Sub-Wave Network
The subwave network is a piece of sentient software programmed to find anyone who could help to contact the Doctor. It uses a subwave to transmit, which means it is undetectable as it is below normal waves. It was created by the Mr Copper Foundation and further developed by Harriet Jones.
When the New Dalek Empire transported twenty-seven planets to the Medusa Cascade, including the Earth, in 2009. Harriet Jones activated the network when the United Nations surrendered on Earth's behalf. The network found Jack Harkness at the Torchwood Hub, Sarah Jane Smith at 13 Bannerman Road and Martha Jones at her mum's house. It also found Rose Tyler at Donna Noble's house but se was unable to communicate with anyone since the laptop she was using didn't have a webcam.
The Children of Time moving against the Daleks
Jack Harkness: Wait a minute. We boost the signal, that's it. We transmit that telephone number through Torchwood itself, using all the power of the rift.
Luke Smith: And we've got Mr Smith. He can link up with every telephone exchange on the Earth. He can get the whole world to call the same number at the same time. Billions of phones calling out at once.
Harriet Jones: Now enough of words, let's begin.
Ianto Jones: Grid power activated.
Gwen Cooper: All terminals co-ordinated.
Ianto Jones: National Grid online, giving you everything we've got.
Sarah Jane Smith: Connecting you to Mr Smith.
Luke Smith: All telephone networks combined.
Martha Jones: Sending you the number now.
Harriet Jones: Opening subwave network to maximum.
Sarah Jane: Mr Smith, make that call.
Mr Smith: Calling the Doctor.
Jack: And sending!
