* commit '2d258298e2fec670908c69e38c5a3a05b1f3d0f0': cherrypick Change-Id: I3c2a7ea731d2fc3c0e2372e2f1a06ed659a6539f docs: move the SIP guide into guide/network/
* commit '2d258298e2fec670908c69e38c5a3a05b1f3d0f0': cherrypick Change-Id: I3c2a7ea731d2fc3c0e2372e2f1a06ed659a6539f docs: move the SIP guide into guide/network/