 Hello everyone. Myself, Mr. Seopai M. Matagar, I am working as a student professor in Computer Science and Engineering Department at Walton Institute of Technology, Solopor. In this lecture, I am going to explain about host configuration. Now, let us see the learning outcome of this host configuration lecture. At the end of the session, the students will be able to explain the concept of boot P protocol. Second one is, students will be able to explain the concept of DHCP protocol. In this lecture, I am going to explain about boot P protocol, about DHCP, DHCP protocol, DHCP operations. Now, let us see one by one in detail. First one is about boot P protocol. Boot P is a bootstrap protocol, is an internet protocol that can provide network configuration information to diskless workstation. Diskless workstations need to obtain a boot image from a disk on the network because they do not have their own disk from which to obtain this information. The boot P image provides all files, all the files required to start the operating system on the computer. After booting the system for the first time, if the user want to add some softwares in that, that time they can use a boot P protocol. In that time, they can use the RARP protocol, that is reverse address resolution protocol to obtain an IP address only boot P obtain an IP address, gateway address and then name server address. Boot P was designed for manual pre-configuration of the host information in a server database. Boot P is also used to initialize IP addresses. About boot P information, after booting the system for the first time, if the user want to add or configure that booted system, that time they can use boot P protocol for configuring the system. For that purpose, they have to use four piece of information that are the client IP address, subnet mask, default gateway addresses, the IP address and host name host name of the boot P protocol, the IP address of the server that has the boot image, which the client need to load its operating system. After loading all the information, the system can get configured and it can operate as usual by using operating system. Next one is about DHCP. DHCP is a dynamic host configuration protocol. It is a network management protocol used to dynamically assign an IP address, IP address to any devices or nodes or on a network. So they can communicate using IP. DHCP automates and centrally manages these configurations rather than requiring network administrators to manually assign IP address to all network devices. DHCP can be implemented on a small local networks as well as large enterprises. If the user want to assign some other data, they how to use internet, in that internet they won't use DHCP for configuring the system. If they have used boot P, then they can, boot P isn't static, then DHCP they can dynamic by using this DHCP, they can configure the system manually. Next, think and write. This think and write can contains two questions that are, what is the purpose of DHCP, second one is, what are the three mechanisms supported by DHCP for IP addresses, IP address allocation. Now pause the video and answer the question. Now let you see the answer for first question. DHCP server host allocates network addresses to the clients and deliver configuration parameters to the dynamically configured host. So answer for second one is, second one is three mechanisms that are automatic allocation, dynamic allocation, manual allocation. Now DHCP operations. There are five different operations are there that are same network, different network, UDP ports, using TFTP, error control. First one is same network. If both client and server, they want to send the data and issue the data, then that time they can use a DHCP protocol. If both client and server are there in a same network, then that time we have what are the different concepts we have to follow. This diagram can contains same network. Here both DHCP client as a DHCP server are there in a single line. Here we have to use some shortcuts that are CP, SP, CIP, SIP. CP is a client port number, server port number. CIP is a client IP address, SIP is server IP address. Here in the DHCP client, they can use some port numbers to configure the packet. Here in a client side, they can use the server side. They can use a port number 67 and then in the client side, they can use the port number 68 for fixing the packet. Here this is a simple packet. The port number 67 is in server IP address. 68 is in client IP address. 1 and 1s and 0s are the information related to the data. If while sending the request, the client should have to put 1s and 0s. 1 is in server IP address and then 0 is in client IP address. After putting this information, the client can, after configuring this packet, the client can send this packet to the server side. After sending this packet to the server side, then server can issue the information. Then they can analyze the data. Then again it can reconfigure the receiver side packet. This packet can contain the DHCP reply. Then port number 68, the CP is in client port number. 67 is in server port number. Once here, this packet can contains only 1 because it is a reply message. SIP is in server IP address. Then after configuring this packet, the client server can reply based on the client packet request message. Then after that both client and server, they can send the data and issue the data in a same network. If they are there in different network, then they can go to the next operation. Here, there is no need to go for. Yes, if the both client and server are there in a single network, they can send the data and issue the data. If something is happened, then they can easily access the data and packets where exactly the error is happened. They can easily find out that in a same network. Next one is different network. Here, both client and server are there in different networks. Here, client is there in one network. After preparing that packet, they have to send the data through internet to another network. The server is there in another line. The client is there in one line. Here, if both client and server are there in a different line, then the client will send the unicast message. Then the server won't issue or through internet, it is not possible to send the unicast. For that here, for that purpose, here we have to use Relay Agent. Relay Agent, why we have to use this Relay Agent? What is the role of this Relay Agent? The Relay Agent can converts a broadcast request to the unicast request, unicast request to the broadcast. Here, the DHCP client can prefer or configure the packet. After configuring, they can send that packet to the Relay Agent. The Relay Agent can check the IP address or whether it is in broadcast or unicast. If it is broadcast, it can converts it into the unicast. Then after converting, it can send through router to the internet. In the internet, the internet can check the information. Then again it can refoward to the router, through router to the DHCP server side. The DHCP server side, again they can check the data. Then if it is matched, then only it can accept the data. If it doesn't match, then it can discuss. Here, the main thing, what is the difference between same network and different network? It means here they have used, both client and server are there in a single network. It means it is same network. Both client and server are there in different network. It is a different network concept. Here, we have to use Relay Agent. One of the important role for Relay Agent is conversion. After that, it can send the data and reshoot the data by using this concept. Use of UDP ports. Here, this DHCP protocol can use DHCP protocol. In the server side, they can open the passive open by using 67 port number. In the client side, they can open the active. By using these port numbers and then they can use the UDP protocol. By using UDP protocol and then 67 and 68 is in well-known port numbers. By using those port numbers, the both client and server, they can exchange the data. By using 68, it can send the request. After receiving the request at the receiver side, the receiver can reply based on the client request using port number 68. DHCP operations. These are these two more operations of DHCP. Fourth one is using TFTP. TFTP is Trivial File Transfer Protocol. The server does not send all of the information that the client may need for voting. The server can define the path name of the file in which the client can find complete voting information. Error control. DHCP requires that UDP uses the checksum. Remember that the use of checksum in UDP is optional. DHCP client uses timers and retransmission policy if it does not receive the retransmission. Checksum is a part we have to use for finding the errors in a packet. These are the references I have used for preparing the above PPT. Thank you.