North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

How much will the cpu load increase when I apply CAR at C7513?

  • From: Woohyun Chang
  • Date: Wed Aug 12 13:03:43 1998

                   
  some WAN interfaces     R1          R2    some WAN interfaces
             -----------C7513      C7513------------
              		  |           |
	          	  |fe         |fe
		        ======switch=======

R2: 	C7513
	RSP2
	no VIP card
	cpu load: 18%
	FastEthernet: 
		outbound: 6Mbps
		inbound:  22Mbps
	Cisco IOS 11.1.18CC 
	RED is not available because 11.1.18CC does not provide RED without VIP card.
    
The input queue at the FastEthernet of R2 is insufficent because
there are many inbound packet more than outbound packet into some WAN interfaces at R2.
Therefore, packet drops happens at Fastethernet of R2.

I tried to increase the input queue of the FastEthernet of R2, and
I found that that is useless. So I'll try to apply CAR(committed access rate).

I have two questions.

1. If I apply CAR at FastEthernet of R2 for inbound traffic, 
   how much will cpu load of R2 increase? 
   I hope that the cpu load does not increase very high.
   The condition for the classification of IP traffic will be very simple.

2. Is it possible  that my work applying CAR will fix the packet drops at FastEthernet? 
   Will my work make queue available faster than before?

Regards,

/woohyun chang
[email protected]
BORANet Services
DACOM Corporation
Seoul, Korea
TEL+82-2-220-5209