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New Member

packet lost

We have an issue with a voice gateway. The scenario is:

GW3660 ----> ADSL -----> 7200 -----> internet

When I put the "sh call active voice brief" during a call I show:

20CA : 8828 1781354800ms.1 +3020 pid:7 Originate 09538xxxx active

dur 00:04:30 tx:5626/69666 rx:10695/180544

IP x.x.19x.x:17424 SRTP: off rtt:0ms pl:169880/3010ms lost:95/41/178 delay:80/60/150ms g729br8

media inactive detected:n media contrl rcvd:n/a timestamp:n/a

Telephony call-legs: 1

SIP call-legs: 1

H323 call-legs: 0

Call agent controlled call-legs: 0

SCCP call-legs: 0

Multicast call-legs: 0

Total call-legs: 2

When I heard the voice lost during the packet lost number increases but I deploy the QoS in the link ATM between GW and 7200.

I insert the tx-ring at 3, fragment delay on PPP at 4 (about 512 byte) and cRTP and LLQ in outbound of 3660.

Now I don't what anything else configure to resolve the issue.

Does anyone know how?

Thank you.



Re: packet lost

if you could provide some config output that would be nice.

perhaps changing your codec for a test from 729 to another, pref. 711 for starters. (if it's a bandwidth issue this will only make it worse)

you seem to have a bit of delay so verifying your QoS config, L2 & L3 would be a good start...paste if you can.

New Member

Re: packet lost


Here we are the QoS configuration in 3660:

interface ATM3/0

bandwidth 1024

ip address x1x.3x.1xx.6

ip nat outside

ip virtual-reassembly

no atm ilmi-keepalive


impedance 120-ohm

service-policy output VOIP

pvc 10/100

protocol ip x1x.3x.1xx.x broadcast

tx-ring-limit 3

oam-pvc 0

encapsulation aal5snap

protocol ppp Virtual-Template1

interface Virtual-Template1

bandwidth 1024

ip unnumbered ATM3/0

no ip route-cache cef

ip tcp header-compression iphc-format

load-interval 30

ppp multilink

ppp multilink fragment delay 4

ppp multilink interleave

max-reserved-bandwidth 50

ip rtp header-compression iphc-format


class-map match-any voice-control

match ip dscp cs3

match ip dscp af31

class-map match-any voice

match ip dscp ef



policy-map VOIP

class voice-control

bandwidth percent 2

class voice

priority 256

class class-default


In 7200 there is the same configuration except the policy VOIP in output interface because there some bugs that make instable the router.

Could it be that?