The Network Coding Home
Welcome to the Network Coding Coding Home Page.
This site is meant to provide a service to the community by
main developments in network coding.
Like many fundamental concepts, network coding is based on
a simple basic idea which was first stated in its beautiful simplicity
in the the seminal paper by R.
Ahlswede, N. Cai, S.-Y. R. Li, and R. W. Yeung, "Network Information
Flow", (IEEE Transactions on Information Theory, IT-46, pp.
1204-1216, 2000). The core notion of network coding
is to allow and encourage mixing of data at intermediate network nodes.
A receiver sees these data packets and deduces
from them the messages that were originally intended for the data
sink. In contrast to traditional ways to operate a network that
try to avoid collisions of data streams as much as possible, this
elegant principle implies a plethora of surprising results. One of the
most exciting opportunities of the approach is the use of random mixing
of data streams, thus freeing up the symmetrizing properties of random
coding arguments in the analysis of networks. Not only is network
coding a fresh and sharp tool that has the potential to open up
stagnant fundamental areas of research, but due to its cross-cutting
nature it naturally suggests a unified treatment of previously
segmented areas. A striking example of the type of
unification that network coding makes possible is the recently found
and complete characterization of the capacity of multicast networks,
was possible only through the joint treatment of coding and
Our hope is that this site can serve as a repository and resource for
researchers and scientists in the field
The principle of network coding is easiest explained with an example (from Ahlswede et
al.). In this example two sources having access to bits A and B
at a rate of one bit per unit time have to communicate these bits to
two sinks so that both sinks receive both bits per unit time. All links
have a capacity of one bit per unit time. The network problem can be
satisfied with the transmissions outlined in the example but cannot be
satisfied with only forwarding of bits at intermediate packet nodes.
(If you want any information included in these links send me an email
"This material is based upon work supported by the
National Science Foundation under Grant No. CCR-0325673"
"Any opinions, findings and conclusions or recomendations expressed in
this material are those of the author(s) and do not necessarily reflect
the views of the National Science Foundation (NSF)."
Last updated: 10/29/2003