What's the best way to monitor traffic?

I’m wondering what the best way to monitor traffic is? At the moment I’m using vnstat, and vnstati(I dump the graphs to the built in webserver directory). Is there a standard way of logging traffic(not a router expert)?

It really depends on precisely what you mean by “monitor traffic”, but netflow is very handy.

I am fairly new to most of these opensource tools, but when I need to do some live monitoring, or daily monitoring of hardware devices, I use Iptraf. I prefer using the hardware monitor, so I can see the overall traffic going through a specific MAC, rather than the bulk of IP addresses and ports associated with different connections. But the purpose for which I use Iptraf is to monitor bandwidth abusers. Now, if I was looking for ports and what not, then I would monitor a specific interface or use other tools like netwatch.