I have got some major problems with pinging each and every host in the hostcount:
- Not all hosts respond to a ping (PCs for instance) but are part of the Internet in my view. Given the large amounts of PCs around, this will pull your figure down.
- Not all hosts are reachable from all parts of the Internet (AUP, firewalls, access filters).
Fully agreed. My reasoning for wanting this number is that it gives a good and trustworthy lower bound on the number of network interfaces connected (the "real" number will not be lower than this measurement). As to the validity of the current number, you know just as good as I do that we have no idea how "real" this is. For example a number of the largest IP users in Switzerland are customers of ours, however since they run seperate external DNS servers their host count is probably only three orders of magnitude to low. On the other hand it's just so easy to fake the numbers (want to overtake your competition? A 10 second shell script will do the job). The ping numbers would allow us to get some idea on how good the DNS counts are. At least in the larger countries we can expect roughly the same ratio of PC's/Macs/Workstations/etc. and can investigate when DNS count/reachable hosts is totally off. Simon