Real-time HTTP Scanning
avast! ISA Server Edition's most important job is the real-time scanning of all HTTP traffic. With today's boom of free webmails and other online hazardous content, HTTP scanning is becoming a real necessity. Thanks to a tight integration with the ISA Server itself, avast! is able to detect and remove viruses from all WWW pages/downloads. It does not matter how a client is downloading the infected program - be it using IE or any other browser, any 3rd party download acceleration tool or any other way - you can be confident that it will be properly screened and disinfected before it reaches the user. Of course, the scanning is not confined to programs - scripts, ActiveX objects and any other potentially hostile objects are monitored as well.
Special care has been taken to correctly handle even huge downloads (a typical problem of gateway-based AV solutions). avast! makes sure that scanning is performed properly even for these objects, still making sure that the client programs will not time-out waiting for a response from the proxy.
Real-time Scanning
Besides real-time HTTP scanning, avast! is able to filter FTP traffic as well.
FTP is still an important protocol for file transfers (i.e. downloads as well) and as such deserves almost as much attention as HTTP scanning. Thanks to the design of the CERN Proxy protocol (also known as the HTTP proxy protocol), avast! is able to transparently handle all FTP traffic using its HTTP filtering module.
High scalability
avast! Exchange Server Edition is easily deployable and works perfectly even on large datacenter servers and
cluster servers (including the active-active mode). The scanning engine was designed with two basic goals in mind:
performance and stability. It's able to take advantage of multiple CPUs, fully leveraging the potential of today's
advanced server hardware. Also, it supports scanning in memory (including the decompression of archives /
packed files), resulting in unrivaled scanning speed and robustness.
URL Blocking
avast!, ISA Server Edition also contains a simple URL blocker. You can specify URL masks (such as http://www.penthouse.com/* or *xxx*) of addresses that will be blocked from all access. This is a very simple yet extremely powerful way to prevent certain sites from being visited from the workspace.
Alerting & logging
As with any server-side software, it is very important to provide effective means of monitoring. For
these purposes, avast! offers a wide range of possibilities. These include thorough notification capabilities
via e-mail and avast's built-in Notification Manager (that supports a number of other transport protocols), rich
logging features, and performance counters.
The e-mail notifications are "intelligent" by means of predefined limits (to avoid flooding of the server with
avast's own messages) and also in the fact that they are only being sent to respective message senders if these
are really the originators of the infected mail (i.e. if the From: fields of the message have not been forged).
Automatic Updates
The ISA Server Edition uses identical updating modules as avast! Server Edition itself, resulting in unparalleled speed and size of updates. The updates can be either installed automatically by the updater, or manually. It is also possible to set the system up so that the updater first asks the administrator - prior to installing any updates.