Cyber-network
The Cyber network was the network that linked every Cyberman to one another. It contained their database and was used transfer files wirelessly. (TV: Rise of the Cybermen/The Age of Steel) It could also receive information from infostamps, giving Cybermen a means of exchanging information when their wireless systems were inactive. (TV: The Next Doctor)
To defeat the reviving ship of Cybermen that crashed in Klimtenburg, the Eleventh Doctor cut off a partially-converted Victor Ernhardt from the Cyber-network. Victor's Cyber body was then charged with with excess power from a lightning stike so when he was reconnected to the network, the other Cybermen overloaded and died. (PROSE: Plague of the Cybermen)