Data Communication enables communication within the devices. Different methods have been used and associated with each method are various advantages and disadvantages.
Communication mainly based on concept of layers in our daily life.
For example consider two friends who communicate through postal mail and the steps related to it are
Sender
Step1: The letter is written,put in an envelop,and dropped in a mailboxHigher layer.
Step2: The letter is carried from the mailbox to a post office-Middle layer.
Step3: The letter is delivered to a carrier by the post office-Lower layer.
Reciever
Step1: The letter is picked up,removed from the envelope and read-Higher layer.
Step2: The letter is carried from the post office to the mailbox-Middle layer.
Step3: The letter is delivered from the carrier to the post office-Lower layer.
By using the technology we can implement the above communication in devices using OSI (Open System InterConnection) MODEL
It was first introduced in the year late 1970s.
An open system is a set of rules that allow any two different systems to communicate
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N.Anjaneyulu
Asst.Professor
CSE Department
Sphoorthy Engineering College
Communication mainly based on concept of layers in our daily life.
For example consider two friends who communicate through postal mail and the steps related to it are
Sender
Step1: The letter is written,put in an envelop,and dropped in a mailboxHigher layer.
Step2: The letter is carried from the mailbox to a post office-Middle layer.
Step3: The letter is delivered to a carrier by the post office-Lower layer.
Reciever
Step1: The letter is picked up,removed from the envelope and read-Higher layer.
Step2: The letter is carried from the post office to the mailbox-Middle layer.
Step3: The letter is delivered from the carrier to the post office-Lower layer.
By using the technology we can implement the above communication in devices using OSI (Open System InterConnection) MODEL
It was first introduced in the year late 1970s.
An open system is a set of rules that allow any two different systems to communicate
The Physical Layer:
The Physical layer deals with the signals. Signals are defined by 0 and 1. It also deals with the networks and interlinks with the data link layer.
The Data Link Layer:
The Data Link layer deals with the functionalities like
a. Error Control
b. Flow Control
c. Access Control
It also deals with the sub layers like
LLC-Logic Link Layer and MAC-Medium Access Control
The Network Layer:
The Network Layer is responsible for Packet Forwarding.
It deals with addressing protocols like IPV4 and IPV6.It also deals with the ICMP,ICMPV6 and IGMP protocols.
The Transport Layer:
The Transport Layer responsible for accepting data from above and it also provides the types of connection.
Transport layer supports two protocols
1. TCP-Transmission Control Protocol(Connection Oriented).
2. UDP-User Datagram Protocol(Connectionless).
The Session Layer:
The Session layer supports Tokenization and Synchronization.
It is sometimes called as the Port layer.it is the value added layer.
The Presentation Layer:
The presentation layer deals with the syntax and semantics.
It mainly supports encryption and also Compression.
The Application Layer:
The application layer supports high level protocols like HTTP, SMTP and FTP. This layer is used for reading and writing data.
The above layers related to Traditional model as 3 subgroups:
Higher layer-these are user support layers named as Session, Presentation and Application Layer.
Middle layer-Links the higher and lower layers named as Transport Layer.
Lower layer-these are Network Support Layers named as Physical, Data link and Network Layer.
N.Anjaneyulu
Asst.Professor
CSE Department
Sphoorthy Engineering College
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| Sphoorthy Engineering College |
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