This arc is, among other things, used to assign OIDs in drafts of SNMP MIBs. These numbers are then changed before publishing the MIB as an RFC.
Information:
Excerpts from IETF RFC 1155:
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3.1.3. Experimental
The experimental(3) subtree is used to identify objects used in Internet experiments. Administration of the experimental(3) subtree is delegated by the IAB to the Internet Assigned Numbers Authority of the Internet.
For example, an experimenter might received number 17, and would have available the OBJECT IDENTIFIER {experimental 17} or 1.3.6.1.3.17 for use.
As a part of the assignment process, the Internet Assigned Numbers Authority may make requirements as to how that subtree is used.
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