ARLINGTON, Va. — CAN we ever trust the Internet again?

In the wake of the disclosures about the National Security Agency’s surveillance programs, considerable attention has been focused on the agency’s collaboration with companies like Microsoft, Apple and Google, which according to leaked documents appear to have programmed “back door” encryption weaknesses into popular consumer products and services like Hotmail, iPhones and Android phones.

But while such vulnerabilities are worrisome, equally important — and because of their technical nature, far less widely understood — are the weaknesses that the N.S.A. seems to have built into the very infrastructure of the Internet. The agency’s “upstream collection” capabilities, programs with names like Fairview and Blarney, monitor Internet traffic as it passes through the guts of the system: the cables and routers and switches.

The concern is that even if consumer software companies like Microsoft and telecommunications companies like AT&T and Verizon stop cooperating with the N.S.A., your online security will remain compromised as long as the agency can still take advantage of weaknesses in the Internet itself.

Fortunately, there is something we can do: encourage the development of an “open hardware” movement — an extension of the open-source movement that has led to software products like the Mozilla browser and the Linux operating system.