[talk] pf.conf bowtie operator

[Mark Saad]

All
  I have seen the bowtie operator a few times in use on both freebsd and openbsd pf setups but I cant find what it does exactly.
For example from  https://rlworkman.net/howtos/OpenBSD_pf_guide.html

pass out on $ext_if inet proto udp from any to any port 33433 >< 33626 keep state

So my two questions;  When I setup a pf udp rule where I expect to get data back from the sender do I need 
to use the keep state option, my gut says yes . When trying to figure out how to do static port mappings I 
ran into that bowtie and I am at a loss as to what that does; would static-port $MYTARGETPORT  work better ?
Any out there know ?

--
 Mark Saad
 mark.saad at ymail.com