[Nfd-dev] A Potential Conflict in Developer Guide about FIB Entry's NextHop Collection

[Ju Pan]

Dear folks,

In NFD Developer Guide, there is a potential conflict in the
description about a Fib entry's nexthop collection.

1. In Chapter3 Tables --> 3.1 Forwarding Information Base (FIB) -->
3.1.1 Structure and Semantics
--> FIB entry and NextHop record, it says:

"A FIB entry (nfd::fib::Entry) contains a name prefix and a non-empty
collection of NextHop records."
(It says a FIB entry contains a non-empty collection of NextHop
records, in 3.1.2 Usage part, it says a FIB entry losing its last
nexthop record is deleted.)

2. In Chapter 4 Forwarding --> 4.5 Helper Algorithms --> 4.5.1 FIB
lookup --> 1, it says:

"FIB guarantees that Longest Prefix Match returns a valid FIB entry;
however, a FIB entry may contain empty set of NextHop records, which
could effectively result (but, strictly speaking, is not required to
happen) in the strategy rejecting the Interest."
(It says a FIB entry may contain an empty set of NextHop records.)

I think the actual NFD was implemented as the former way. (erase the
Fib entry if it doesn't have any nexthop)

Could someone confirm this conflict or point out what did I
misunderstand? Thanks.

Regard,
Ju