SIP Termination

I would like to originate calls from * box to some other termination gateways like Cisco or others, i guess they are usinh H.323 and G.723 codec. in this case how can i get connected to them, how the setup or codec conversion will look like.
please let me know how this could be done.

Happy new year to everybody.

Asterisk does not work with G.723 out of the box and it is probably a lost cause to even try due to licensing costs. Asterisk will work with H323 but it is non-trivial to get working.