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Frame Relay Traffic Shaping and QOS

Is anyone out there using LLQ with Frame-Relay and Traffic Shaping? If so, I have a question. Since FRTF shapes your PVCs to control congestion, does that not somewhat defeat the mechanism in which to trigger QOS?

I have been trying to "Validate" that QOS is working with FRTF and CBWFQ and in order to do that, the first thing I want to see is FECNs and BECNs, but with FRTF turned on, they arnt there when I try to flood the interface(sh frame-relay pvc) however, the rudamentary testing appears that CBWFQ is dropping/matching is it working? Or isnt it?

Here is the relevant part of the config


class-map match-any Gold

match access-group 151

class-map match-any Bronze

match access-group 150

policy-map Test

class Gold

bandwidth 30

class Bronze

bandwidth 10


interface serial0

no fair-queue

frame-relay traffic-shaping

interface serial0/0.1

bandwidth 128

frame-relay class FRAMECLASS

frame-relay interface dlci 111


map-class frame-relay FRAMECLASS

frame-relay traffic-rate 128000 256000

no frame-relay adaptive shaping

frame-relay mincir 128000

service-policy output Test


access-list 151 permit icmp any any

access-list 150 permit tcp any any eq telnet


Remote> sh service-policy int

Serial 0/0.1: DLCI 111 -

Service-policy output: QOS

Class-map: Bronze (match-any)

249819 packets, 184093742 bytes

5 minute offered rate 196000 bytes, drop rate 97000 bps

0 packets, 0 bytes

5 min rate 149000 bps

Match: access-group 150

249819 packets, 184093742 bytes

5 min rate 196000 bps

Weighted Fair Queueing

Output Queue: Conversation 25

Bandwidth 10 (kbps) Max Threshold 64 (packets)

(pkts matched/bytes matched) 14563/11042224

(depth/total drops/no buffer-drops) 64/7489/0

Class-map: Gold (match-any)

756 packets, 36288 bytes

5 minute offered rate 0bps, drop rate 0 bps

Match: access-group 151

756 packets, 36288 bytes

5 minute offered rate 0 bps

Remote> sh frame-relay pvc 505


input pkts 396725 output pkts 294605 in bytes 2362828272

out bytes 747220333 dropped pkts 0 in pkts dropped 0

out pkts dropped 14538 out bytes dropped 10061844

late-dropped out pkts 14538 late-dropped out bytes 1061844

in FECN pkts 0 in BECN pkts 0 out FECN pkts 0

out BECN pkts 0 in DE pkts 0 out DE pkts 0

out bcast pkts 5128 out bcast bytes 663775

pvc create time 22:34:20, last time pvc status changed 22:35:29


If I remove FRTF, I get FECNS and BECNS but i need it to shape!...any ideas?

This is a 128kPVC/256k port




Re: Frame Relay Traffic Shaping and QOS

When you configure FRTS what happens is the router queues up the traffic and 'shapes' it to the speed of the PVC . in other words it will send your traffic out at a steady rate with no bursting. This is the reason you will not get FECN & BECN.

With CBWFQ you are guarenteeing bandwidth for the classes you define 30K for ping and 10K for telnet