tailieunhanh - Network+ Certification (Outline) - Chapter 10: TCP/IP applications

Chapter summary: Bridges selectively relay packets between network segments, depending on their data-link layer destination addresses; bridges maintain a single broadcast domain and create separate collision domains; switches improve on the function of bridges by forwarding packets only to their destination systems;.and other contents. | Chapter 10 TCP IP Applications 1 Chapter Overview A. TCP IP Services B. TCP IP Utilities Chapter 10 Lesson 1 TCP IP Services 1. DHCP A. DHCP origins 1. 2. 2 3. TCP IP configuration is a complex issue because every computer must have a unique IP address. You must keep track of the assigned IP addresses to ensure that no duplication occurs. There have been several automated TCP IP configuration solutions over the years including a. b. Reverse Address Resolution Protocol RARP Bootstrap Protocol BOOTP DHCP 3 4. 4 5 5. c. RARP Uses the same message format as Address Resolution Protocol ARP Essentially the opposite of ARP Designed for diskless workstations with no means of storing Internet Protocol IP addresses Not suitable for today s networks because it supplies only an IP address no other TCP IP configuration parameters No longer used An RARP client broadcasts its hardware address to an RARP server and receives an IP address in return. BOOTP Still used occasionally Can furnish a client with an IP address plus all of the other required TCP IP configuration parameters including IP address subnet mask default gateway and DNS server addresses A diskless workstation can also download an executable boot file from a BOOTP server by using the Trivial File Transfer Protocol TFTP . Disadvantages 1 a. b. c. d. e. f. a. b. c. d. 2 3 You must configure the server with the IP address and all other configuration parameters for each client. No mechanism to automatically assign an IP address to a client No mechanism to prevent IP address duplication due to administrator error 6 6. DHCP a. Addresses the shortcomings of RARP and BOOTP b. Dynamically allocates IP addresses from a pool called a scope c. Reclaims unused addresses d. Prevents duplicate address assignments e. Supplies all TCP IP configuration parameters B. DHCP standards 1. Based on public BOOTP standards 2. Defined in Request for Comments RFC 2131 and RFC 2132 3. Published as an open TCP IP standard C. DHCP architecture 7 .