Future Internet

This paper was written in 1994, and is quite insightful in that it predicts the rise of real-time video and audio links across the internet. The paper attempts to provide design decisions for the future of the internet. In particular, it suggests that there be multiple tiers of service within the internet, and that higher tiers should be explicitly requested by applications. The final suggestion is that there be admission control (i.e. the internet should reject some flows) to increase the quality of service for currently existing flows.

There are so many problems here, I don't even know where to begin. The suggestion of multiple tiers of service within the internet is a fine suggestion (because, in fact, real-time applications have very different needs when compared to applications such as FTP). Furthermore, the suggestion that the distinction be done above the IP layer (perhaps at the protocol layer) is also a good suggestion, because it allows the IP layer to serve its current purpose without taking on an unrelated purpose.

The suggestion that applications should explicitly request better service, while seemingly logical at first, creates a lot of difficulties in practice. The largest problem to be faced here is the problem of incentives. If there is no incentive to request the lower quality of service, everybody will request the higher quality of service. If the incentive is, as the paper suggests, monetary, then this will create additional problems. Nevermind the fact that people generally prefer to be billed a flat rate for unlimited internet access; if a remote host starts a high QoS TCP connection to an unsuspecting victim, will he be charged for the ACKs that he sends back? As another example, it would seem impossible for a server to declare that it wanted to stream videos to users at a high QoS, while still allowing users to "opt out" of the high QoS based on financial considerations. In general, connections between different nodes that requests different QoS levels will be tricky as a whole.

The admission control suggestion seems to be more applicable to traditional telephone conversations than it is to the internet. As far as the internet is concerned, everything is a packet, and there are no flows. Rejecting one flow so that another has a higher QoS would be very difficult to do on a router that is situated between two endpoints for several reasons: 1) the router may not see all of the traffic of that flow, making it difficult to reject the whole flow and 2) keeping track of which flows need high QoS and rejecting other flows because of it would entail large amounts of state within the router. The idea of rejecting flows so that others can have higher QoS is even more ridiculous when we consider where the responsibility should fall. Can it be done by any router? Can it be done by all ASs or just Tier 1 service providers? Who can decide which flows are more important than others? These issues will plague the idea of admission control if anybody ever tries to implement it.

I am even more surprised that this paper doesn't have a large focus on authentication. One of the largest issues of the modern internet is that in general, it is easy to spoof your own identity. If this issue could be solved, it would lead to great improvements in the internet from fairer routing to simpler authentication methods/interfaces. This issue is not considered very much in this paper. I am very disappointed with the paper's general lack of foresight.