difference on syntax

hi.

1) What is the difference between :

(fxp0 is my wan interface and 192.168.0.1/24 is my lan network)

pass in on fxp0 proto tcp/udp from any to any keep state
pass in on fxp0 proto icmp from any to any keep state

and

pass in quick proto icmp from 192.168.0.0/24 to any keep state
pass in quick proto tcp from 192.168.0.0/24 to any keep state
pass in quick proto udp from 192.168.0.0/24 to any keep state

It's just a question of precision ?

2) Other question.
I see

pass in quick proto icmp from 192.168.0.0/24 to any keep state
pass in quick proto tcp from 192.168.0.0/24 to any keep state
pass in quick proto udp from 192.168.0.0/24 to any keep state
pass in quick from 192.168.0.0/24 to any

or

map tun0 from 192.168.1.0/24 to 0.0.0.0/0 -> xx.xx.xx.x/32 portmap
tcp/udp auto
map tun0 from 192.168.1.0/24 to 0.0.0.0/0 -> xx.xx.xx.x/32

What is the interest to put this line :
pass in quick from 192.168.0.0/24 to any
or
map tun0 from 192.168.1.0/24 to 0.0.0.0/0 -> xx.xx.xx.x/32

3) Time restrict
I am surprised to see that with Iptables:
$IPTABLES -A INPUT -s 192.168.0.0/24 -m state --state NEW -m time
--timestart 08:00 --timestop 12:00 --days Sun,Mon,Tue,Wed,Thu,Fri,Sat -j
ACCEPT
$IPTABLES -A OUTPUT -s 192.168.0.0/24 -m state --state NEW -m time
--timestart 08:00 --timestop 12:00 --days Sun,Mon,Tue,Wed,Thu,Fri,Sat -j
ACCEPT
$IPTABLES -A FORWARD -s 192.168.0.0/24 -m state --state NEW -m time
--timestart 08:00 --timestop 12:00 --days Sun,Mon,Tue,Wed,Thu,Fri,Sat -j
ACCEPT


It's possible to do that with ipfilter without use squid ?

Nicolas M.