Revisit the Internet architecture as introduced in Chapter 3. What impact does the introduction of overlay networks have on this architecture, and in particular on the programmer’s conceptual view of the Internet?

Question

What will be an ideal response?

Answer 1

The initial Internet architecture was devised for a relatively small number of applications (such as electronic
mail and file transfer) to run over relatively homogeneous styles of network. The definition and standardization
of the (relatively simple) Internet architecture has been very successful in supporting these applications and
other emerging applications. As the Internet grows though in terms of scale and diversity, there is a need to
support richer application styles and also to operate more effectively over an increasing variety of network
types. The introduction of overlay networks introduces an element of extra complexity into the Internet
architecture but also an increasing degree of sophistication to meet these two requirements. For example,
overlay networks can be introduced to support new styles of Internet applications, for example related to
streaming of continuous media content. The Internet can also be extended to operate more optimally over new
network types, for example ad hoc networks.
The key elements in terms of the conceptual view offered by the Internet is that programmers now see
the architecture as extensible and also see the potential to have more application-specific network services.
They also see a move from rigid standardization to a more experimental environment.