The DOCSIS 1.1 CMTS, as defined by the CableLabs, is almost ready for PacketCable. This paper discusses the additional functionality that will be required by a CMTS in order to satisfy the requirements of the PacketCable specifications. Equally important, this paper also identifies and discusses the external back office elements that are required for a successful PacketCable deployment. This paper identifies the DOCSIS features that are used by PacketCable. Additional needs of telephony applications are identified, as well as an introduction to how these additional requirements are linked into DOCSIS features.