Fax July 1996. A major breakthrough in the development of the modern facsimile system was the result of digital technology, where the analog signal from scanners was digitized and then compressed, resulting in the ability to transmit high rates of data across standard phone lines. The first digital fax machine was the Dacom Rapidfax first sold in late 1960s, which incorporated digital data compression technology developed by Lockheed for transmission of images from satellites. Group 3 and 4 faxes are digital formats, and take advantage of digital compression methods to greatly reduce transmission times. Fax Over IP (FoIP) can transmit and
Junk fax transmitting organization or individual on each page. The process of war dialing to determine what phone numbers reach fax machines was also prohibited by the FCC rules under the TCPA. The TCPA, in particular the junk fax provision, has been challenged in court on First Amendment grounds, but the law has withstood legal challenges. In 2005, the United States Congress passed the Junk Fax Prevention Act of 2005. It amended the TCPA so as to no longer prohibit unsolicited fax advertisements if: and the sender complies with other requirements. In April 2006, the Federal Communications Commission (FCC) implemented changes to