Question on DHCP networking?

Question

Hi,

I'm a beginner trying to learn a bit about computer networking and I just have a few questions for a packet capture. I have linked the picture of the packet capture below.

In this I'm looking at a DHCP handshake, which if I'm correct starts at frame 9. After the discover and offer, what is the address of the next hop?

and what are the DNS servers?

http://iforce.co.nz/i/ywrzrcoa.xlk.jpg

Answer 1

Yes, DHCP starts at frame 9



DHCP DISCOVER - Broadcast to find a DHCP server for IP configuration



DHCP OFFER - DHCP server offers IP configuration. This is also sent as a broadcast as the host isn't connected to the network. It also notifies other devices, particularly other DHCP servers, that the offer has been sent. The server is also likely to ping the address first to make sure it's not been manually assigned to another PC.



DCHP REQUEST - Request sent to accept the offer. Broadcast for other devices to update ARP tables etc. There may also be another ping here to prevent errors.



DHCP DECLINE - In the event of multiple servers sending offers, all will be declined after the first is accepted.



DHCP ACK - Acknowledgement that the IP has been assigned and is working



DHCP NACK - in the unlikely event of an error a NACK will be sent to void the offer. If this happens the process begins again with DHCP DISCOVER





DNS servers are name servers that convert IP addresses to hostnames or hostnames to IP addresses.



When you type in a URL the URL is sent to the DNS server which replies with the IP address of the site. When a host recieves the IP it can begin sending packets to the IP address and will save the address in it's DNS cache in case it's needed again.

Answer 2

Dynamic Host Configuration Protocol (DHCP) is a client/server protocol that automatically provides an Internet Protocol (IP) host with its IP address and other related configuration information such as the subnet mask and default gateway. RFCs 2131 and 2132 define DHCP as an Internet Engineering Task Force (IETF) standard based on Bootstrap Protocol (BOOTP), a protocol with which DHCP shares many implementation details. DHCP allows hosts to obtain necessary TCP/IP configuration information from a DHCP server.

The Microsoft Windows Server 2003 operating system includes a DHCP Server service, which is an optional networking component. All Windows-based clients include the DHCP client as part of TCP/IP, including Windows Server 2003, Microsoft Windows XP, Windows 2000, Windows NT 4.0, Windows Millennium Edition (Windows Me), and Windows 98.



In Windows Server 2003, the DHCP Server service provides the following benefits:

Reliable IP address configuration. DHCP minimizes configuration errors caused by manual IP address configuration, such as typographical errors, or address conflicts caused by the assignment of an IP address to more than one computer at the same time.



Reduced network administration. DHCP includes the following features to reduce network administration:



Centralized and automated TCP/IP configuration.



The ability to define TCP/IP configurations from a central location.



The ability to assign a full range of additional TCP/IP configuration values by means of DHCP options.



The efficient handling of IP address changes for clients that must be updated frequently, such as those for portable computers that move to different locations on a wireless network.



The forwarding of initial DHCP messages by using a DHCP relay agent, thus eliminating the need to have a DHCP server on every subnet.

Answer 3

OH NO YOU AREN'T YOU'RE CROWD SOURCING YOUR ANSWERS TO THE ASSIGNMENT.