive fault management: fault prevention, update service packs, develop disaster recovery plan
Reactive fault managment: troubleshooting - 39what is performance managementmanage the performance ensure it is running smoothly and efficiently
- 40configuration managementdo reconfiguration when changes to network happens, like replacing DNS
- 41is it good to have same admin account for all adminshard to see who made mistakes
- 42SNMPsimple network management protocol
an agent runs on managed devices to report the performance to the manager via SNMP, a management database stores the performance
GET (retrieve information)
SET (change configuration)
TRAP (actively report events) - 43what does GET and SET and TRAP doGET (retrieve information)
SET (change configuration)
TRAP (actively report events) - 44troubleshooting toolsping, tracert, netstat
event viewer, network monitor, cable tester, time-domain reflectometer - 45disaster solutionsdisaster planning: proactive after disaster happens
disaster recovery: resume operations - 46components of backupbackup medium: second storage medium
backup and recovery: software perform backup and recovery
backup server: do all the stuff above - 47how to config multiple pc at the same timecreate ghost image and clone
- 48backup typesfull (all data)
differential (weekday accumulate) incremental (only that day)
partition backup of disk - 49fault tolerance solutionsUninterruptible Power Supply UPS
Offline UPS: connected standy power supply
Online UPS: middle of cable and server - 50RAIDRedundant Array of Independent Disk RAID
RAID 1 mirror data to other disk
RAID 5 disk stripping with parity - 51security threatsmalware, unauthorized access, interception, denai of service DoS
- 52what are computer virusesreplicate itself to another document, program or pc boot sector/ sytem files (file infector, macro viruses, system or boot-record infector)
if theres a medium
infection phsae and attack phase - 53what are wormspropagate across network
if theres security loopholes - 54what are trojan programsdisguise as legitmate program using fake file extension
they do not replicate, harder to detect - 55what are spywarerun in background and collect information
pop up advertisement, change system settings like new tab
they do not replicate - 56common ways of virus appearanceinfected files, drive-by download, piggybacked software installation
- 57what is hackingunauthorized access
attempt connection without permission
to view private condifential data (private)
operations like delete, edit, config - 58hacking methodsvulnerability scanning, port scanning, key logging, phising, social engineering, brute force attack
vulnerability scanning: find bugs in system
port scanning: find open port in transport layer like TCP UDP ports
key logging: log keys striked by user in keyboard
phishing: trick user to give credit informations using spam or fake web site
social engineering: ask the client
brute force attack: dictionary attack or packet sniffing, password attempts, usually set attempt limits or change password period - 59what is packet sniffing and how to preventcapture packets travelling
prevent with encryption
network sniffer NIC pick up traffcs - 60what is denial of service DoSflood network with data
service unavailable to normal users - 61what are the network security measuresanti-virus, authentication, access and user right control, firewall, intrusion detection system, encryption, internet protocol security IPSec, virtual private network VPN, wireless security protocols
- 62anit-virus software technologyanti-virus engine and virus signature file
Signature scacnning: dead list to identify malware, must update frequently
Heuristics: detect new malware not in list by their characteristics - 63how to handle malwarerepair, delete or quarantine (isolate)
- 64what is intrusion detection systemdetect suspicious intrusion in network by monitor network traffice and log files
host-based, network-based - 65what is IPSecinternet protocol security
it handles the encryption and authentication of IP packets
"encrypter" - 66what is vpnfacilitate secure connection between private networks through Internet
inexpensive, flexible - 67wireless security protocolsWired Equivalent Privacy WEP
wi-Fi Protected Access WPA, stronger encryption - 68user access control measurestoken based authentication
human verification - 69IPOInput Process Output
- 70Data vs informationdata: raw fact that are not organised and have no meaning
information: organised, meaningful and for decision making - 71text codescharacter coding system
eg. ASCII, Unicode, Big5
handwriting board and scanner with optical recognition OCR - 72image typesvector
bitmap
eg. png jpg - 73personnelsystem analyst: plan and implement system
programmer: convert system design into program
technician: backup, monitor resource usage
network manager: monitor network performance
data entry operator
help desk: troubleshooting - 74information processesdata collection
organization
storage
processing
analysis
transmission
presentation - 75information agepc become essential tool for communication
access to information anywhere - 76knowledge based societyemploy knowledge, information technology and communication system to process of all walks of life
PC, communication network, and people - 77information literatedetermine the nature of information needed
question source of information
use information ethically and legally - 78GIGOgarbage in garbage out
- 79source of data input errordata source error
transcription error (typed)
transposition error (swap space) - 80data validation vs data verificationdata validation: reasonable
data vertification: input data match source
repeat password - 81data validation methods@1234567890.com [14][0-9][Select][Number abc symbol allowed]
field presence
field length
range check
fixed value check (select)
format check
type check
parity check ISBN - 82ISBNcheck digit/ parity check
_ _ _ _ _ _ _ _ _ _
group | publisher | title | check digit - 83database system hierachyfield, record, table, database
vlookup - 84DBMSDatabase management system
write, edit, read data - 85what are the file access modessequential access mode: one by one, long seek time
direct access mode: high reliability, speed and capacity - 86PNG vs JPGPNG: mainly for text, graphics
JPG: drawings - 87audio qualitybit resolution and sampling rate
- 88analogue data to analogue signalsmodulation
- 89Digital Data -> Analogue SignalsModulation & demodulation
- 90Data -> SignalEncoding & Decoding. Error detection can be added to enhance the reliability of data transmission
- 91Analogue Data -> Analogue SignalIn radio broadcast, (Ex: AM, FM)
- 92Analogue data -> Digital SignalsDigitization (Ex: PCM)
Sampling and quantization - 93Digital Data -> Digital SignalsLine Coding & Decoding
- 94Line Coding & DecodingDigital Data -> Digital Signals
- 95DigitizationAnalogue data -> Digital Signals
- 96BroadcastingAnalogue Data -> Analogue Signal
- 97line codingDigitzation
polar nrz
polar rz
manchester - 98what are the 4 error detection methodschecksum
parity check
cyclic redundancy check CRC
codeword - 99CRCcyclic redundancy check CRC
long division of polynomial
detect burst error - 100TCP/ IP reference modelapp
transport
internet
host to network - 101what are the protocols for application layerFTP, Telnet, SMTP, HTTP, DNS
- 102HTTPhypertext transfer protocol
translate text into IP address - 103what are the protocols for internet layerTCP, UDP, SCTP
- 104what are the protocols for transport layerIP, encryption IPSec
- 105what are the protocols for host to network layerOptical fibre, twisted pair cable
- 106benefits of using tcp/ tp reference modelchange made in one layer wont affect other layers
reduce time for troubleshooting - 107what is inside headersource, destination address
checksum - 108TCPconnection oriented service
end to end communication establishment
able to full-duplex communication
connection terminate after transmission - 109TCP functionserror control (discard corrupted, duplicated and retransmit lost)
flow control (switch to smaller bandwidth for receiver)
congestion control (network load more than capacity) - 110UDPunreliable
- 111SCTPvoice over the internet in application layer
VoIP - 112IPbest effort delivery
connectionless (packet travel different path)
TTL time-to-live (value drop 0, prevent looping) - 113NATnetwork address translation NAT
translate private address into public
or port address translation PAT - 114what are the network, broadcast, localhost and link-local address of a networkNetork: 192.168.0.0
Boradcast: 192.168.0.255
localhost: 127.0.0.1
link-local: 169.254.0.0 (happens when no IP is assigned) - 115IPv6 advantageslarger address space
IPSec integration, more secure
priotize network traffic (background data, interactive traffic and real time av) - 116NICnetwork adaptor card NIC
allow pc to communicate with each other
eg. ethernet, token ring, power line, wireless network - 117Twisted-pair cablesMade of: plastic insulated conductors
Use: reduce electromagnetic interference EMF
reduce cross talking from neighouring wires - 118Shielded twisted pair cablesMade of: higher cost
Use: reduce potential disturbance - 119what connection use straight through wirerouter to switch/ hub to pc
- 120what connection use cross-over cablesame thing
router to pc - 121rollover cableconnect router for terminal program for configuration
- 122coaxial cableMade of: Alumiminium, plastic cover
Use: legacy ethernet network - 123optical fibre cableMade of: light transmission
Use: backbone of network
Advantages: high speed and long distance transmission
more secure, immune to tapping
less interference - 124optical fibre cable modessingle mode: laser, single beam
multimode: LED, multiple beam - 125why are wireless transmission not that securemore sensitive to interference
- 126what are the three kinds of transmission wavesradio wave, microwave, infra red
- 127higher frequency pass through walls easily?no
lower frequency can travel longer distance and penetrate walls - 128radiowavelow frequency long distance and penetrate walls
Use: radio AM FM broadcast - 129microwavelow frequency long distance and penetrate walls eg 2.4Hz 5Hz
Use: WiFi, satellites + cellular phone - 130infra-redhigh frequency, close range, cannot penetrate walls
Use: remote controller, IrDA devices - 131repeater vs hubRepeater: amplifies signal received to travel farer
does not examine
Hub: send to all ports, NIC auto drop packets - 132features of switchwhat: determine packets destination by their MAC address in a table (forward and filtering), which builds up (address learning)
Use: reduce data collision due to forwarding one port (performance evaluation) - 133bridgeWhat: divide large network into smaller segment
Use: forward broadcast message to all connected network - 134routerWhat: forward packets to other network
Advantages: enhance network security cuz block unwanted traffic, broadcasting message cannot pass through router - 135State 2 ways of routing their adv and dis advStatic routing: manual set destination network
Disadvantage: error easily, not flexible and scalable
Dynamic routing: determine destination according to real time situation: distance vector and link state
distance vector: less distance and hops
link state: less hop, link speed, congestion
keep map of whole network, updates when link state change - 136what is distance vector and link statedistance vector: less distance and hops
eg. RIP
[more real-time] link state: less hop, link speed, congestion
keep map of whole network, updates when link state change
eg. OSPF - 137APaccess point/ wireless router
connect wireless device to form wireless network
connect to wired network form hybrid network - 138modemconnect internet through existing telephone network
- 139what is the standard for ethernetIEEE standard 802.3
10Mb - 100Mb - 1Gb - 10Gb
- physical bus topology
Standard ethernet: 10Mb
fast ethernet: 100Mb
- full-duplex, optical fibre
Gigabit ethernet
Ten-gigabit: - 140CSMA/ CDCarrier sense Multiple access Collsion detection CS MA CD
Carrier sense: listen medium before sending
Multiple access: allow multiple pc to access medium
Advantage: reduce data collision
Collision detection: back-off period before sending again
abort after number of tries - 141ARPaddress resolution protocol ARP
translate IP into MAC
RARP - 142PLCpower line communication PLC
Homeplugs to NIC
Advantages: no extra wire
easy to install - 143roamingstay connected even device move from one network coverage to another
- 144SSIDservice set identifier SSID
WiFi name - 145wireless standards802.11 a b g n ac
- 146BSSbasic service set BSS
basic building block of WLAN - 147wireless architectureAP: infrastructure network
no AP: ad hoc network
wireless wired: hybrid network
BSS + AP at backbone: extended service set ESS - 148CSMA CAbefore sending wait for specific time
acknowledgement frame is send back - 149WiFi hotspot networksole purpose is provide internet access
- 150GPRSgeneral packet radio service GPRS
mobile phone networking transmission
2.5G mobile technology - 151HSPAhigh speed packet access HSPA
3.5G - MAN/ WAN
HSDPA modem/ SIM card to use service - 152WiMAXradio signal
- 153What are the protocols for wirelessWiFi, Bluetooth, WiMAX, satellites
- 154P2Ppeer to peer P2P
What: no centralized resource
Advantages: little cost
less network knowledge needed
Disadvantage: less secure
difficult network administration - 155NASnetwork attached storage
multiple access
file storing
or for backup - 156file server advantages disadvantagesadv: centralized administration save time
Dis Adv: server grade high cost - 157domain controller advantages disadvantagesAdv: centralized administration
Dis Adv: server grade high cost
unable to login, single point pf failure - 158DHCP advantages disadvantagesAdv: save time for IP address assigning
centralized administration
avoid and reuse IP address
Use: roaming
Dis Adv: server grade high cpst
not IP address assigning, single point of failure - 159proxy server advantages disadvantagesAdv: more secure, no identity expose
reduce network traffic and latency of cached data (downloaded before)
filter indecent material
Dis Adv: no internet, single point of failure - 160measures against spamnever reply to junk email
spam filtering software - 161problem create by spamoccupy storage
take time to remove
flooding slow down network traffic - 162ways to maintain privacyanonymous
browse trusted website
internet service provider ISP record packets
use proxy server
safeguard strong password, change
security anti spy mal ware software - 163SSLsecure socket layer SSL
public key encryption tec in HTTP - 164security transactionssecure socket layer SSL:
public key encryption tec in HTTP
security token:
send SMS to user the time-sychronized one-time password
mobile short message service SMS
Smart card:
store information about card holder for identity authentication - 165hacker vs crackercracker for illegal activities for hacking
- 166who are responsible for data privacydata privacy are protected by Personnal Data Ordinance PDO in office Privacy Commissioner for Personal Data PCPD
- 167what PDO let users know and dokind of personal data
purpose of keeping
able to access and amend collected data - 168phishing (what, suffer, measures)What: email from fake website to trick confidential data
social engineering
Suffer: financial loss, denial of access
Measures: dont open suspicious hyperlinks or URL
alert when confidential data requested
Informationen
- Beschreibung
- Form 5 Computer and Information Technology Karteikarten am ICT, erstellt von YoGurd NoLife am 16/06/2018.
- Erstellt von
- YoGurd NoLife
- Aufrufe
- 8
- Bewertung