The middle layer provides services for distributed computing, things such as security, management, information flow control, location and naming services. The third layer is the foundation layer in which you find the basic network communication protocols and the environment where the application executes. Most of the technology already exists. What's missing is consistent deployment and infrastructure support. There are cryptographic algorithms that work just fine.
Management is a similar story.
People are starting to realize that having a consistent management framework is important. As more technology gets deployed, we don't all want to turn into network administrators. Agents are one possible approach to management, but there are others. You already find Hewlett-Packard Co. and IBM Tivoli Systems Inc. putting out management applications that have a great deal of visibility into what they manage. Those applications don't use agent technology.