From: Le Ba Duy Man (manlbd.hcm@ct-in.com.vn)
Date: Wed Mar 25 2009 - 00:10:22 ART
I changed the requirement a bit to "traffic that conform the guaranteed
bandwidth 80kbps will be marked with MPLS EXP 3, traffic in excess the
guaranteed rate but within the burst rate (800kps) should be marked with an
MPLS EXP 1, traffic in excess of the burst rate should be drop"
I labbed up, tested by ping 100 packet with size 2000 bytes with below
result:
Option 1: CAR
Rack1R3#sho run int s1/2
Building configuration...
Current configuration : 304 bytes
!
interface Serial1/2
ip address 10.1.13.3 255.255.255.0
rate-limit input 80000 15000 15000 conform-action
set-mpls-exp-imposition-transmit 3 exceed-action continue
rate-limit input 800000 150000 150000 conform-action
set-mpls-exp-imposition-transmit 1 exceed-action drop
serial restart-delay 0
Rack1R3#sho int s1/2 rate-limit
Serial1/2
Input
matches: all traffic
params: 80000 bps, 15000 limit, 15000 extended limit
conformed 145 packets, 165800 bytes; action:
set-mpls-exp-imposition-transmit 3
exceeded 58 packets, 37252 bytes; action: continue
last packet: 6464ms ago, current burst: 0 bytes
last cleared 00:00:29 ago, conformed 44000 bps, exceeded 10000 bps
matches: all traffic
params: 800000 bps, 150000 limit, 150000 extended limit
conformed 58 packets, 37252 bytes; action:
set-mpls-exp-imposition-transmit 1
exceeded 0 packets, 0 bytes; action: drop
last packet: 10440ms ago, current burst: 0 bytes
last cleared 00:00:29 ago, conformed 10000 bps, exceeded 0 bps
Option 2: Using MQC 1 rate 3 colors
Rack1R3#sho policy-map 2R3C
Policy Map 1R3C
Class class-default
police cir 80000 bc 2500 be 25000
conform-action set-mpls-exp-imposition-transmit 3
exceed-action set-mpls-exp-imposition-transmit 1
violate-action drop
Rack1R3#sho policy-map int s1/2
Serial1/2
Service-policy input: 1R3C
Class-map: class-default (match-any)
203 packets, 203052 bytes
5 minute offered rate 9000 bps, drop rate 1000 bps
Match: any
police:
cir 80000 bps, bc 2500 bytes, be 25000 bytes
conformed 119 packets, 151196 bytes; actions:
set-mpls-exp-imposition-transmit 3
exceeded 82 packets, 49828 bytes; actions:
set-mpls-exp-imposition-transmit 1
violated 2 packets, 2028 bytes; actions:
drop
conformed 8000 bps, exceed 6000 bps, violate 1000 bps
Option 3: Using MQC 2 rates 3 colors
Rack1R3#sho policy-map 2R3C
Policy Map 2R3C
Class class-default
police cir 80000 bc 2500 pir 800000 be 25000
conform-action set-mpls-exp-imposition-transmit 3
exceed-action set-mpls-exp-imposition-transmit 1
violate-action drop
Rack1R3#sho policy-map int s1/2
Serial1/2
Service-policy input: 2R3C
Class-map: class-default (match-any)
202 packets, 202968 bytes
5 minute offered rate 7000 bps, drop rate 0 bps
Match: any
police:
cir 80000 bps, bc 2500 bytes
pir 800000 bps, be 25000 bytes
conformed 115 packets, 148560 bytes; actions:
set-mpls-exp-imposition-transmit 3
exceeded 87 packets, 54408 bytes; actions:
set-mpls-exp-imposition-transmit 1
violated 0 packets, 0 bytes; actions:
drop
conformed 5000 bps, exceed 2000 bps, violate 0 bps
So Option 2 & 3 seems producing the same result whereas Option 1 does
differently. Can anyone share thoughts about this?
BTW, I have two question regarding Bc, Be value:
- With CAR: Bc (bits) = CIRx1.5 , Be=2xBc. Is it correct?
- How can we calculate the Bc, Be value for 1 rate, 3 color policing?
Thanks
_____
From: Pavel Bykov [mailto:slidersv@gmail.com]
Sent: Wednesday, March 25, 2009 8:11 AM
To: Le Ba Duy Man
Cc: ccielab@groupstudy.com; rintrum@gmail.com
Subject: Re: QOS: Policing
Think about the requirements.
What is being asked? The thing that should pop into your mind immediately is
two continuous rates.
Therefore, only 2R3C (two rate three color policer) will do the job.
Option 2 is therefore out of the question.
Option 1 and 3 are similar. 1 is configured using legacy CAR and 3 is
configured using MQC and CIR/PIR combination with proper actions.
But option 1 is tiny bit less precise then option 3. So Option 3 is he best.
Also, in practice, 3 would be preferred, because we don't want use legacy
unless there is a good reason, and I don't see this reason from here.
On Sun, Mar 22, 2009 at 9:36 AM, Le Ba Duy Man <manlbd.hcm@ct-in.com.vn>
wrote:
Hi group,
I have the following scenario: Configure the router that traffic coming in
that conforms to the guaranteed banwidth (2.5Mbps) is marked with an MPSL
EXP 1. Traffic in excess the guaranteed rate but within the burst rate
(7Mbps) should be marked with an MPLS EXP 0. Traffic in excess of the burst
rate should be drop.
I have three possile solution for this
1. Using CAR
interface FastEthernet0/0
rate-limit input 2496000 468750 468750 conform-action set-mpls-exp-transmit
1 exceed-action continue
rate-limit input 7000000 1312500 1312500 conform-action
set-mpls-exp-transmit 0 exceed-action drop
2. Using MQC one rate, three color policing
policy-map 1RATE_3COLOR
class class-default
police cir 2500000 bc 39062 be 109375
conform-action set-mpls-exp-transmit 1
exceed-action set-mpls-exp-transmit 0
violate-action drop
3. Using MQC two rate, three color policing
policy-map 2RATE_3COLOR
class class-default
police cir 2500000 pir 7000000
conform-action set-mpls-exp-transmit 1
exceed-action set-mpls-exp-transmit 0
violate-action drop
Which one is the most correct and why?
Thanks,
Rin
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