Stream Scanning For Content Filtering - NETGEAR STM150 - ProSecure Web And Email Threat Management Appliance Reference Manual

- Up to 239 MB/s HTTP throughput
- Up to 960,000 emails per hour SMTP throughput
• Stream Scanning technology that enables scanning of real-time protocols such as HTTP.
• Comprehensive Web and email inbound and outbound security, covering six major
network protocols: HTTP, HTTPS, FTP, SMTP, POP3, and IMAP.
• URL content filtering with 64 categories.
• Malware database containing hundreds of thousands of signatures of spyware, viruses,
and other malware threats.
• Very frequently updated malware signatures, hourly if required. The STM can
automatically check for new malware signatures as frequently as every 15 minutes.
• Multiple antispam technologies to provide extensive protection against unwanted emails.
• Spam and malware quarantine for easy analysis.
• Web application control, including access control for instant messaging, media
applications, peer-to-peer applications, and Web-based tools and toolbars.
• User management with LDAP, Active Directory, and RADIUS integration, allowing you to
configure access policies per user and per group.
• Easy, Web-based wizard setup for installation and management.
• SNMP-manageable.
• Dedicated management interface. (This feature is model dependent; see
Comparison on page 12.)
• Hardware bypass port to prevent network disruption in case of failure. (This feature is
model dependent; see
• Front panel LEDs for easy monitoring of status and activity.
• Internal universal switching power supply.

Stream Scanning for Content Filtering

Stream Scanning is based on the simple observation that network traffic travels in streams.
The STM scan engine starts receiving and analyzing traffic as the stream enters the network.
As soon as a number of bytes are available, scanning starts. The scan engine continues to
scan more bytes as they become available, while at the same time another thread starts to
deliver the bytes that have been scanned.
This multithreaded approach, in which the receiving, scanning, and delivering processes
occur concurrently, ensures that network performance remains unimpeded. The result is file
scanning that is up to five times faster than with traditional antivirus solutions—a performance
advantage that you will notice.
Stream Scanning also enables organizations to withstand massive spikes in traffic, as in the
event of a malware outbreak. The scan engine has the following capabilities:
• Real-time protection. The Stream Scanning technology enables scanning of previously
undefended real-time protocols, such as HTTP. Network activities susceptible to latency
(for example, Web browsing) are no longer brought to a standstill.
10 | Chapter 1. Introduction
ProSecure Web/Email Security Threat Management (STM) Appliance
STM Model Comparison on page 12.)
STM Model