Rate limiting restricts the number of requests a system accepts. It protects APIs and login endpoints from abuse. Proper thresholds balance security and usability. Logging rate-limit triggers aids forensic analysis.

Modern Wi-Fi networks should use WPA3 encryption. Default credentials must be changed immediately. Guest networks should be isolated from internal systems. Regular firmware updates reduce exposure to known vulnerabilities.

Border Gateway Protocol (BGP) routes traffic between autonomous systems. Route hijacking can redirect traffic maliciously. Security enhancements like RPKI validate route announcements. Monitoring route changes is critical for ISPs and enterprises.

Microsegmentation divides networks into small, isolated zones. Each workload has its own security policy. This limits east-west traffic during breaches. Software-defined networking often enables granular enforcement.

Virtual Private Networks (VPNs) create secure tunnels over public networks. Common technologies include IPsec and SSL/TLS-based VPNs. VPNs protect remote access and site-to-site connectivity. However, compromised credentials can undermine their effectiveness.

IPv6 introduces new protocols like Neighbor Discovery. While it improves address space and efficiency, it also creates new attack vectors. Security teams must configure IPv6 firewalls and disable unused transition mechanisms. Ignoring IPv6 can leave hidden vulnerabilities.

Network logs provide visibility into traffic patterns and security events. Centralized log management improves incident response. Correlating logs from firewalls, routers, and servers helps identify anomalies. Retention policies must balance compliance and storage costs.

Port security restricts which MAC addresses can connect to a switch port. This prevents unauthorized devices from plugging into open ports. Administrators can configure maximum MAC addresses per port. Violations can trigger shutdowns or alerts.

Network Access Control enforces policies for device access. Devices are evaluated based on compliance checks such as patch levels and antivirus status. Non-compliant devices can be quarantined. NAC strengthens endpoint security before granting network access.

IPsec secures IP communications through authentication and encryption. It operates in transport or tunnel mode. Commonly used in VPNs, IPsec ensures confidentiality and integrity across untrusted networks. Proper key exchange via IKE is critical for security.