:* '''Outbound traffic ''' from a server (like a response to the Firefox web-browser from the web-server) '''is rarely blocked <u>unless</u> there is a security policy to <u>prevent</u> some kind of traffic'''. Even in that case, that security policy is usually performed on a router (this is a topic which will be discussed later in this course).

:* '''Inbound traffic is of two distinct types, in our '''. Our diagram we have bothshows:::# '''New incoming connections ''' (what you normally think of as '''inbound traffic'''): the web server receives a new incoming connection.::# '''Incoming data that's a response to a request''': the web page that the server sent back in the diagram above.::# <br><br>We normally don't want to do anything special for the response. It's a is safe assumption to assume that '''a connection that was allowed to be established should be allowed to receive a response'''. This is accomplished with the following INPUT chain rule that should be there by default on your machines:<br><br>