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LocalControlHeader » History » Version 3

Alex Afanasyev, 01/31/2014 11:43 PM

1 1 Junxiao Shi 
# NFD local control header
2 3 Alex Afanasyev 





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NFD local control header can be used between application and local forwarding daemon to exchange various NFD-specific local information that is not part of Interest and Data packet.





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For example, the control header allows applications to request bypassing the Interest forwarding strategy by directly specify FaceId to which the Interest should be forwarded.





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NFD local control header is not enabled by default and requires explicit request from the client to enable.





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This request is in form of [[Signed_Interests|Signed Interest]] and have the following structure:





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    /localhost/nfd/control-header/<command-verb>/<timestamp>/<SignatureInfo>/<SignatureValue>





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    \                            / \           / \                                          /





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     ------------  ------------     ----  -----   --------------------  --------------------





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                 \/                     \/                            \/





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       NFD Control Command         "enable" or       Signed Interest related information





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                                    "disable"





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## LocalControlHeader





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If command to enable LocalControlHeader is authorized by NFD, all subsequent communication from NFD will include LocalControlHeader as defined below.





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The authorized application will also be able to include LocalControlHeader in communication to NFD---until specifically enabled, all specified LocalControlHeaders should be ignored by NFD.





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    LocalControlHeader ::= LOCAL-CONTROL-HEADER-TYPE TLV-LENGTH





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                             LocalControlInfo





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                             (Interest | Data)





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    LocalControlInfo   ::= LOCAL-CONTROL-INFO-TYPE TLV-LENGTH





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                             FaceId?





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## TLV-TYPE assignments





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Type                                        | Assigned value    | Assigned value (hex)





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------------------------------------------- | ----------------- | --------------------





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LocalControlHeader                          | 109               | 0x6d





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LocalControlInfo                            | 110               | 0x6e





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FaceId                                      | 105               | 0x69