Warning message

  • Cisco Support Forums is in Read Only mode while the site is being migrated.
  • Cisco Support Forums is in Read Only mode while the site is being migrated.

effects of encryption on CPU usage level

Unanswered Question
Oct 30th, 2005
User Badges:


Does any one know the effects of different encryption algorithms on CPU usage levels on routers (lower end 1700, 1800, 2600, 2800 series) encrypting with software based encryption level, or any info regarding this issue.


  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (1 ratings)
thomas.chen Fri, 11/04/2005 - 12:09
User Badges:
  • Silver, 250 points or more

The following data ensures only the small amount of data can be processed when encryption is used.

Platform Throughput (max, fast-switching)

2610-12 -15K packets per second (pps)

2620/21 -25K pps

2650/51 -37K pps

2610/11XM- 20K pps

2620/21XM -30K pps

2650/51XM -40K pps

2691 -70K pps

dehghan Fri, 11/04/2005 - 23:24
User Badges:

Has there been an estimate or a test as to at what performance these devices can perform encryption in utilization or in through put?


aacole Tue, 11/08/2005 - 12:38
User Badges:
  • Bronze, 100 points or more

This is always a difficult one to answer, but to give some idea about this, I had a 2621XM with 2 2meg links bonded to 4 meg, with software compression.

The router CPU maxed out at 100% before the link was fully loaded. Users complained about droped and slow sessions, and it was not possible to connect to the router via telnet.

So my recommendation woud be to consider software encryption upto about 1meg, above that fit a hardware accelerator.


This Discussion