psychological effects of stress to pre engineering students
DATA
COMMUNICATIONS
10-1
Communication Basics
Computer communications is at three levels
– Application level
– Computer level
– Communication channel
Protocol
– Set of rules for communications
– OSI Standard
10-2
OSI Reference Model
Layer
7
6
5
4
3
2
1
Name
Application Layer
Presentation Layer
Session Layer
Transport Layer
Network Layer
Data Link Layer
Physical Layer
Purpose
Application-to-application communication
Manage data representation conversions
Establish and maintain communication channel
Guarantee end-to-end integrity of transmission
Route data between network addresses
Move data from one network address to another
Put data onto and off of the network media
10-3
ISO Website
10-4
Protocols for Computer
Communication
Early computers
– Terminals
– Sneaker net
System Network Architecture (SNA)
– Established by IBM in 1974
– Proprietary
Token-Ring
– Host computer controlled
– peer-to-peer
10-5
Protocols for Computer
Communication
Ethernet
– Xerox working with Intel and Digital
Equipment Corporation developed this protocol
– Non-proprietary
– Defined by IEEE
– Works on a single transmission line
– No token is passed
10-6
Packets
Piece of the total data to be communicated, combined with the address of the destination computer for the data and other control information. Transmission Control Protocol/Internet
Protocol (TCP/IP) is one of the more important packet switching protocols
10-7
Network Addresses
Address
– Four-part set of numbers
– Each from 0 to 255
Internet Service Providers (ISPs)
– User connects through common carrier
Serial Line Internet Protocol (SLIP) and
Point-to-Point Protocol (PPP)
– Protocols for users at home
10-8
Protocols for Public Phone
Systems
X.25
– analog
– older protocol
Integrated Services Digital Network (ISDN)
– Digital
– Can carry
COMMUNICATIONS
10-1
Communication Basics
Computer communications is at three levels
– Application level
– Computer level
– Communication channel
Protocol
– Set of rules for communications
– OSI Standard
10-2
OSI Reference Model
Layer
7
6
5
4
3
2
1
Name
Application Layer
Presentation Layer
Session Layer
Transport Layer
Network Layer
Data Link Layer
Physical Layer
Purpose
Application-to-application communication
Manage data representation conversions
Establish and maintain communication channel
Guarantee end-to-end integrity of transmission
Route data between network addresses
Move data from one network address to another
Put data onto and off of the network media
10-3
ISO Website
10-4
Protocols for Computer
Communication
Early computers
– Terminals
– Sneaker net
System Network Architecture (SNA)
– Established by IBM in 1974
– Proprietary
Token-Ring
– Host computer controlled
– peer-to-peer
10-5
Protocols for Computer
Communication
Ethernet
– Xerox working with Intel and Digital
Equipment Corporation developed this protocol
– Non-proprietary
– Defined by IEEE
– Works on a single transmission line
– No token is passed
10-6
Packets
Piece of the total data to be communicated, combined with the address of the destination computer for the data and other control information. Transmission Control Protocol/Internet
Protocol (TCP/IP) is one of the more important packet switching protocols
10-7
Network Addresses
Address
– Four-part set of numbers
– Each from 0 to 255
Internet Service Providers (ISPs)
– User connects through common carrier
Serial Line Internet Protocol (SLIP) and
Point-to-Point Protocol (PPP)
– Protocols for users at home
10-8
Protocols for Public Phone
Systems
X.25
– analog
– older protocol
Integrated Services Digital Network (ISDN)
– Digital
– Can carry