Silke is a security expert at Nokia Bell Labs (Research branch of Nokia). She holds a PhD in Mathematics and has 18 years of experience in mobile security research and standardization. In her current research she investigates new and existing mobile network security attacks using SS7, Diameter and GTP protocols via the interconnection network and how to counter those attacks in 4G/5G networks. She found many 4G related IPX attacks and countermeasures e.g. Location Tracking (NATO CyCon), DoS (Black Hat EU 2016), cellular data interception (34C3 Chaos Computer Congress). She drives in the operator association GSMA the security of cellular network and being responsible there for the Diameter Signaling Security Specification. She served as a special matter expert on cellular security to the US Federal Communication Commission and to the European Union Agency for Network and Information Security. She is rapporteur of ten 3GPP security specifications and has a long track record of security publications. Currently, she is actively supporting the 5G Roaming security developments. For her the interesting part is fixing problems in world wide network without breaking it, not finding an issue. @SHoltmanns