Chapter 13 Flashcards
Internet backbone
a collection of large national and international networks (most of which are owned by commercial, educational, or govn’t organizations)
IXP
made up of one or more internet switches to which internet service providers connect to
T line
carried digital data over twisted pair lines.
backbone ISP initially connect with T lines.
Point of presence (POP)
individual users enter a ISP through a POP.
- usually a modem, switch, routers, etc.
client/server model
clients: devices such as computers, tablets, and smartphones that use browsers to request services such as web pages
servers: web servers, commerce servers, file servers
web server
computers that run specialized OS enabling them to host web pages and to provide requested info to clients
commerce servers
computers that host software that enables buyers to buy goods and services over the web
file servers
computers that are deployed to provide remote storage space or to act as storehouses for files that users can download
computer protocol
the set of rules for exchanging electronic info
why was protocols invented?
anyone can use their computer system and be able to communicate with any other computer using the same protocol
open system
it’s design would be made public for access by any interested party
- each protocol has to be open system
opposite of open system?
poprietory system
proprietary system
private system
circuit switching
a dedicated connection is formed between two points and the connection remains active for the duration of the transmission
why is circuit switching important?
when communications must be received in order they were sent (phone conversation)
what device is circuit switching usually used for?
a phone, never computers
if computers don’t use circuit switching then what do they use?
packet switching
packet switching
data is broken into smaller chunks (data packets) and are sent over various routes at the same time. when the packets reach their destination they’re reassembled by the receiving computer.
what info does a packet contain?
- an address the packet is being sent to
- the address the packet comes from
- reassembly instructions if the data is split up
- the data that is being transmitted
internet protocol (IP)
sends data between computers on the internet
transmission control protocol (TCP)
prepares data from transmission and provides for error checking and resending lost info
user datagram protocol (UDP)
prepares data for transmission: lacks resending ability
file transfer protocol(FTP)
enables fies to be downloaded to a computer or uploaded to other computers
telnet
enables user to log in to a remote computer and work on it as if sitting in front of it
simple mail transfer protocol(SMTP)
used for transmission of email messages across the internet
DHCP
takes a pool of IP addresses and shares them with host on a network on as needed basis
dynamic host configuration protocol(DHCP)
takes a pool of IP addresses and shares them with host on a network on as needed basis
Real-time transport protocol (RTP)
network protocol for delivering audio and video over IP