Routers must be configured

iVisit will work with many routers and firewalls without any special configuration, as long as the router/firewall is configured to allow all "outbound services". If you find that you cannot logon to iVisit then your router/firewall must be configured to allow outbound UDP session. You will need to configure it to allow outbound traffic on UDP port 9940 and UDP port 9943.

This should allow you to reach the iVisit servers and logon. However, with some types of routers, you may also need to establish iVisit as an "inbound service" in order to connect to other users. This means that inbound traffic from the Internet that is directed to the iVisit port, will be accepted by the router and forwarded to a pre-specified host which you choose.

If you are using a router that requires this special configuration, iVisit will detect this and show an alert dialogue when you first log on. If you see this alert, but do not configure your router, then you will find that you cannot connect to some people (e.g., if they are also using this type of router). If you are able to logon and do not see this alert, then you probably do not need to configure your router (but bear in mind that the alert has a "Don't show me this again" checkbox, so it may be that someone else has seen the alert on your machine and disabled it).

The main requirement for iVisit is that traffic to/from UDP port 9940 on the local iVisit client must be allowed to pass through the router. The router may remap this port to a different port on the public ("WAN") side without causing any problems, as long as the routers maintains a consistent 1:1 mapping: (private address,UDP port 9940) <-> (public address,UDP port X)

If your router behaves this way, then you can easily run iVisit on more than 1 client machine behind the router, and without any special configuration. The router will just choose a different X for each iVisit client you have running. However, some routers will choose a different port X for each remote host which a single iVisit host tries to communicate with. These are the kind that cause problems; the only way to insure a consistent 1:1 mapping is to configure UDP port 9940 as an inbound service. Unfortunately, this means that only 1 iVisit client may be active at a time (and you must reconfigure the router if you wish to use iVisit on a different machine).