Programming & Networking (MERN + Cisco + Microsoft)

Repeater  hello friends i am Vasu Birla and today i am starting new segment of CCNA computer networking  its a Networking Devices. we will discuss every important Devices used in networks. Repeater is a first networking devices. What is Repeater  Repeater is a device that receives signals and re-transmits by amplifying or regenerating signals. Repeater has two port one is for receive signals from previous network and second port is for retransmit signals to the next extended network. Two Port Repeater Repeater is a device which is used to Regenerate or replicate signal (Pichhe se aa rahe signal ko regenerate karke ya amplify karke aage strong signals bhej sakte he) Analog and digital both type of signals can be retransmitted by repeater. Here there is difference between regeneration and amplifying.  Amplification means , received signals will be amplified as it is , whether there are impurities in signals  and Regeneration means repeater will remove impuritie

Application Layer  It is nearest layer to use, It woks as a interface between actual application and remaining all layers.  application layer provides services to software applications and programs it means. Apllication Layer functions  Identifying communication partners (It means application layer identify the partner who is to be communicate on network) Determining resource availability (Check the network recourse availability like modem, switch, router ets.) Synchronizing Communication (This layer ensure that communication is being done in synchronize way )  

Presentation Layer  Hello friends , i am vasu birla and today will talk about 6th layer of OSI model. Note this these layers are not software or hardware, it is just for understanding and logical theory of understanding of working of network. We can understand this layer by it's name Presentation  means to present something. When any system sends data to another system so it may be that second system would not present the same data as given by sender system. Presentation layer make data viewable according to recieving system.   For more easy understanding lets look some functions of this layer- Translation -  There are different kind of platforms in the network (windows, linux, mac etc) these systems are different so way of presentation of  data is also different. for this problem presentation layer Translate the data from original form to viewable form of recieving system. for example if you open any website on Windows OS  like www.vasubirla.blogspot.

Session Layer  OSI Model's fifth layer is session  layer. This layer handles the issues which are related to software.  Session layer maintain session from the user connected to terminate connection. (User ke internet se connect hone se lekar disconnect hone ke bich ke sare session establish and terminate karne ka kaam session layer karti he)some important functions are performed by this layer are follows; Establishing connection. Maintaining connections Synchronizing communication Controlling dialogues Terminating connections. Session Layer is responsible for establishing , maintaining and terminating sessions between the end level users. These sessions are made by  request and responses among applications. For example-  When we use web browser and logon to different websites so at that time many sessions are created for each websites.  for more easy understanding  suppose at a time i am downloading any file so at that time i would being used FTP proto

Transport Layer  hello friends , i am Vasu Birla and today we will dicuss about he forth layer that is Transport Layer.  This layer works as a transaction point between upper three layer application , presentation , sessikon layers and lower three data layers   physical , data link and network layer. As we all know today’s computers supports multitasking features.   Multitasking means at the same thime multiple applications can be run and send and recieve data . Transport layer provides servieces through which these all applications can send and receive data using lower layers at the same time.  Transport layer is also responsible for end to end transport. Transport layer moniters diffrent kind of data which recived from diffrent application. Transport layer combines these data into a single data unit and send it to lower layer. And at lower layers recieving devices split this single unit data and send to compatible applications. (Jo data transport layer s