 The use of VPNs with IPSec can further enhance security. SIP firewalls can prevent man-in-the-middle attacks and prevent authorized users from accessing voice mailboxes, call logs, directory services, and SO on. Billing fraud attacks have to be prevented as well. The application/service layer The use of Intrusion Detection Systems/Intrusion Prevention Systems (IDSs/IPSs) helps to strengthen security at this layer. IDSs/IPSs extend firewall security and help to prevent intrusive activity from malicious users. Such systems look for known patterns or signatures in permitted traffic. These signatures can be updated to stay current. The biggest challenge is zero-day attacks. The use of machine learning in IDSs/IPSs may prove an enhancement in this regard. In this section, we looked at various ways to enhance overall security for FMC solutions. The provider has the responsibility to provide sufficient security as well as sufficient QoS to their subscribers. On one hand, FMC makes the delivery and consumption of a variety of services such as voice, data, and video easier through the convergence of fixed and mobile networks. On the other hand, the mechanisms for securing FMC are still in their infancy. As a result, the providers of FMC need to carefully review the security implications of their network infrastructure. Some new security providers are entering this space. One such provider, Benu Networks, uses BNG with support for 5G Access Gateway Functions (AGFs). This allows operators to manage fixed-line subscribers using 5G Core. Benu Networks helps to provide Secure Access Service Edge (SASE). They provide the integration of SASE and 5G AGFs with virtual Broadband Network Gateway (vBNG). This helps in the faster deployment of FMC. Summary (Seehttps://benunetworks.com/cloud-native-bng-integrates-sase-a - - - 5g-agf/.) In this section, we looked at the security considerations for FMC. We looked at how to create robust security for FMC. Summary In this chapter, we looked at the factors driving the need for FMC. We look