> -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of > Girish Venkatachalam > Sent: 12 October 2006 11:57 AM > To: misc@openbsd.org > Subject: Simple Networking Newbie questions > > Friends, > > I am a newbie to certain real world networking concepts since I have > no hands on experience in network deployments. > > And OpenBSD man pages unfortunately are not clear enough for me. > Perhaps I am daft but I would gladly rewrite them for the benefit of ppl > like me... > > I also read FreeBSD man pages, googled and read wikipedia too. Still > no joy. > > Anyway I have few more questions, but let me begin with these. > > 1) What exactly is the difference between tun(4), gif(4) and gre(4) > interfaces? > > As I understand it, gre is a Cisco tunneling mechanism for generic > IP encapsulation. tun is a generic network device useful for setting up > tunnels, but how? > > And gif can be used for setting IP in IP tunnels. > > But frankly I am not able to get any further with these statements. > > How are these interfaces used in practice? I know that gre is useful > for PPTP traffic. > > And that gif can be used for IP in IP for instance, something like > IPsec. What about tun(4)? Is it used as a tunnel interface mechanism from > user space? > > Cant you have IPsec without using gif(4)? You can , right? > > 2) My second question relates to vlan(4). Is my understanding that > you can extend ethernet segments logically across the Internet with vlans > correct? I am sure there is much more to it. I am getting some idea from > recent threads but I am interested in more practical anecdotes as to where > it is really useful. > > I guess vlans can also be used to split an ethernet broadcast domain > into multiple subnets. Does it help to do this for running pf on VLAN > bridges? > Please be gentle if my questions are outright nonsensical. > > I think my other doubts on bridging, trunking etc. are not that > troublesome since I seem to have an idea about them. > > Many thanks to everyone for taking time to read my e-mail. > > regards, > Girish
I use tun for ppp and gprs connections.
