guy-atkinson
Uploaded by
21 SLIDES
369 VUES
210LIKES

MIS 4700

DESCRIPTION

MIS 4700. Dynamic Host Configuration Protocol (DHCP) Part 1. Introducing DHCP. Provides a way for client computer to request an IP address DHCP delivers the necessary configuration information IP address Subnet mask IP Gateways Address for DNS servers Address for WINS servers.

1 / 21

Télécharger la présentation

MIS 4700

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. MIS 4700 Dynamic Host Configuration Protocol (DHCP) Part 1

  2. Introducing DHCP • Provides a way for client computer to request an IP address • DHCP delivers the necessary configuration information • IP address • Subnet mask • IP Gateways • Address for DNS servers • Address for WINS servers

  3. Introducing DHCP (cont.) • Administer client IP address assignments and configuration data from a single, centralized server • Address pool or address scope • One or more range of IP address • Exclude an address or range of address • Address lease

  4. How DHCP Works • Client perspective on DHCP • Client is configured to “Obtain an IP address automatically” • At boot-up the client broadcasts DHCP address request • DHCP servers reply offers an address lease • Client accepts address lease offer • Server offers an IP address with a lease time limit • Half the lease time the client attempts to renew lease

  5. How DHCP Works (cont.)

  6. The Role Of Leases • Length of leases vary • One to three weeks in length are typical • One to three days for networks with temps or roving workers • Four to eight hours are common on ISP networks

  7. DHCP Software Elements • Three elements to DHCP software • DHCP client • Built-in DHCP client software in Windows and UNIX operating systems • DHCP Server • Manages address pools and related configuration of Windows and UNIX servers • DHCP relay agent • Intercepts address requests • Repackages requests and unicasts to a DHCP server

  8. DHCP Lease Types • Two types of address leases • Manual address lease • Dynamic address lease • Typical IP addressing schemes • Servers have fixed IP addresses • Routers have fixed IP addresses • Clients use dynamic IP Addresses

  9. More About DHCP Leases • IPCONFIG command supports the /release and /renew switches • How DHCP integrates with DSN • Server address are advertised using DNS • DNS is not a dynamic environment • Client address are resolved when using email addresses • User@domain.name

  10. Understanding IP Address Management With DHCP • Booting for the first time or after a lease expires • DHCP Discovery • Discovery broadcast • Renewal process • Rebinding process • Client must completely release its address if rebinding fails • Servers and clients use PING and ARP as error prevention methods

  11. The Standard Address Discovery Process • DHCP Discovery process uses four packets • DHCP Discover packet • DHCP Offer packet • DHCP Request packet • DHCP Acknowledgment packet

  12. The Standard Address Discovery Process (cont.)

  13. The Discover Packet • Client broadcasts a Discover Packet • Client hardware address • Source IP address 0.0.0.0 • Destination address 255.255.255.255 • Preferred address • Message Type value 1 • Client Identifier • DHCP options

  14. The Discover Packet (cont.) • DHCP options • Option 1: Client’s subnet mask • Option 3: Routers on the client’s subnet • Option 6: Domain name servers • Option 15: Domain name • Option 44: NetBIOS over TCP/IP name servers • Option 46: NetBIOS over TCP/IP node type • Option 47: NetBIOS over TCP/IP scope • Option 57: Maximum DHCP message size • Option 255: End of options

  15. The Discover Packet (cont.)

  16. The Offer Packet • DHCP server sends the Offer packet • An IP address is offered • Packet is sent by unicast

  17. The Offer Packet (cont.)

  18. The Request Packet • DHCP Request packet • DHCP Decline packet

  19. The Request Packet (cont.)

  20. The Acknowledgment Packet • Sent from Server • Contains configuration options requested by client • Duplicate IP address test

  21. The Acknowledgment Packet (cont.)

More Related