An RHN Proxy Server is a service deployed within a corporate network with advanced Red Hat Network functionality, such as a package-caching mechanism for reduced bandwidth usage and customizable channels enabling custom package deployment.
This service allows a business or corporation to cache RPM Updates on an internal, centrally located RHN Proxy Server and have the client systems download the updates from that server instead of from one of the RHN Servers  over the Internet. The clients' System Profiles and user information are stored on the secure, central RHN Servers, which also serve the RHN website (rhn.redhat.com). The Proxy does not serve the website itself; It acts as a go-between for client systems and Red Hat Network. Only the RPM files are stored on the RHN Proxy Server. Every transaction is authenticated, and the Red Hat Update Agent checks the GPG signature of each package retrieved from the local RHN Proxy Server.
In addition to storing official Red Hat packages, the RHN Proxy Server can be configured to deliver an organization's own custom RPM packages from private RHN channels, using the RHN Package Manager. For instance, an organization could develop its own software, package it in an RPM, sign it with its own GPG signature, and have the local RHN Proxy Server update all the individual systems in the network with the latest versions of the custom software.
Advantages of using RHN Proxy Server include:
Scalability — there can be multiple local RHN Proxy Servers within one organization.
Security — an end-to-end secure connection is maintained: from the client systems, to the local RHN Proxy Server, to the Red Hat Network Servers.
Saves time — packages are delivered significantly faster over a local area network than the Internet.
Saves bandwidth — packages are downloaded from the RHN File Servers only once (per local Proxy Server's caching mechanism) instead of downloading each package to each client system.
Saves disk space on individual systems — one large disk array is required instead of extra disk space on all the client systems.
Customized updates — create a truly automated package delivery system for custom software packages, as well as official Red Hat packages required for the client systems. Custom private RHN channels allow an organization to automate delivery of in-house packages.
Customized configuration — restrict or grant updates to specific architectures and OS versions.
Only one Internet connection required — the client systems connect through the HTTP-enabled Proxy Server and do not need an Internet connection. Only the RHN Proxy Server needs an Internet connection to contact the RHN Servers.
Throughout this document, replace RHN Server with RHN Satellite Server if the RHN Proxy Server connects to a RHN Satellite Server instead.