asterisk users - May 2011 - About minimum requirements to install PSTN GW+SIP Client

Dear all,

Could you teach me minimum required Asterisk modules, application and etc to
install PSTN GW+SIP Client functionalities in a PC as shown below? I have
already downloaded astersik-1.8.3.3 and dahdi-linux-complete-2.4.1.2+2.4.1 in
the PC.

Analog telephone --- PSTN GW + SIP Client --- SIP Server
                     ********************
                             PC

Since available memory in the PC is very low, I have to select minimum
requirements on screen "Asterisk Module and Build Option Selection"
diplayed by executing make menuselect on console. First, I have selected
chan_dahdi, chan_local and chan_sip as Channel Drivers on the screen, but
don't understand that what are required in Applications, Resource Modules
and etc on it to satisfy the above functionalities.


Regards,
Yagishita