Computer Networks. Part Six: The TCP/IP Protocol Stack and Routers

This is the sixth in a series about computer networks. This video describes the role of a network protocol, and specifically details the TCP/IP suite of protocols. The need for a layered approach to networking software is discussed including the four layer TCP/IP stack and the relevance of protocols such as HTTP, FTP, SMTP, POP, IMAP, VOIP, TCP, IP, UDP, ICMP and ARP. Transmissions Control Protocol (TCP) and Internet Protocol (IP) are described in greater detail, along with the need to configure an IP address, subnet mask and default gateway on a networked computer. IPv4 and IPv6 addresses are compared, and the use of Dynamic Host Configuration Protocol (DHCP) and proxy servers gets a mention. The structure of an IP packet is illustrated, as is the nature of a packet switched network consisting of several interconnected routers and switches. The way in which the MAC address of an Ethernet frame is changed each time a packet hops from one router to the next is also illustrated, along with the role of the address resolution protocol, ARP. .