Active Network

This paper talks about Active Network. Active networks allows per packet specific processing and embed the processing inside of packet using the concept of a capsule. This gives the network the flexibility to adapt to different need quickly and allows rapid deployment of new protocols.

The main problem that I see and author recognize in this setting is security and performance. To address security, they are using a restricted subset of Java. However, I don't think they are considering the problem of resource exhaustion. Of course, they have a certificate based solution as back up. However, that is very heavy weight, and usually the root trust has to be traced to one entity. I doubt all the networks in the world would trust a single entity to certify active code running in their networks. Subtle problems such as routing loops can occur simply because of a bug. Performance is also a critical issue. If the active content is not cached at the node, loading the node could introduce significant latency.

I like this paper in the curriculum because it introduces necessary background of active networks and gives some reflection on the experience of implementing such a toolkit.