The session layer has been neglected for too long. This neglect has led to applications implementing pieces of the session layer themselves. Errors in authentication and encryption code continue to cause security issues is networked applications. VPNs, firewalls, IPSec, virtual hosting, port knocking and even port numbers are all examples of technology where a well-implemented session layer could potentially provide forward progress against the status quo. In addition, a session layer can also provide improvements the modern Internet lacks, such as better support for mobility, connection bonding and other various features.
Image 1: Fived in action
Fived is a daemon and client which expose a service-oriented networking system. This experimental daemon is currently our framework for experimenting with the viability, design ramifications and potential uses of a session layer on the modern Internet. While the daemon grew out of a 20 year RFC specifying the tcpmux protocol, it's moved forward by leaps and bounds to expose all kinds of interesting opportunities. We think this work has potential to create overlays that will solve a wide range of problems coming to a head on the Internet and the time seems right for change.