Managed Anti-Spam
The Network Box Anti-Spam solution is the most comprehensive and effective gateway Anti-Spam solution in the market today. It provides 25 Anti-Spam engines, combining over a dozen different techniques and is backed by a vast database of Anti-Spam signatures. It provides true defence-in-depth, in a single managed gateway appliance.
The Network Box Anti Spam email gateway achieves an industry-record 97.5% detection rate, with almost zero-false-positives.
Some of the solutions deployed by Network Box are:
- Co-operative Spam Checksums
This technique involves breaking apart a message and taking cryptographic checksums of each component of the message. - Signatures and Spam Scoring
Lists of ‘signatures’ which match aspects of spam messages. - White lists and Black lists
A list of words / patterns which make a message ‘ham’ (good email) or ‘Spam’. - Heuristics
By examining behaviour, tests can be designed to determine if an e-mail is Spam. - Real-Time IP Blacklists
Lists of gateways known to be either:- known sources of Spam
- known open-relays (allowing third-party relaying of messages)
- known dial-up networks
- Real-Time URL Blacklists
Lists of URLs used by spammers - URL to IP Mapping and Blacklists
Lists of IP addresses used by spammers - URL Categorisation
Using the on-board SurfControl database, URLs can be categorised - Domain Age
If a domain is very young this can be an indicator of Spam. - Bayesian Filtering
Statistical (or Bayesian) filters can be used to automatically maintain word / pattern white lists and blacklists, together with statistical probabilities as to whether the given word / pattern makes the message spam / ham. - Challenge / Response Systems
Network Box can challenge previously unknown senders to check they are not spammers. - Digital Signatures
This technique is normally used to indicate that an email message is ‘ham’ and is not used to determine spam. - Optical Character Recognition (OCR)
Spam sent as pictures can be interpreted as text and hence detected.
Anti-Spam Configuration
The Network Box email system is extremely configurable. Individual engines can be enabled or disabled based on tests, including:
- Direction of the message (inbound or outbound)
- Whether the message is being filtered (eg, POP3, IMAP4)
- Whether the message is redirectable (eg, SMTP)
- Globally (ie, for everything)
- Based on the content of a message headers
- Based on the proxy handling the message (eg, SMTP, POP3)
- Based on a single recipient of the message
- Based on a recipient being one of the recipients of the message
- Based on the sender of the messages
- Based on the sender IP address
- Individual engine parameters can be set to adjust scores and weightings to suit end-user requirements.
