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== Fields == |
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*ID: 2 Bytes Identifier: |
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A 16-bit identification field generated by the device that creates the DNS query. |
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It is copied by the server into the response, so it can be used by that device to match that query to the corresponding reply received from a DNS server. |
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This is used in a manner similar to how the Identifier field is used in many of the ICMP message types. |
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*QR: 1/8 (1 bit) Query/Response Flag: |
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Differentiates between queries and responses. |
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Set to 0 when the query is generated; changed to 1 when that query is changed to a response by a replying server. |
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*Opcode: 1/2 (4 bits) |
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Specifies the type of query |
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Set by creator of the message |
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Copied unchanged into Response |
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0 Query |
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1 IQuery |
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2 Status |
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3 (Reserved) |
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4 Notify |
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5 Update |
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*AA: |
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*TC: |
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*RD: |
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*RA: |
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*Z: |
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*RCode: |
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*QDCount: |
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*ANCount: |
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*NSCount: |
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*ARCount: |
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== Flags == |
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* Recursion Desired Field |
* Recursion Desired Field |