Network-based attacks pose a strong threat to the Internet landscape. There are different possibilities to encounter these threats. On the one hand attack detection operated at the end-users’ side, on the other hand attack detection implemented at network operators’ infrastructures. An obvious benefit of the second approach is that it counteracts a network-based attack at its root. It is currently unclear to which extent countermeasures are set up at Internet scale and which anomaly detection and mitigation approaches of the community may be adopted by ISPs. We present results of a survey, which aims at gaining insight in industry processes, structures and capabilities of IT companies and the computer networks they run. One result with respect to attack detection is that flow-based detection mechanisms are valuable, because those mechanisms could easily adapt to existing infrastructures. Due to the lack of standardized exchange formats, mitigation across network borders is currently uncommon.