A router is a piece of equipment that some people use to connect multiple computers to a single connection or to network a group of computers.
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If your friend/ relation has a problem with his/ her connection then if you get a few details from him/ her we might be able to suggest something.
Basics like what operating system is he/ she running,
how is the computer connected to the BB feed (SACM or STB)
is it connected via a router, 2nd pc etc,
is it connected via USB or ethernet,
is he/ she running a firewall,
what is the actual connection problem?