Active Network Vision and Reality: Lessons from a Capsule-Based System

Active networks allow individual user, or groups of users, to inject customized programs into the nodes of the network. This aids in building a range of applications that can leverage computation within the network. The authors in this paper use ANTS active network toolkit in designing and implementing active networks and share their experience.

The authors express their findings in comparison to the general vision of active networks in three areas:

1. Capsules: They can be a competitive forwarding mechanism whenever software-based routers are viable. Capsule code can be carried by reference and local on demand. The cost of capsule processing is not high when forwarding is also performed in software.
   
2. Accessibility: Each user can handle their packets within the network. Also, code from untrusted users should not do any harm to users of other service.
   
3. Applications: Capsules aid in experimenting with new services and deploying them.

The concept of active networks is new to me. The paper was good to read because it talked about the issues active networks have and how the authors experience these issues and resolve them. The only thing that concerns me is the issue that a malicious member of a group can harm other users of the group. The authors talk about this problem and also say that it is not specific to active networks.