For Internet Service Providers, it’s a constant battle to deliver the internet resources requested by the customer, but also keep them protected against malicious behaviour. CitraNET have managed to overcome this challenge with the flexibility offered by DNS Firewall Threat Feeds, resulting in a dramatic decrease in network abuse complaints.

Let’s get familiar with CitraNET

CitraNET is a local Indonesian Internet Service Provider (ISP) with over 20 years of experience serving corporate, residential, and public customers. In addition to providing connectivity via wireless and fiber optics, CitraNET also runs its own independent data center.

With so much experience, they are all too familiar with the quickly evolving threats that go hand-in-hand with the digital arena. Their approach focuses on constant innovation and finding reliable partners to support them in keeping their customers and network secure and protected.

The ISP security challenge

ISPs are the gateway to the biggest source of information – and subsequently abuse – on the planet. If users are inadvertently able to connect to malicious sites, become a botnet, or send unwanted traffic, it’s not just the user who is at risk. The ISP’s network, service and consequently their reputation are on the line too.

But putting protection in place for users isn’t all that straightforward. How do you stop customers from engaging with malicious sites, when ultimately that means blocking them from freely accessing information? ISPs can face serious litigation charges if they get it wrong. It’s a tightrope walk.

DNS Firewall to the rescue!

After analyzing the market for different solutions, CitraNET landed on DNS Firewall as their preferred solution. Delivered in the industry-standard Response Policy Zones (RPZ) format, DNS Firewall allows you to choose and implement the protection policies according to your risk profile.

CitraNET, with such a broad audience, are risk-tolerant, so they chose the feeds that best suited their use case to ensure they were only preventing access to indisputably malicious activity. (You can find out more about choosing the right feeds here.)

Working with local Spamhaus partner, Pipeline, CitraNET set up a trial to ensure the solution was compatible with their systems internally and met their delivery requirements. Results were monitored via logs before fully deploying DNS Firewall.

Set up was simple – the team used existing hardware to implement, and all users became protected in one single deployment. The impact was seen almost immediately. As malicious communications were automatically blocked in real time at the DNS level, fewer network resources were required to keep users accessing the internet. The network performance increased in terms of speed and performance.

CitraNET finally had assurance that their users and network were appropriately protected against malware, phishing sites, malicious traffic, and more – with the bonus of not having to set any firewall rules manually.

How does DNS Firewall work in practice?

In essence, this solution applies threat intelligence data to DNS resolver traffic to prevent DNS requests from resolving to known malicious IP addresses and domains. What do we mean by that?

When a user clicks on a URL link and queries their local DNS resolver, the DNS resolver checks against Spamhaus’ data – the DNS Firewall Threat Feeds. If the domain, IP, or nameserver is listed in one of the Feeds, the resolution of that link is blocked/redirected. If it is not listed, the user can access the link destination. This all happens in automatically in milliseconds making it a ‘set and forget’ solution.

The DNS Firewall Threat Feeds that Spamhaus makes available to customers range from “this IP is definitely bad – do not go near it” to “we are suspicious of this IP, so act with caution.” This places all of the control with CitraNET enabling them to choose the level of protection that meets their users’ needs.

The value of DNS Firewall

The solution has been in place since 2020, and in this time, CitraNET has seen network abuse complaints decrease dramatically. Customers are not getting infected, so their abuse desk is dealing with a reduced number of support tickets. This has led to constraints on internal resources dropping, so much so that they have been able to relocate one resource, assisting with costs-savings.

DNS Firewall Threat Feeds

Applied at the DNS level of your infrastructure, these threat feeds automatically stop users from accessing malicious sites including phishing and malware dropper websites.

These threat feeds can be integrated with existing recursive DNS servers, or for those who don’t manage their own DNS, we have a managed service available.

  • Reduce IT costs
  • Set and forget
  • Save money on risk insurance

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Case Study

Global managed cloud provider Rackspace is protecting customers and improving connectivity by using DNS Firewall threat feeds to block malicious domain traffic and botnet activity. Find out the challenges they were facing and how they overcame them.