Network & telephony
Firewall setup
Letting through only what is needed, in both directions
What this is about
A firewall is only as good as its rule set. We clear out rules that have accumulated over time, document every rule and regularly check whether it is still needed.
What is included
- Survey and assessment of the existing rules
- Clearing out old port forwards
- Rule set based on the principle that only what is necessary is allowed
- Logging of suspicious access
- Six-monthly review
Process
How we go about it.
Review
List all rules and ask for a justification of each.
Clean up
Remove anything unjustified and document the rest.
Harden
Limit access from outside to the bare minimum.
Monitor
Report anomalies and tighten rules as needed.
Frequent questions
This is what we are often asked.
Does that apply to a FritzBox as well?
Yes. It also has forwards that nobody needs any more, and which are visible from outside.
Will the change be noticeable in daily work?
If we do the job properly, no. We first check which services are actually in use.
How often should this be checked?
At least every six months, and whenever systems are added or removed.
Sollen wir uns das ansehen?
Ein kurzes Gespräch genügt, um einzuschätzen, was in Ihrem Betrieb sinnvoll ist — und was nicht.