LocalControlHeader » History » Revision 4
Revision 3 (Alex Afanasyev, 01/31/2014 11:43 PM) → Revision 4/26 (Alex Afanasyev, 02/05/2014 04:26 PM)
# NFD local control header
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.
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.
NFD local control header is not enabled by default and requires explicit request from the client to enable.
This request is in form of [[Signed_Interests|Signed Interest]] and have the following structure:
/localhost/nfd/control-header/<command-verb>/<timestamp>/<SignatureInfo>/<SignatureValue>
\ / \ / \ /
------------ ------------ ---- ----- -------------------- --------------------
\/ \/ \/
NFD Control Command "enable" or Signed Interest related information
"disable"
## LocalControlHeader
If command to enable LocalControlHeader is authorized by NFD, all subsequent communication from NFD will include LocalControlHeader as defined below.
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.
LocalControlHeader ::= LOCAL-CONTROL-HEADER-TYPE TLV-LENGTH
LocalControlInfo
(Interest | Data)
LocalControlInfo ::= LOCAL-CONTROL-INFO-TYPE TLV-LENGTH
(IncomingFaceId |
OutgoingFaceId |
TapInfo)
IncomingFaceId ::= INCOMING-FACE-ID-TYPE TLV-LENGTH
nonNegativeInteger
OutgoingFaceId ::= INCOMING-FACE-ID-TYPE TLV-LENGTH
nonNegativeInteger
TapInfo ::= TAP-INFO-TYPE TLV-LENGTH
...
(TBD) FaceId?
## TLV-TYPE assignments
Type | Assigned value | Assigned value (hex)
------------------------------------------- | ----------------- | --------------------
LocalControlHeader | 109 | 0x6d
LocalControlInfo | 110 | 0x6e
IncomingFaceId FaceId | 111 105 | 0x6f 0x69
OutgoingFaceId | 112 | 0x70
TapInfo | 113 | 0x71