ALOHAnet was an over-the-air wide area network system in Hawaii using ultra high frequency radios and made several assumptions that Metcalfe thought would not be correct in practice.

In 1972, he joined Xerox PARC to develop these ideas, and after pairing up with David Boggs, the two had early 3 Mbit/s versions of Ethernet working in 1973.

They then went on to build up a networking protocol known as PARC Universal Packet (PuP), with the entire system ready for build-out by late 1974.

In the mid-1980s, 3Com branded their Ethernet technology as EtherSeries, while introducing a range of software and PC-based equipment to provide shared services over a local area network (LAN) using XNS protocols.

These protocols were branded EtherShare (for file sharing), EtherPrint (for printing), EtherMail (for email), and Ether-3270 (for IBM host emulation).

This provided a range of equipment based on Motorola 68000 processors and using XNS protocols compatibly with 3Com's Etherterm PC software.

By 1995, 3Com's status was such that they were able to enter into an agreement with the city of San Francisco to pay $900,000 per year for the naming rights to Candlestick Park.

3Com continued the development of the Total Control line until it was eventually spun off as a part of Commworks, which was then acquired by UTStarcom.

In the lucrative server network interface controller (NIC) business, 3Com dominated market share, with Intel only able to break past 3Com after dramatic price slashing.

As one of the first companies to deliver a complete networked phone system, and increased its distribution channel with larger telephony partners such as Southwestern Bell and Metropark Communications, 3Com helped make VoIP into a safe and practical technology with wide adoption.

3Com then tried to move into the smart consumer appliances business and in June 2000, 3Com acquired internet radio startup Kerbango for $80 million.

In March 2000, in a highly public and criticized move, 3Com exited the high-end core routers and switch market to focus on other areas of the business.

3Com focused its efforts from 2000 to 2003 on building up the HomeConnect, OfficeConnect, SuperStack, NBX and Total Control product lines.

In September 2007, Bain Capital agreed to buy the company for $2.2 billion, with minority equity financing from Huawei Technologies.

It also reported pending applications for 35 separate inventions outside of China covering a wide range of networking technologies.

3Com came close to merging with computer maker Convergent Technologies, abandoning the pact just two days before a vote was scheduled in March 1986.

CommWorks was formerly the Carrier Network Business unit of 3Com, comprising several acquired companies: U.S. Robotics (Rolling Meadows, Illinois),[18] Call Technologies (Reston, Virginia),[19] and LANsource (Toronto, Ontario, Canada).

U.S. Robotics provided media gateways (the Total Control 1000 product line, formerly used for dial-modem termination) and softswitch technology.

The Carrier Network Business unit of 3Com developed an Inter-working function technology that became the first and dominant 2G CDMA wireless data gateway product.

[21] This product was deployed in the United States, Japan,[22] and Korea covering the 2G CDMA market sample carriers included Sprint.