With over 90% of cyberattacks initiated by email, every harmful message detected counts for innovative security service provider Censornet. By integrating Spamhaus’ real time blocklists and enabling two-way sharing of basic email connection data, Censornet has enhanced email protection and accuracy for its users… to exceptional levels. Read on to learn more.


Getting to know Censornet

With a mission to protect and serve mid-size enterprises, Censornet safeguards millions of users across the globe, processing over a billion security events per day. Today, over 2,500 organizations worldwide rely on Censornet for autonomous integrated cloud security, to fortify their cyber defences. Using a unique set of technologies and strategic machine learning, Censornet’s security platform stops threats that enter an organisation by email, over the web, or from the cloud.

Enterprise-grade email security for mid-tiers

For Censornet, Email Security (EMS) is a linchpin in their cyber security offering. Integrating multiple traditional and ultra-modern approaches, the Email Security solution ensures enterprise-class threat detection rates with exceptional accuracy. By taking this multi-layered approach, the EMS solution holistically defends against traditional threats such as spam, viruses and large-scale phishing, as well as more sophisticated targeted attacks, impersonation fraud and malware.

Email traffic passes through Censornet’s EMS, where it completes a multi-step email filtering process. First, the email is analysed against threat intelligence data, including Spamhaus’ real-time DNS blocklists (DNSBLs) – accessed via the Data Query Service (DQS). The DNSBLs remove any obvious spam sent from known botnets and spammers, dropping a significant amount of bad email traffic before processing or analysis.

The remaining email traffic passes through anti-virus/anti-spam technology and a set of customer-defined rules before the clean mail is delivered to the customer’s server. Any detected harmful email is immediately quarantined or dropped.

By integrating Spamhaus’ DNSBLs, Censornet prevents over 99% of malicious emails from reaching users’ mailboxes. This instantly recovers bandwidth, servers and storage costs typically lost when accepting and processing spam. Furthermore, Richard Walters, CTO, shared: “Our infrastructure scales significantly better now we are dropping a significant amount of bad email traffic before we take it apart and analyze it.

Every email counts for exceptional protection

For Censornet, the focus lies not only in providing an overall level of exceptionally high email security protection but also in ensuring accuracy. By blocking over 99.999% of spam emails, at this point, the game is all about tiny margins. Minuscule incremental improvements, where every 100 detected harmful email messages make a difference. Richard, explained, “If we manage to incrementally halt thousands of email messages every month, above and beyond what we were already stopping, it speaks volumes.

Targeted protection for Censornet users

As a long-standing subscriber to Spamhaus’ DNSBLs, Censornet wanted to do more. They wanted targeted accuracy. At Spamhaus we call this ‘Enhanced Protection’.

By sharing their basic email connection data with Spamhaus, we can detect spammers and threats from patterns in data from Censornet’s users email streams, all without requiring any personally identifiable information (PII). Where malicious or suspicious activity is detected, the IP addresses and domains are added to Spamhaus data sets feeding back directly into Censornet’s EMS solution to block any harmful incoming email.

Keep in mind, not everybody receives the same spam, phishing, or malware emails. Censornet will receive traffic unique to their organization, geography, and industry. They may also detect malicious traffic before others. In both cases, sharing this sort of traffic with Spamhaus improves our data performance for Censornet – and for other users as well.

With Enhanced Protection, Censornet shares basic email connection data and in return accesses additional security against malicious emails specifically targeted at its users, and they are pleased with the results. In Richard’s words:After 30 days, we received a report showing precisely what incremental value and the incremental protection the data exchange had provided.

Increasing efficiency at every level

Sharing SMTP connection data with Spamhaus has yielded a multitude of benefits for Censornet. First and foremost, it provides targeted accuracy to their EMS solution, ensuring a higher level of security for users. To bang the drum, every harmful email message counts! Consequently, this allows Censornet to offset infrastructure costs, enabling expansion through adding more users to the existing infrastructure.

The advantages don’t stop there; there are indirect benefits too. Improved customer satisfaction is a natural outcome. Richard proudly shared: “Delivering a service with exceptionally high levels of protection and accuracy, we don’t see customer churn. Our net renewal rate annually is over 115%, which is pretty world class for a provider of SaaS solutions.

He continued, “Furthermore, the accuracy of the solution has translated to fewer support calls, reducing the burden on the support and customer success teams.

Setting the standard for email security

Even the athletes of email security seek enhanced performance. With Spamhaus’ industry leading DNSBLs and two-way sharing of basic email connection data, Censornet continues to strive for incremental advances to its security solution. And according to Richard, Censornet achieves this by strategically selecting and aligning with trusted and authoritative partners: “We wouldn’t dream of building a service without Spamhaus – we absolutely trust the tech, we love the data, more specifically the quality.

United by a shared passion to safeguard users’ mailboxes worldwide, Spamhaus is inspired by Censornet’s commitment to providing exceptionally high email security protection. To learn more about Spamhaus’ Enhanced Protection, please contact us here.

Data Query Service (DQS)

Spamhaus’ Data Query Service (DQS) is an affordable and effective solution to protect your email infrastructure and users.

Using your existing email protection solution, you will be able to block spam and other related threats including malware, ransomware, and phishing emails.

The service has never failed and utilizes the longest established DNSBLs in the industry.

  • Proactive & preventative
  • Save on email infrastructure & management costs
  • Actionable

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