Building Internet Firewalls, 2nd Edition

Colophon

Our look is the result of reader comments, our own experimentation, and feedback from distribution channels. Distinctive covers complement our distinctive approach to technical topics, breathing personality and life into potentially dry subjects.

The illustration on the cover of Building Internet Firewalls is of a doorway of Gothic design, topped by a crenelated parapet. The period of Gothic architecture is often said to have begun in the mid-12th century, when the church of Saint-Denis was built, in Paris in 1144. The architect of that church is unknown. Although Gothic architecture was mainly used in the building of churches, by the late 13th century it was used for secular purposes also, including fortifications. The structure of the merlons (the raised portions of the parapet) in this illustration gives information about the date and place of construction. The oblique sides of the merlons suggest that the doorway was built in the 14th century, and the plain but sloping top suggests that it was built in England or France.

Merlons were designed to provide defense to those inside the fortification, while crenels (the recessed portions between the merlons) let them shoot projectiles at attacking enemies. Given the size of this door, and the relatively low merlons, this may have been a postern, a doorway used by foot travellers to avoid lowering the main gate.

Madeleine Newell was the production coordinator for this book. Nancy Crumpton provided all editorial and production ...