Originally posted by: pelikan
Yes zone alarm affects the speed of your system. If you want a firewall that affects speed as little as possible you want the xp firewall.
It will probably not be that noticable, anyway.
Originally posted by: hatim
Whats the diffenece b/w a hub and a router?
A hub is a dumb device, it purely takes the data coming in a port, cleans it up/amplifies it, and sends it out of all ports.
A switch (even though you didn't ask

) is almost the same as a hub, but instead of sending it out of all ports, it sends it out only the one that it needs to.
A Router allows you to communicate with other networks, with different network address ranges, or in SOHO (small office home office) devices, allow you to share internet connections with more than 1 PC. Most SOHO routers include a switch. SOHO routers use Network Address Translation (NAT) to share the network connection, and the NAT process is also a kind of firewall (ie it won't allow data in unless it has been requested from inside the network).
However, that still won't protect your computer from sending out malicious messages (Ie "phoning home"), nor will the Windows XP firewall.
Your best bet will be something like ZoneAlarm, as i said earlier, it shouldn't affect your speed in a noticable way
Confused