Asterisk startup

i need to record call coming from outside, Please tell me whether astersik will be effective for it and also tell me for connecting it to external PSTN.

To connect with external PSTN, in the starting phase i want to use cards, what are the cards to use?

;
;This will record incoming calls; the file name will include the date, callerID and extension
;
exten => s,1,Answer()
exten => s,2,Set(CALLTIMESTAMP=${STRFTIME(${EPOCH},%y-%m-%d-%H%M)}-${CALLERID(num)}-${EXTEN:0})
exten => s,3,Set(CALLFILENAME=${CALLTIMESTAMP})
exten => s,4,Monitor(wav,${CALLFILENAME},m)
exten => s,5,Dial(SIP/302,45)
exten => s,6,Congestion()

  1. Cards
    Depends on what you need/want to achieve; minimum TDM400P (4 Lines).
    Take a look at www.digium.com

Thank u very much, i will implement this with ur ideas.