When using MOC, OCS, Lync or Skype for Business as the corporate communication device for IM and presence in combination with a UC infrastructure from Cisco for voice, video and Extension Mobility, the status of the IM&P client does not get updated after a status change of the associated desk phone. Therefore the status of the user may not be available by legacy desk phones if the user logs off or logs on using Extension Mobility.

By using ALM this problem does not longer exist, because ALM will maintain a link with the EM status of the user and the presence status of the Microsoft IM&P client. Therefore the user status is always accurate and never out of sync.