 Hello everyone, welcome to the session on file transfer protocol. Learning outcome, at the end of the session students will be able to describe the concept of file transfer protocol content, connection, communication, file types, data structure, transmission modes and then command processing. These are the topics I am going to cover in this video. Let us in detail one by one about file transfer protocol. File transfer protocol is an update protocol. It can be used for transmitting the file from one user to another user or exchanging the data between two users. Here FTP uses a service of TCP that is a transmission control protocol. It needs two types of TCP connections that are control connection and data connection. These two types of connection can use the two different port number that are well-known port number 20 is used for the control connection and well-known port number 20 is used for the data connection. This is a block diagram of file transfer protocol. It can contain different components in the sender side as well as the issuer side. At the sender side, three components are there that are user interface, control process and data transfer process. The issuer side also control process and data transfer process. Two components are there. The file transmitting the data between one user to another user. We have to use two types of connection that is control connection and data connection. Control connection is remains open until whole communication will be complete. Data connection can each and every time it can open the connection and closes the connection in the communication. FTP connection or two FTP connections are control and data. I use the different strategies and different port numbers. Okay. Control connection. The connection remains open during the process. Here we have to use three steps that are the server issues of pass you open on a well-known port number 21 and waits for the client. After opening, the client uses a ephemeral port number and issues a active open. This is the block diagram of control connection here. Two diagrams are their control process, client side, control process in the issuer side. It can open the pass you open using port number 21. Okay. First and pass you open by the server. Next one is later active open by the client. Here active open is there in the client side. The control process in the client side can use the active open using a ephemeral port number that is the issuer side also already opened here that is by using pass you open. Port number 21. Next one is data connection. Here it uses the data connection uses a well-known port number 20 at the server side. The following shows the how FTP opens the connection. Okay. FTP opens a connection in in the client side data transfer process. It can opens a pass you open port number ephemeral port number in the data transfer process in the server side. First pass you open by the client and then they can send ephemeral port number through control connection to the issuer side. That is sending. Second is sending of ephemeral port number. Third one is active open by the server. And then after sending, it can opens active open by using the ephemeral port number 20. And then they can opens the connection. Data connection uses a well-known port number 20 at the server side. The creation of the data connection is different from the what we have discussed in the previous PPT. Here three steps we have to use that are the client not the server. It shows a pass you open using well-known port number ephemeral port number. This must be done by the client. The client sends this port number to the server using the port command that is this the PORT command. And then after sending that the server resues the port number and issuer and active open using the well-known port number 20. And resued ephemeral port number in the issuer side. Next thing can write it can contains one question that is what is FTP and list some difference between FTP and SFTP. FTP is in file transfer protocol and SFTP is in secure file transfer protocol. Now pass the video and answer the above question. Answer for the above question definition FTP that is file transfer protocol is a client server protocol used for transferring the file to or from or exchanging the file the computer host. Generally FTP can be used for transmitting or sending or exchanging the data between two hosts or computers. The difference between FTP and SFTP is in serial number. There are six difference are there that are first one is FTP stands for file transfer protocol and SFTP stands for secure file transfer protocol. In FTP secure channel is not provided to transfer the files between the host. In SFTP secure channel is provided to transfer the files between the host. FTP use FTP is a part of TCP IP protocol SFTP is a SHH protocol that is secure cell protocol. FTP usually runs on a port number 21 SFTP runs usually runs on a port number 22. FTP establish the connection under TCP protocol SFTP establish the control connection under SHH protocol. FTP do not encrypt the data before sending. In general it can prepare and then it can send the data. SFTP before transmitting any data it can encrypt it and then it can send it to the receiver as the name itself indicates SFTP that is secure file transfer protocol. If you are sending the data through secure file transfer we won't face any problem in the data transfer process. Next one is FTP communication. Two computers may use a different operating system different character set different file structures and different file formats also. Then how we how to by using FTP we how to manage that type of problems. Here two different approaches one for the control connection and one more for the data connection. First one is a FTP communication communication or control connection. It uses NVT that is a network virtual terminal ASCII that is American standard coded information interaction characters communication is achieved through commands and responses. Here local operating system it can prepare the data and then through local code can send it to the control process in the client side and through NVT ASCII they can transfer it to the server side the server can show the data and then it can perform the data and then it can send it to the remote operating system it means server side operating system using the control connection. Communication over data connection the purpose and implementation of the data connection are different from the from that of the control connection here. The client must define type of file to be transferred. Structure of the file and the structure of the data and transmission mode. Here in generally the local file the user can get the data from the local file in the data transfer process and then it can prepare what type of file they are sending what is a structure or data structure and then transmission mode are defined by the client. Before transmitting they have to define the type file type data structure and transmission mode after preparing all those things then they can send the data through the data connection in the receiver side the receiver side processor they can issue the data and then perform it and then send it to the remote file system they can issued in the receiver side. File type FTP can transfer one of the following file type across the data connection ASCII file that is American Standard Coded Information Interchange File. This is the default format for transferring text file each character is encoded using NVT ASCII that is Network Virtual Terminal American Standard Coded Information Interchange. And this file by using this one also we have to transfer the data next one is EBCDIC file if one or both ends of the connection uses EBCDIC encoding the file can be transferred using EBCDIC encoding what is the full form of this one is encoded binary coded decimal information interchange code it can be used for transmitting the data in the receiver side from one user to the another user. Image file this is the default format for transferring the binary files to the user such as compiled programs data structure FTP can transfer a file across the data connection using one of the following interpretations about the structure of the data file structure it is our default structure the file has no structure it is a continuous stream of bytes record structure this file is divided into records this can be used by used only with the text files they can prepare and then they can send the data page structure this the file is divided into pages first how many number of pages are there in that file with each page having a page number and page header the file can be stored and accessed randomly or sequentially it means before transmitting any data the user the page structure can contains page number header information and then after preparing that we have to put that data in a file that file we have to transfer to the next user this is the types of the page structure by using this one we have to transfer the data these are the references I have used for preparing the above ppt thank you