I am looking for hardware in order to install Asterisk in a small company. What they actually need is to use the existing infrastructure which is an ISDN line and a PSTN line, along with 7 plain telephone devices. Also there is a ADSL modem - router which connects the company to the Internet, so VoIP capabilities should be considered. Also a modem for fax purposes is a must, since all faxes go now by hand (is this evitable?).
Please let me know what kind of hardware I should purchase for this purpose because I am a bit confused regarding the cards that are out there.
Thank you in advance.