komunikasi data

1. Internet Network, Protocols
and Standards
References : William Stallings, Behrouz Forouzan
Pradini Puspitaningayu

2. Have you find the books?
William Stallings, Data and Computer Communication
Behrouz Forouzan, Data Communication and Networking

3. Wide Area Networks (WAN)
• Large geographical area
• Crossing public right-of-ways
• Rely at least in part on circuit provided by a common
carrier
• Consisit of a number of interconnected switching
nodes
• Alternate technologies :
– Circuit Switching
– Packet Switching
– Frame Relay
– ATM

4. Circuit Switching
• A dedicated communications path is established
between two stations through the nodes of the
network
• Data generated by the source station are transmitted
along the dedicated path as rapidly as possible
• At each node, incoming data are routed or switched
to the appropriate outgoing channel without delay
• Example : telephone network

5. Packet Switching
• Data are sent out in a sequence of small chunks,
called packets
• Each packet is passed through the network from
node to node along some path leading from source
to destination
• At each node, the entire packet is received, stored
briefly, and then transmitted to the next node
• Example : terminal-to-computer and computer-to-computer
communications

6. Frame Relay
• Packet switching systems have large overheads to
compensate for errors
• Modern systems are more reliable
• Errors can be caught in end system
• Most overhead for error control is stripped out
• Packet Switching vs Frame Relay
– Packet switching’s data rate about 64 kbps
– Frame relay’s data rate up to 2 Mbps

7. Asynchronous Transfer Mode
• ATM
• Developments in circuit switching and packet
switching
• Evolution of frame relay
• Little overhead for error control
• Fixed packet (called cell) length
• Anything from 10Mbps to Gbps
• Constant data rate using packet switching technique

8. Integrated Service Digital
Network (ISDN)
• Designed to replace public telecom system
• Wide variety of services
• Entirely digital domain

9. Local Area Network (LAN)
• Smaller scope
– Building or small campus
• Usually owned by same organization as
attached devices
• Data rates much higher
• Usually broadcast systems
• Now some switched systems and ATM are
being introduced

10. Protocols
• Used for communications between entities in a
system
• Must speak the same language
• Entities
– User applications
– e-mail facilities
– terminals
• Systems
– Computer
– Terminal
– Remote sensor

11. Key Elements of Protocols
• Syntax
– Data formats
– Signal levels
• Semantics
– Control information
– Error handling
• Timing
– Speed matching
– Sequencing

12. Protocols Architecture
• Task of communication broken up into
modules
• For example file transfer could use three
modules
– File transfer application
– Communication service module
– Network access module

13. Simplified File Transfer
Architecture

14. Protocol Architecture & Network

15. Protocol Data Unit (PDU)
• At each layer, protocols are used to communicate
• Control information is added to user data at each
layer
• Transport layer may fragment user data
• Each fragment has a transport header added
– Destination SAP
– Sequence number
– Error detection code
• This gives a transport protocol data unit

16. Operation of a Protocol
Architecture

17. Standards
• What is standards?
– A standards provides a model for development
that makes it possible for a product to work
regardless of the individual manufacturer
• Why we need standardization?
– Creating competitive market
– International interoperability and interconectivity
– Simplification

18. Non-standard VS Standard
K sources and L receivers leads to K*L protocols and 2*K*L implementations.
If common protocol used, K + L implementations needed

19. Standard Organization
• International Standards Organization (ISO)
• International Telecommunication Union –
Telecommunication Standards Sector (ITU-T)
• American National Standards Institute (ANSI)
• Institute of Electrical and Electronics
Engineering (IEEE)
• Electronics Industries Association (EIA)
• Telecordia

20. Task
• Find out what standards have been made by
ISO, ITU-T, ANSI, IEEE, EIA, Telecordia
• Translate William Stalling’s Data and
Computer Communication
– Page 25-53
– Format MS Word, Include the graphics
– Deadline : Thursday 25/09/2014 11:00 AM
Quiz 29/09/2014