The level of information often depends on the thoroughness of the organisation if they have provider independant (PI) IP space, or the thoroghness of the local internet registrar (LIR) if they have provider aggregated (PA) IP space.
From a whois search on the IP you
should be able to get valid information for the organisation actually using the IP (this is a requirement made by the regional internet registrars (RIR) [at least in Europe, RIPE's authority]). However often these records are ambiguous or outdated as they are not updated as regularly as they should be. Also some larger LIR routinely assign IP space from a large allocation (typically a /19-/24) and only update the whois records for the parent block.
Another useful tool for recon work is
myipneighbors/, as it allows you to find other domains using the same IP. This is useful for services running virtual hosts on the same server or shared colocation environments.
It's worth noting that the above techniques do not cause any traffic to reach the target from your IP address, so they are silent in that regard. Obviously once you start stepping up a gear with port enumeration and banner grabbing etc. this changes completely.
Hope this is some help.
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