The current document summarizes the experiences obtained during the ma
intenance and operations of the cache hierarchy within the German broa
dband research network. Installed at central nodes, the cache service
is an integral part of the backbone infrastructure. Ten distributed ca
che servers are the building blocks of a large scale top-level cache h
ierarchy. Since the beginning in January 1997, the DFN cache service w
as subjected to different mesh designs and conceptions. Various approa
ches were aimed at improvements in the load and traffic balance among
the caches. At the same time, the benefit of the mesh as whole was to
be increased, as well. Due to the fact that the caches are used in a p
roduction-like environment, few of the variations thought of manifeste
d themselves in practical configurations. Maintainers of similar cache
meshes may benefit from our ideas and experiences related in this doc
ument for their own conceptual design, configuration, and hardware sel
ection. The reader might want to investigate further publications desc
ribing the design of single web caching systems [1-4]. (C) 1998 Elsevi
er Science B.V. All rights reserved.