How is firewall capacity calculated?
If a firewall is sized by internet line speed, capacity can fall short once security services are switched on. Concurrent sessions, new sessions per second, application traffic, SSL inspection, VPN, threat profiles, log volume and the HA scenario should be measured together.
How do SSL inspection and VPN load affect the choice?
TLS decryption adds cryptographic processing and certificate operations; VPN adds load depending on tunnel count, encryption and the user/branch profile. The different throughput figures on a vendor datasheet should be compared under the same test conditions as the security profile you will use.
Central management and logging criteria
Across multiple devices, the need for templates, separation of duties, change history and bulk policy management drives the central management decision. On the logging side, daily volume, retention, search, time synchronization, SIEM forwarding and personal-data requirements are sized.
Enterprise firewall selection checklist
The short checklist below is a practical field reference for enterprise firewall selection projects:
| Control Area | Expected Output |
|---|---|
| Traffic profile | Peak bandwidth, sessions, applications and growth |
| Security load | SSL, VPN and active profiles |
| Operations | Central management, permissions and change |
| Evidence | PoC result, logging and failover measurement |