NOTE: Using software to mass-download the site degrades the server and is prohibited.
If you want to read The TCP/IP Guide offline, please consider licensing it. Thank you.

The Book is Here... and Now On Sale!

Read offline with no ads or diagram watermarks!
The TCP/IP Guide

Google
Web TCP/IP Guide






Table Of Contents  The TCP/IP Guide
 9  TCP/IP Lower-Layer (Interface, Internet and Transport) Protocols (OSI Layers 2, 3 and 4)
      9  TCP/IP Internet Layer (OSI Network Layer) Protocols
           9  TCP/IP Routing Protocols (Gateway Protocols)
                9  TCP/IP Interior Routing Protocols (RIP, OSPF, GGP, HELLO, IGRP, EIGRP)
                     9  Open Shortest Path First (OSPF)

Previous Topic/Section
OSPF General Operation and Message Types
Previous Page
Pages in Current Topic/Section
12
3
4567
Next Page
 Other Interior Routing Protocols
Next Topic/Section

OSPF Message Formats
(Page 3 of 7)

Database Description Message Format

These messages have a Type value of 2 in the header, and the body structure depicted in Table 128 and Figure 186.


Table 128: OSPF Database Description Message Format

Field Name

Size (bytes)

Description

Interface MTU

2

Interface MTU: The size of the largest IP message that can be sent on this router's interface without fragmentation.

Options

1

Options: Indicates which of several optional OSPF capabilities the router supports.

Flags

1

 

DD Sequence Number

4

DD Sequence Number: Used to number a sequence of Database Description messages so they are kept in order.

LSA Headers

Variable

LSA Headers: Contains link-state advertisement headers, which carry information about the LSDB. See near the end of the topic for more information on LSAs.


Figure 186: OSPF Database Description Message Format

 

Previous Topic/Section
OSPF General Operation and Message Types
Previous Page
Pages in Current Topic/Section
12
3
4567
Next Page
 Other Interior Routing Protocols
Next Topic/Section

If you find The TCP/IP Guide useful, please consider making a small Paypal donation to help the site, using one of the buttons below. You can also donate a custom amount using the far right button (not less than $1 please, or PayPal gets most/all of your money!) In lieu of a larger donation, you may wish to consider purchasing a download license of The TCP/IP Guide. Thanks for your support!
Donate $2
Donate $5
Donate $10
Donate $20
Donate $30
Donate: $


Home - Table Of Contents - Contact Us

The TCP/IP Guide (http://www.TCPIPGuide.com)
Version 3.0 - Version Date: September 20, 2005

© Copyright 2001-2005 Charles M. Kozierok. All Rights Reserved.
Not responsible for any loss resulting from the use of this site.