[LARTC] a bit confused

[Przemekk]

hello there
first of all - yes, I've read LARTC Howto;
             - yes, I've google'd a bit
secondly - if i miss smth. please give me a pointer to some source of info, instead of shouting at me 

clue:
from LARTC Howto
[...]
The frame is actually the unit on which traffic control is performed.
[...]

so when i'm shaping with htb ( and fe. sfq ), the kernel is 'slowing' rate of frames in Layer 2, so setting htb rate to 2mbit means 'set the speed of frames ( not packets ) to 2mbit'; on the other hand, filters  are using at least Layer 3 infos ( adresses, port numbers, etc.; or MARKs which have been set via iptables, but based on at least L3 info );

1st question - are these top statements right?
2nd question - how is this connected in kernel ( shaping frames, but using higher layers infos)
3rd question - probably ntg, but perhaps someone knows smth: iptables -L -vnx shows amount of bytes including ethernet header and trailer, or only size of IP packets ( incl. payload, of course )?

thanks in advance

przemek.krol 

-- 
-------
	chaos, panic and disorder ...
	looks like my work is done here
					-------