Specifications

ident_lookup_access allow hacl_namei With this, you will manage to have

an ident request run through for all ACL-deﬁned clients to ﬁnd out

each user’s identity. If you apply all to the hacl_namei, this will be

valid for all clients. Also, an ident daemon must be running on all

clients. For Linux, install the pidentd package for this purpose. For

Windows, there is free software available to download from the Inter-

net. To ensure that only clients with a successful ident lookup are per-

mitted, a corresponding ACL will also have to be deﬁned here:

acl identhosts ident REQUIRED

http_access allow identhosts http_access deny all

Here, too, replace the REQUIRED with a list of permitted user names.

Using ident can slow down the access time quite a bit, because ident

lookups will deﬁnitely be repeated for each request.

Transparent Proxy Conﬁguration

The usual way of working with proxy servers is the following: the web

browser sends requests to a certain port in the proxy server and the proxy

provides these required objects, whether they are in its cache or not. When

working in a real network, several situations may arise:

For security reasons, it is recommended that all clients use a proxy to

surf the Internet.

All clients must use a proxy whether they are aware of it or not.

In larger networks already using a proxy, it is possible to spare yourself

the trouble of reconﬁguring each machine whenever changes are made

in the system.

In all these cases, a transparent proxy may be used. The principle is very

easy: the proxy intercepts and answers the requests of the web browser, so

that the web browser receives the requested pages without knowing where

they are coming from. This entire process is done transparently, hence the

name.

178 Transparent Proxy Conﬁguration