Here is a list of some communication software you can choose from, available via FTP, if they didn't come with your distribution.
ecu - a communications programminicom - telix-like communications program procomm - procomm-like communications program with zmodemseyon - X based communication programxc - xcomm communication package
term and SLiRP. They offer
TCP/IP functionality using a shell account.
screen is another multi-session program. This one behaves
like the virtual consoles.
callback is a program that will have your modem call you back.
mgetty+fax handles FAX stuff, and provides an alternate
ps_getty.
ZyXEL is a control program for ZyXEL U-1496 modems. It
handles dialin, dialout, dial back security, FAXing, and voice
mailbox functions.
ftp://sunsite.unc.edu/pub/Linux/system/network/serial.
ftp://sunsite.unc.edu/pub/Linux/system/serial and
ftp://sunsite.unc.edu/pub/Linux/apps/serialcomm or one of the
many mirrors. These are the directories where serial programs are kept.