German email provider, freenet, bring spam management in-house to increase control, flexibility and ultimately protection using Spamhaus' IP blocklists.

Client Profile

freenet, one of Germany’s major free email providers, supports customers across Austria, Switzerland and Germany, with around 4 million active users. Beyond email, freenet also deals in telecommunications and web content.

Bringing spam management in-house

In 2015, freenet, like so many, had a complete anti-spam service through an external provider. While this offered a simple solution, it meant their spam management was behind closed doors, with little transparency to adapt the approach to their business’ needs.

The team found themselves asking, ‘why do we accept some messages and reject others’ and ‘what is the implication of this to our service and protection of customers?’.

This lack of control and flexibility motivated the team to manage their own spam infrastructure, to appropriately protect their customers from malicious activity, without reliance on decisions made independently of their business.

Getting set up

Bringing spam management in-house meant building their own approach from the ground up. Most importantly, it needed to be multi-layered and dynamic. At the edge would be IP-based DNS blocklists (DNSBLs), well known for their ability to filter the vast majority of junk email at the gateway.

The freenet team chose Spamhaus’ blocklists as their reputation data of choice, evaluating them as the “gold standard”. Through Spamhaus’ partner, Security Zones, the DNSBLs were purchased and easily implemented. The data provided was in standard format with a straightforward interface to load in.

Benefits of in-house management with Spamhaus’ IP blocklists

Using IP blocklists which list over 10 million bad or suspect IPs, as their first line of defense at SMTP connect, freenet’s processing and storage requirements for content scanning are significantly reduced.

Lutz Harder from the freenet team shared that “[Spamhaus’] information is reliable, readily available and has proven to be a valuable asset allowing us to keep the cost for subsequent, more resource-intensive and time-consuming spam scanning at a much lower level.”

Moving to an in-house approach for spam management has also afforded freenet with flexibility around what mail they do or don’t accept, increased control of best practices and issue management, in addition to being responsible for their data’s privacy.

If you too are interested in other benefits to running your own email server, we list 6 advantages here.

Related products

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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