Screeching occurs during handshaking. During the handshaking, the frequency is audible, thats the reason for screeching. > -----Original Message----- > From: Bill Cunningham [SMTP:billcu@citynet.net] > Sent: Tuesday, June 11, 2002 12:53 PM > To: ietf@ietf.org > Subject: modems > > I know modems communicate on the physical layer by electrical pulses or > binaries sent on copper wires. Is that screeching you hear electrical > communication? Computers don't communicate by screeching...or do they? >