| OSPF Database Description Packet |
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0 | 1 |
| 2 | 3 | 4 |
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| Version No. |
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| 2 |
| Packet Length |
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| Router ID |
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| Area ID |
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| Checksum |
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| Authentication Type |
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| Authentication |
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| Authentication |
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| Reserved |
| I | M | MS |
| Reserved |
| Options |
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| DD Sequence No. |
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| Figure 6- 102. Database Description Packet |
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Field | Description |
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Options | The optional capabilities supported by the router. |
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I – bit | The Initial bit.When set to 1, this packet is the first in the sequence of Database Description packets. | ||||||||||||
M – bit | The More bit.When set to 1, this indicates that more Database Description packets will follow. | ||||||||||||
MS – bit | The Master Slave bit.When set to 1, this indicates that the router is the master during the Database Exchange | ||||||||||||
DD Sequence Number | process.A zero indicates the opposite. |
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User to sequence the collection of Database Description Packets.The initial value (indicated by the Initial bit | |||||||||||||
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| being set) should be unique.The DD sequence number then increments until the complete database | |||||||||||
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| description has been sent. |
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The rest of the packet consists of a list of the topological database’s pieces. Each link state advertisement in the database is described by its link state advertisement header.
Link-State Request Packet
A router that sends a
The format of the
Allied Telesyn | 110 |