3 Networks Flashcards
Repeater
Regen signals when you need to exceed cable length allowed by physical layer standard
Redistribute signal from open cable to another
Do not amplify signal
Hub
Regen every signal received on any port
on all hubs other ports
Multi port repeated
Bridge
Repeater
Filter content by reading MAC address of src dest.
Interconnect 2 LANs working on same protocol
2 port input output
Switch
Multi port bridge
Error check b4 forward data
Efficient
Router
Like switch Route data based on IP Connect LAN WAN Determine efficient route Cable/wireless
Circuit switching
Def
Adv
Disadv
packet path decided before comm, one route all packets
Voice
Packets delivered same order
Less delay b4 and during call
If goal: clear, reliable, voice comm channel
.
Not ideal data transmission
Data sent receive in streams
Line remain idle in between transmission spurts
Waste of badndwidth
Slower (attach hosts b4 data exchange)
Dedicated channel unavailable for any other use
Higher cost dedicated one channel per use
Packet switching
Def adv
Disadv
each pack takes on route, routed between nodes, on internet rooted by router
Efficient : find own data path to destination address without need for dedicated channel
For not time sensitive
No lost data packets (resending)
Cost effective
Utilize bandwidth
If goal: facilitate multiple voice and data applications same time
.
No for constant use:call
Network can lose data packets in high traffic times(cannot recover/resend)
Lack security protocols during transmission
Message switching
transmit whole set of data tgt w.out predefined route Data sent to node, temp store Later forward to node Aka store and forward Slow, avoid traffic No real Time Email if change server
Infrared
Infrared: low bandwidth, sunlight, line of sight, cheap, tv remote, wireless Ouse, keyboard
Fiber optics
Adv
Disadv
0 interfere Cover major cities and countries Secure Speed Cant be tapped Distance> twisted pair
Install maintain an
Cabling $
Icopamtable w types of networking equipment
Laser
cover larger distance,
line of sight,
used to connect to LAN.
Secure
Wireless
less frequencies avail less bandwidth, copper , interference, expand w/out disturbing current users , security issues, limited speed
Optical
Bandwidth>copper Voice data video Light waves Most secure Installation maintenance difficult , costly
Copper wire
Long cable Prone to noise > unreadable
Cheap ez low resistance to electrical current
Conductive use alongside machinery need reliable electrical connection
Flexible w set up less insulation armouring
High melting point
Longevity
Malleable
LAN protocol
WLAN
data deliver efficient short distance Copper cable Ethernet Home / office CAT5 copper cable Switch / hub
WLAN
Wireless signal betel antenna rather than cable
WAN protocol
data deliver efficient long distance
ISDN
Ppp
MAC address
physical address ID of divorce Data link layer Actual hardware address Assigned to device at factory Network interface card address burne inside when made
HTTP
Browser (client) initiate connect to server (needed IP)
Send request to server
Server receive request from client
Respond w appropriate data
SMPT send email from client to server/ server to server
IMPA/POP client receive email stored in server
POP: mail client get mail from server, no keep copy, Downalod message on client computer and delete from server part of application layer.
IMAP: can read/retrace from server, want be deleted unless requested Support multiple folders unlike POP. Part of application.
FTP
added security
Transfer Minaj files
Operation stuffs (upload download delete rename operations)
File stored in FTP server
File access : authentication
HTTP more used in file sharing (cloud )
FTP better w large files , business, uncommon
TCP vs UDP
TCP connection oriented Slower Packet move over network Reliable without error Retransmission lost data packets UDP connectionless Faster Simpler Efficient
VM vs dedicated server
VM - Cheaper - A crash will not affect other VM in the shared resource environment - Data alr backed up , ok if it crashes
Dedicated
- Run smoother
- Better performance and security; do not need to distribute resources among different users
- Larger capacity
- If crash, whole system reconfiguration
Sending email
SMPT
John is sending an email from CTM email to Mary who is using hotmail. (Client application, server, protocols involved in the process)
- smpt server processes your email
- Decides which server to send the message to
- Relays the message to the server -
- POP3 Post office protocol
- One way
- Client server
- Email is received and held on the email server -
John composes his email
- Send the email from his client machine to CTM
email server (located in internet)
- SMTP server then communicates with a DNS
(domain name server)
- To find corresponding IP Address for the domain
being sent to
- Once IP address resolved
- SMPT server connects with hotmail server - Mail is delivered to this server for handling
Satellite basic
Satellites in space send microwaves down to earth
Low earth orbit : 40-80
Medium : 8-20
Geostationary : 3
No: areas no wireless/wired broadband connection
