Many ISPs, particularly residential, block ports to control traffic or protect their users. This means that if you want to run a webserver from your home and your ISP has blocked port 80 then you have to jump through some hoops to make it happen. How do you know if port 80 (or some other port you need) is blocked? Use the Can you see me? service.
Husband to one wonderful wife, father to five fantastic children, juggler, technophile, freelancer, DIYer, adventurer, volunteer
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