What are the statistics on port 22 blocking by firewalls in small and medium sized enterprises? We have a product that a customer installs on a PC, which communicates via ssh to our cloud server. It would be good to know how common port 22 blocking is.
Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise.If this question can be reworded to fit the rules in the help center, please edit the question.
TCP/22 blocking is common enough you should have documentation in your product, or it's support site, at release describing why this is needed. When requirements assessment is done at a customer, this sort of information up front can turn aside some nasty complaints after deployment and they find it doesn't work.
Aggressive egress filtering is much more common in some industries than others, so there will be variation depending on who you're selling to. However, ultra-paranoids can crop up anywhere so be ready for it.