1. [10 points] Define the following terms using your own words and complete sentences:Source Quench:In Internet Control Message Protocol (ICMP) is a source quench message from one destination (Host) computer to a source computer telling it to slow down the rate at which packet is been send. The sources quench help to manage and control flow of packets on the internet so that no packet is lost in the process of stacking.De Jure Standard:De Jure Standard is hardware or software that is endorsed by a standards organization. De Jure Standards are standards that have been accepted by standard bodies of specialized organizations and government body.IRTF:The basic work of the internet Research Task Force is to do a research on the issues related to internet protocols, applications, architecture and technology. This mean they are expected for a long term and promote the development of research and teamwork exploring issues related to internet. The Internet Research Task Force (IRTF) is a sister group to the Internet Engineering Task Force (IETF).DF bit in IP header:DF meaning dont defragment is a bit set within IP header that determines when a packet fragment should be defragmented by a router or not. It is a failed on the header set to 1 when applications do not what to fragment the packet because it is not useful when node fragment the packet.ARP Cache:The Address Resolution Protocol (ARP) cache is a table contains the IP addresses and the MAC addresses for the computers in the same network. The Network Layer contains the Internet Protocol (IP) addresses, while the Data Link Layer contains the Media Access Control (MAC) addresses. The IP addresses corresponded to the MAC addresses when the computer wants to send a packet to another computer in same network. It provides fast look up and reduce the traffic for obtaining the MAC address when every time the computer wants to send a packet. Each system employing the ARP protocol uses this cache of recent mappings to minimize the number of ARP requests. The Operating System stores the cache in Random Access Memory (RAM).2. [10 points] Briefly explain how ICMP and IP work together.ICMP integrated to IP protocol, it is part of IP address. IP address is not reliable protocol, so when the packet lost there is no guaranty to deliver the packet. The purpose of these control messages is to provide feedback about problems in the communication environment, not to make IP reliable. There are still no guarantees that a datagram will be delivered or a control message will be returned. Some datagram may still be undelivered without any report of their loss. The higher level protocols that use IP must implement their own reliability procedures if reliable communication is required. The ICMP provides communication between the Internet Protocol software on one machine and the Internet protocol on another machine. IP implementations are required to support this protocol. ICMP provides error reporting, flow control and first-hop gateway redirection.