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.
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Network+ Certification (Outline) - Chapter 10: TCP/IP applications 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. TCP/IP configuration is a complex issue because every computer must have a unique IP address. 2. You must keep track of the assigned IP addresses to ensure that no duplication occurs.|2| 3. There have been several automated TCP/IP configuration solutions over the years, including a. Reverse Address Resolution Protocol (RARP) b. Bootstrap Protocol (BOOTP) c. DHCP|3| 4. RARP a. Uses the same message format as Address Resolution Protocol (ARP) b. Essentially the opposite of ARP c. Designed for diskless workstations with no means of storing Internet Protocol (IP) addresses d. Not suitable for today’s networks because it supplies only an IP address, no other TCP/IP configuration parameters e. No longer used|4| f. An RARP client broadcasts its hardware address to an RARP server and receives an IP address in return.|5| 5. BOOTP a. Still used occasionally b. 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 c. A diskless workstation can also download an executable boot file from a BOOTP server by using the Trivial File Transfer Protocol (TFTP). d. Disadvantages: (1) You must configure the server with the IP address and all other configuration parameters for each client. (2) No mechanism to automatically assign an IP address to a client (3) 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| 1. Has three components: client, server, and protocol 2. DHCP client a. Integrated into the TCP/IP implementation in most operating systems (1) Usually integrated into the networking client, even if the operating system does not explicitly call it DHCP b. Activated in Windows 2000 by selecting Obtain An IP Address Automatically 3. DHCP server a. An application that processes requests from DHCP clients b. Implemented on most server operating systems, including Windows 2000, Microsoft Windows NT, Novell NetWare, and UNIX 4. DHCP protocol a. Used for communications between clients and servers|8| 5. DHCP supports three types of IP address allocation: manual, automatic, and dynamic.|9| 6. Manual allocation a. You assign a specific IP address to a computer in the DHCP server and the server provides that address to the computer when it is requested. b. Functional equivalent of BOOTP address assignment c. Most labor intensive d. Provides permanent IP address assignments for computers that need them, such as Internet servers e. Using DHCP instead of manual configuration for permanent assignments prevents addresses from being duplicated.|10| 7. Automatic allocation a. The DHCP server supplies clients with IP addresses taken from a common pool of addresses, and the clients retain the assigned addresses permanently. b. Suitable for networks where computers are rarely moved to other subnets c. Minimizes network traffic generated by DHCP|11| 8. Dynamic allocation a. Enables administrators to add, remove, and relocate computers2 Outline, Chapter 10 Network+ Certification, Second Edition b. The DHCP server uses a pool of addresses to lease IP addresses to clients. (1) The client must periodically renew the lease or else the address returns to the pool for reallocation. c. Completely automates the TCP/IP configuration process D. DHCP message format 1. All DHCP traffic uses a single message format ...