[11] The Blue Box used circuitry made by Andy Bechtolsheim, and software that was originally written at Stanford by research engineer William Yeager.

On July 11, 1986, Bosack and Lougheed were forced to resign from Stanford and the university contemplated filing criminal complaints against Cisco and its founders for the theft of its software, hardware designs, and other intellectual properties.

[11] In addition to Bosack, Lerner, Lougheed, Greg Satz (a programmer), and Richard Troiano (who handled sales), completed the early Cisco team.

[18] Classical, CPU-based architecture of early Cisco devices coupled with flexibility of operating system IOS allowed for keeping up with evolving technology needs by means of frequent software upgrades.

[19] Between 1992 and 1994, Cisco acquired several companies in Ethernet switching, such as Kalpana,[20] Grand Junction[21] and most notably, Mario Mazzola's Crescendo Communications,[22] which together formed the Catalyst business unit.

This resulted in a new ASR 9000 product family intended to consolidate the company's carrier Ethernet and subscriber management business around EZChip-based hardware and IOS-XR.

Cisco placed the Reactivity team and product portfolio under its Datacenter Switching and Security Technology Group, which reported to the company's then senior vice president Jayshree Ullal.

[40] At the end of 2013, Cisco announced poor revenue due to depressed sales in emerging markets, caused by economic uncertainty and by fears of the National Security Agency planting backdoors in its products.

[47] On November 19, 2015, Cisco, alongside ARM Holdings, Dell, Intel, Microsoft and Princeton University, founded the OpenFog Consortium, to promote interests and development in fog computing.

[48] In January 2016, Cisco invested in VeloCloud, a software-defined WAN (SD-WAN) start-up with a cloud offering for configuring and optimizing branch office networks.

In April 2023, it became known that the company had destroyed equipment, spare parts, and even vehicles and office furniture worth 1.86 billion rubles (about $23 million) due to the impossibility of re-exporting.

[70] On 15 February 2024, Cisco announced it would lay off more than 4,000 employees, or 5% of its global workforce, and lowered its annual revenue forecast due to economic challenges and reduced demand from telecom and cable service providers.

[98] In 1999, Cisco also acquired a stake for $1 billion in KPMG Consulting to enable establishing Internet firm Metrius founded by Keyur Patel of Fuse.

[99] Several acquired companies have grown into $1Bn+ business units for Cisco, including LAN switching, Enterprise Voice over Internet Protocol (VOIP) platform Webex and home networking.

[112] For instance, in 2010 Cisco occupied a meaningful share of the packet-optical market,[113] revenues were still not on par with US$7 billion price tag paid in 1999 for Cerent.

[118] In January 2013, Cisco Systems acquired Israeli software maker Intucell for around $475 million in cash, a move to expand its mobile network management offerings.

[123] On June 16, 2014, Cisco announced that it has completed the acquisition of ThreatGRID, a company that provided dynamic malware analysis and threat intelligence technology.

The deal will give Cisco Embrane's software platform, which provides layer 3–7 network services for things such as firewalls, VPN termination, server load balancers and SSL offload.

[127] On May 7, 2015, Cisco announced plans to buy Tropo,[128] a cloud API platform that simplifies the addition of real-time communications and collaboration capabilities within applications.

[129] On June 30, 2015, Cisco acquired privately held OpenDNS, the company best known for its DNS service that adds a level of security by monitoring domain name requests.

[130] On August 6, 2015, Cisco announced that it has completed the acquisition of privately held MaintenanceNet, the US-based company best known for its cloud-based contract management platform ServiceExchange.

[131] On the same month, Cisco acquired Pawaa, a privately held company in Bangalore, India that provides secure on-premises and cloud-based file-sharing software.

[132] On September 30, 2015, Cisco announced its intent to acquire privately held Portcullis Computer Security, a UK-based company that provides cybersecurity services to enterprise clients and the government sectors.

[135] On June 28, 2016, Cisco announced its intent to acquire CloudLock, a privately held cloud security company founded in 2011 by three Israeli military veterans,[136] for $293 million.

[170] Cisco became a major provider of Voice over IP to enterprises and is now moving into the home user market through its acquisitions of Scientific Atlanta and Linksys.

[185] Cisco was a 2002–03 recipient of the Ron Brown Award,[186][187] a U.S. presidential honor to recognize companies "for the exemplary quality of their relationships with employees and communities".

[203] Wired News had uncovered a purported leaked, confidential PowerPoint presentation from Cisco that detailed the commercial opportunities of the Golden Shield Project of Internet control.

In May 2010, Cisco accused the person who filed the antitrust suit, British-Nigerian technology entrepreneur Peter Alfred-Adekeye, with hacking and pressured the US government to extradite him from Canada.

These Trojan horse systems were described by an NSA manager as being "some of the most productive operations in TAO because they pre-position access points into hard target networks around the world.

[234] In 2020, a lawsuit was initiated against Cisco and two of its employees by the California Department of Fair Employment and Housing for alleged discrimination against an Indian engineer on account of him being from a lower caste than them.