NLSR

Currently Map uses a std::list, which is only optimal for insertion. Generally speaking, C++ encourages the use of std::vector as the "general purpose" container. However, each name must be unique, so an unordered set would be better. However, since we need lookup on two indices (name and mapping number), we can use a Boost multi_index container.

Alternatively, we could make the mapping number a function of the router name, and then the router name actually can be used as both keys. Currently, mapping numbers are sequentially assigned.