1- VPN and Firewalls Troubleshooting
2- Evaluating your policies to check how secure your network
3- software-based VPN / IPSec Setup and Configuration
4- Physical Firewalls configuration(Cisco, Juniper, Watch Guard, Palo-alto, Huawei, etc)
5- Intrusion Prevention System
6- Intrusion Detection System
I am also working on Fiverr. The link to my Fiverr profile is mentioned below you can check customer reviews there.
https://www.fiverr.com/users/nomi04_549