On the scope of NHDP-sec-threats

Regarding the common attacks, the idea is that it's necessary to include the common threats in wireless networks that are remarkable in MANET neighbor discovery procedure. It's inevitable to have some overlaps with other threat documents, but we think it's worth to emphasize those critical threats for NHDP. 

Currently, we have the jamming and eavesdropping in the document. For jamming, it is an important attack vector in this kind of decentralized environment because of restricted resource, especially when the HELLO message can be triggered by state change of the network - which is further discussion in the "indirect jamming" section.  For eavesdropping, it provides network information required for enabling other attacks, such as link/node spoofing, which are introduced in later sections. 

The current revision of the document also includes a section for the impacts on protocols using NHDP. The rationale is that, as a neighbor discovery protocol, NHDP is used in combination with other protocols most of the time. Therefore, the document describes how the those protocols might be disrupted by the misbehavior of NHDP (in common sense, such as MPR calculation, data sinkhole, etc. ). If we are going to produce more threats documents in the future, there is no need to worry about those common ones in NHDP (for example, we probably don't want to discuss the threats in MPR selection in both SMF-threats and OLSRv2-threats).