HP-UX IPSec vA.02.00 Performance and Sizing White Paper

CPU Utilization
Figure 8 shows the percentage of the CPU used by the sending system. CPU utilization for ESP-AES-
HMA
C-SHA1 is lower than CPU utilization rates for ESP-DES-HMAC-SHA1 and ESP-3DES-HMAC-
SHA1, even though ESP- AES-HMAC-SHA1 provides the strongest encryption. CPU utilization for ESP-
DES-HMAC-SHA1 and ESP-AES-HMAC-SHA1 decreases as the packet size increases, while CPU
utilization with ESP-3DES-HMAC-SHA1 remains consistently high.
Figure 8. One-Way, Itanium CPU Utilization for Raw IP, ESP-AES-HMAC-SHA1, ESP-DES-HMAC-SHA1, ESP-3DES-HMAC-SHA1
Service Demand
Figure 9 shows the service demand levels for ESP-AES
-HMAC-SHA1, ESP-DES-HMAC-SHA1, and ESP-
3DES-HMAC-SHA1. Lower service demand levels indicate greater efficiency. Of the three IPsec
transfer types, the service demand levels are lowest (most efficient) for ESP-AES-HMAC-SHA1.
Figure 9. One-Way Itanium Service Demand for Raw IP, ESP-AES-HMAC-SHA1, ESP-DES-HMAC-SHA1, ESP-3DES-HMAC-SHA1
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