Arista Networks will pay Cisco $400m (£309m) in compensation to bring the legal war between the pair to a close.
The vendors have been locked in proceedings since 2014, when Cisco accused its rival of "repeated and pervasive copying of key inventions in Cisco products".
Arista had also launched a countersuit, claiming that Cisco was merely trying to snuff out a market rival.
A series of twists and turns have seen various instalments won by each vendor, but Arista has now conceded and agreed to pay Cisco to drop all the lawsuits.
In a regulatory filing Arista said: "Cisco will grant the company (Arista) a release for all claims of infringement with respect to the patent infringement allegations against the company in the pending litigation. The company will grant Cisco a release from all past anti-trust claims. These mutual releases will extend to the company's and Cisco's customers, contract manufacturers, and partners.
"The parties have further agreed to a five-year stand-down period as to any utility patent infringement claims either may have against features currently implemented in the other party's products and services, with some carve-outs for products stemming from acquired companies.
"The parties further agreed to a three-year dispute resolution process for allegations by either party against new and/or modified features in the other party's products."
Arista said the payment, along with $5m in legal expenses, will affect its current financial quarter, and now expects to report a net loss of $155.3m.
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