Masqerading vs. Applikationproxy

[Waldemar Brodkorb <waldemar@thinknow.de>]

Hello *,

I have a question about firewall's and security on debian linux.

Is there an advantage to use application proxy's instead of a
masqerading box to secure a LAN with private IP addresses from
the dangerous internet.

I don't mean danger from inside the LAN (which could be solved
through user authentication, IP-based ACL's ...) 

When I have to allow users inside my network the use of IRC, ICQ, 
RealAudio/RealVideo or FTP (with a real FTP client), is then an 
application proxy more secure than masqerading?

Under application proxy's I understand the use of squid
(for http/ftp/https) or dante (for socks5 aware applications).

thanks for any comments in advance.

    bye
        Waldemar