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MailDefender network level control of Spam and Viruses


Business Problem:


Most e-mail is Spam! Most viruses come through e-mail! The MailDefender appliance filters out unwanted email and viruses at the firewall level. MailDefender will protect the integrity of your corporate email system and network itself, by preventing dangerous penetrations and subsequent time-consuming responses to such incidents.


Firewall-Level Filtering:


With the MailDefender gateway appliance or hosted service, you add another layer of physical security at your firewall level or in your DMZ (Demilitarized Zone). Most organizations have anti-virus on their desktops and mail servers. This gives you anti-virus at a third-level, the perimeter of your network. Trying to block spam at the mail server is not good enough. MailDefender leverages Linux and open-source tools and services so your total cost of ownership is much lower than commercial software vendors and other appliance providers.


Benefits:

  • Protects your organization from Viruses and Spam and employees from embarrassment and liability of offensive material

  • Increases employee productivity and system availability

  • Gives you a third layer of protections…at the firewall level

  • Buys back” network bandwidth, computing resources and staff time for productive use


Features:

  • Professional, Personalized Service and Support

  • User or Group based Policy-based filtering with web-based administration

  • Mail filtering based in IP address checks, SMTP envelops, headers and text of the message body. Eliminates spam, porn and other junk email

  • Virus-filtering of SMTP traffic

  • Real-time checks of known spam offenders and new viruses updates every 10 minutes from (3) sources are made to the mailDefender database

  • Configurable, scalable platforms to fit your exact requirements, Load-sharing with multiple appliances.

  • MailDefender is offered as a Managed or Hosted Service, so you do not have to administer the operating system, application software, databases and backups, or even monitor the operation of the appliance. xDefenders does that for you!

  • Extensive Reporting and Diagnositic Tools


Description:


Typically, MailDefender will be installed in your DMZ (or as a hosted service) and accepts all inbound and outbound Port 25 mail traffic. After inspection, it will route acceptable mail to your corporate internal mail system for final delivery.


It will filter out unwanted mail and forward acceptable mail, based on IP addresses of know spam senders, SMTP envelope, header and keyword checks. Confirmed SPAM mail will be deleted or routed to an administrators mailbox, which allows the suspected spam messages to be examined before deletion. Spam can be labeled as such and delivered to the intended recipient. You have the ability to override these automatic updates by “white-listing”. Advanced, content filtering is performed by Spam-Assassin, a proven heuristic assessment tool, that you can regulate.


MailDefender has a built-in Anti-Virus application to inspect mail messages and attachments. It will quarantine every email with a virus for manual inspection. An email will be sent to the offending sender indicating that they are sending viruses and an email will be sent to the intended recipient that a virus filled email arrived. The MailDefender database will be automatically updated every 10 minutes, from 3 different sources, so that inspection is timely and current.


The MailDefender appliance is offered in small, medium, large and redundant configurations, to accommodate any size business need.


Technical Features:

  • GreyListing – qualifies mail to be valid before acceptance

  • User Validation - Supports Active Directory (LDAP) integration to prevent Dictionary Attacks

  • RBL and Heuristic - Advanced Text Assessment Techniques

  • Fail-over configuration using “Round Robin” technique

  • Denial of Service Prevention, Intrusion Detection sensor optional

  • Web-Based Administration Interface

  • Complete Reports Package, Diagnostic Tools

  • Encrypted SMTP optional, per domain, Supports multiple Domains


Filtering Process

  • Internal and External e-mails arrive at port 25 (SMTP)

  • Greylisting may be applied forcing a re-send from a valid sending server, if sender has not sent before a 35 day period

  • Valid User Directories are checked to prevent Dictionary Attacks

  • Mail:From address is being checked against a two, conservative Real-time Black-hole Lists. If found there, the IP connection is severed. Transaction logged. Most spam blocking occurs here.

  • Mail:From address is checked for known spam senders. If found there, email is rejected with an error message back to the sender and an entry in the log.

  • e-mail body is being checked for specific regular expressions that clearly classify the email as Spam. If detected, email is rejected with an error message back to the sender and an entry in the log

  • All e-mail headers are being checked for specific regular expressions clearly classify the email as Spam. If detected, email is rejected with an error message back to the sender and an entry in the log e-mail is deposited into a queue

  • If e-mail has progressed this far, it is pulled from the queue and checked for Spam using a dual-level scorng system. If Spam score reaches or exceeds set thresholds (user controlled), e-mail is tagged as Spam and either sent to the original recipient or re-directed to a specific mailbox (user defined process) or deleted outright.

  • e-mail is being checked for viruses. If detected, email is being quarantined on the server along with a message back to the sender and a message to the system administrator (user defined process)

  • Optional Mail Archiving (clean mail) can take place, at this time.


MailDefender Features - Business


Hardware Appliance(s) Small, medium and large, HP servers

Managed and Hosted Services, by xDefenders, also Hosted in SAS 70 data center with redundancy

High Availability Configurations, via Load Sharing

Remote Backup, Remote Monitoring

OS, Applications and DB updates

User Controls & Options

Web-based Administration 

Remote Control & Reboot 

Real-Time Monitoring w/ Alerts 

Disaster Recovery Method Simple CD re-load, 1 hour

Hardware Maintenance Plan Next Day Overnight Replacement

Remote Backups Made Weekend nights @ xDefenders HQ

New Software Uploads Quarterly

Reports Package Yes, Daily, Weekly, Monthly, Annual

Graphical Reports

Mail Server Optional, Post Fix implementation

Mail Archive Optional, software or appliance


MailDefender FeaturesTechnical


Firewall, Gateway appliance

Protocol Filtered SMTP

Viruses Filtered SMTP

Firewall Built-in for extra Security

Operating System Hardened Linux

OS Reliability Best of Breed

Applications (3) Real-time Black-hole Lists

Spam Assassin Scoring Filter

FPROT, BDC and Clam AV’s

Post-Fix Mail Transport

GreyListing Optional

Advanced Rule Base Filtering Heuristic Algorithms

Anti-Virus Pattern Updates Every Ten Minutes

Blacklist updates Hourly

White Listing/ Overrides

Attachment Controls (ActX, Java) 

MIME De-fang

Multi-Language Support (French, Port.

MS MMC Snap-In Support

LDAP Support to block Dictionary Attacks by checking first for valid users

Secure Web Mail

Encryption, by default

POP3, IMAP4 Filtering Optional

User or Group Set Policy

Reporting Extensive

Diagnostic Tools for eMail


MailDefender - Managed and Hosted Services include:

  • Appliance - Design, Deploy, Manage, Monitor, Maintain

  • Hardware and software and services

  • Pre-Installed Linux Configuration

  • Turnkey Installation and basic fine-tuning of rules

  • Escalation Plan Developed with I/T Staff.

  • Online Documentation, Web Interface

  • Technical phone and email support

  • Databases updated, automatically (daily, AV is every 10 minutes)

  • Secure SSH connection to/from xDefenders Security Operations Center

  • OS and Applications patched, enhanced, remotely

  • Weekly local and remote backups

  • Hardware maintenance is next day overnight, replacement

  • Typical HP appliance has dual core Intel, 2 GB ram, CD, 200 GB disk.

  • Appliance has a 1 Year Warranty from date of shipment

  • SAS 70 Data Center with Redundancy