From: Joe Martin (joe@xxxxxxxxxxxxxx)
Date: Tue Mar 05 2002 - 03:18:56 GMT-3
Check out:
http://www.cisco.com/univercd/cc/td/doc/cisintwk/intsolns/voipsol/ea_isd
.htm
What you will find with VoIP that echo due to delay(serialization,
codec, etc) so echo is a much larger problem here than traditional voice
circuits. The basics are that echo is caused by the side that doesn't
here it. So, it's the PSTN in your case. Though with a regular PBX it
may never show up. Again due to a very short delay in the TDM world.
Use the show voice active command and accout for the ERL levels and tune
the input gain and output attenuation and echo coverage outlined in the
above document and you 'should' be able to tune it out. The reason the
echo is not consistant is it depends where your calling to determine
echo. Once you find a number that causes it then that can be the test
number to use. Generally this is a call thru a long distance provider
as delay increases across long haul circuits. BTW: I think your card is
an NM-HDV-2T1-48 if it has 2 interfaces or a NM-HDV-1T1-24 or
NM-HDV-1T1-24E if it has one. The difference between the last two are
the number of DSPs. If it has 2 then it's the none E version.
Good luck on this. Echo is the toughest thing to resolve in VoIP.
Joe Martin
CCIE #5917
Consulting Systems Engineer
AVVID Specialist
Cisco Systems, Inc.
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Giveortake@aol.com
Sent: Monday, March 04, 2002 9:56 PM
To: ccielab@groupstudy.com
Subject: MF1-t1 voice problem Off Topic
I have a 3640 router with an HDV-mf1-t2 card.....
The router is an H323 gateway for my AAVID. I have a T1 which I am
directing all outbound LD and inbound 800 traffic. I also have some
copper terminated in FXO cards for local calls..
Trouble is I have SERIOUS ECHO on about 5 % of the calls that go through
the
T1. I can hear the echo on the IP phones, but the caller at the remote
end
across the PSTN never hears echo.
Telco tells me they have this provisioned as a 4-wire E&M 1 wink start
with
DTMF....
When I do a show contoller I get the following
NDT3640#show voice port 2/0:0
recEive and transMit Slot is 2, Sub-unit is 0, Port is 0
Type of VoicePort is E&M
Operation State is DORMANT
Administrative State is UP
The Last Interface Down Failure Cause is Administrative Shutdown
Description is not set Noise Regeneration is enabled Non Linear
Processing is enabled Music On Hold Threshold is Set to -38 dBm In
Gain is Set to 0 dB Out Attenuation is Set to 0 dB Echo Cancellation
is enabled Echo Cancel Coverage is set to 16 ms Playout-delay Mode is
set to default Playout-delay Nominal is set to 60 ms Playout-delay
Maximum is set to 200 ms Playout-delay Minimum mode is set to default,
value 40 ms Connection Mode is plar Connection Number is 100 Initial
Time Out is set to 10 s Interdigit Time Out is set to 10 s Ringing
Time Out is set to 180 s Companding Type is u-law Rx A bit no
conditioning set Rx B bit no conditioning set Rx C bit no
conditioning set Rx D bit no conditioning set Tx A bit no
conditioning set Tx B bit no conditioning set Tx C bit no
conditioning set Tx D bit no conditioning set Rx Seize ABCD bits =
1111 Default pattern Rx Idle ABCD bits = 0000 Default pattern Tx Seize
ABCD bits = 1111 Default pattern Tx Idle ABCD bits = 0000 Default
pattern Ignored Rx ABCD bits = BCD Region Tone is set for US
Analog Info Follows:
Currently processing none
Maintenance Mode Set to None (not in mtc mode)
Number of signaling protocol errors are 0
Impedance is set to 600r Ohm
Wait Release Time Out is 30 s
Station name None, Station number None
Voice card specific Info Follows:
Operation Type is 2-wire
E&M Type is 1
Signal Type is wink-start
Dial Type is dtmf
In Seizure is inactive
Out Seizure is inactive
Digit Duration Timing is set to 100 ms
InterDigit Duration Timing is set to 100 ms
Pulse Rate Timing is set to 10 pulses/second
InterDigit Pulse Duration Timing is set to 750 ms
Clear Wait Duration Timing is set to 400 ms
Wink Wait Duration Timing is set to 200 ms
Wait Wink Duration Timing is set to 550 ms
Wink Duration Timing is set to 200 ms
Delay Start Timing is set to 300 ms
Delay Duration Timing is set to 2000 ms
Dial Pulse Min. Delay is set to 140 ms
Percent Break of Pulse is 60 percent
Auto Cut-through is disabled
Dialout Delay for immediate start is 300 ms
You will notice that it states I am set up for 2-wire E&M. With VIC
cards,
I can go in and type operation 4 wire. Apparently I can not do the same
with
the T1 card. I can only define the DS0-groups for signalling E&M wink
start
but it doesnt give me the option of 2 or 4 wire.. Wondering if this is
part
of my problem..
I also have TWO 800 #'s pointing to this T1 and Telco/Sprint is supposed
to
be sending me seperate DNIS for each one. This wasnt working so I
had to
go with a connection plar statement and direct all inbound to a single
extension. Opened TAC case, we ran some debugs, and their conclusion
was
that SPrint is not sending any digits. Sprint is adamant that they
are
sending the digits.
At a loss..... If anyone has any suggestionn on my ECHO or DNIS issue
any
thoughts would be appreciated..
Below is the actual router config..
NDT3640#show run
Building configuration...
Current configuration : 2434 bytes
!
version 12.1
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname NDT3640
!
logging rate-limit console 10 except errors
enable secret 5 $1$K0Gy$Xezvv6R8N3WFOKgdnuZki1
!
username all
!
!
voice-card 2
!
ip subnet-zero
!
!
no ip finger
ip name-server 204.117.214.10
ip name-server 199.2.252.10
!
no mgcp timer receive-rtcp
call rsvp-sync
!
!
!
!
!
!
!
controller T1 2/0
framing esf
linecode b8zs
ds0-group 0 timeslots 1-12 type e&m-wink-start
!
controller T1 2/1
!
!
interface Loopback0
ip address 200.0.0.1 255.255.255.255
h323-gateway voip bind srcaddr 200.0.0.1
!
interface FastEthernet3/0
no ip address
duplex auto
speed auto
!
interface FastEthernet3/0.1
encapsulation isl 2
ip address 10.1.0.24 255.255.0.0
no ip redirects
!
interface FastEthernet3/0.2
encapsulation isl 3
ip address 10.2.0.1 255.255.0.0
no ip redirects
!
interface Serial3/0
no ip address
encapsulation frame-relay
service-module t1 timeslots 1-12
frame-relay lmi-type ansi
!
interface Serial3/0.1 point-to-point
ip address 10.100.0.1 255.255.255.0
frame-relay interface-dlci 30
!
router eigrp 1
network 10.0.0.0
network 200.0.0.0
no auto-summary
no eigrp log-neighbor-changes
!
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.0.4
no ip http server
!
!
voice-port 0/0/0
no vad
connection plar 100
!
voice-port 0/0/1
no vad
connection plar 100
!
voice-port 0/1/0
no vad
connection plar 100
!
voice-port 0/1/1
no vad
connection plar 100
!
voice-port 2/0:0
echo-cancel coverage 16
no vad
connection plar 100
!
dial-peer cor custom
!
!
!
dial-peer voice 1 pots
destination-pattern 9T
port 0/0/0
!
dial-peer voice 2 pots
destination-pattern 9T
port 0/0/1
!
dial-peer voice 3 pots
destination-pattern 9T
port 0/1/0
!
dial-peer voice 4 pots
destination-pattern 9T
port 0/1/1
!
dial-peer voice 5 pots
destination-pattern 91[2-7]T
direct-inward-dial
port 2/0:0
prefix 1
!
dial-peer voice 6 voip
destination-pattern 1..
session target ipv4:10.2.0.10
dtmf-relay h245-alphanumeric
codec g711ulaw
no vad
!
dial-peer voice 7 voip
destination-pattern 0208
session target ipv4:10.2.0.10
dtmf-relay h245-alphanumeric
no vad
!
dial-peer voice 8 voip
destination-pattern 5959
session target ipv4:10.2.0.10
dtmf-relay h245-alphanumeric
no vad
!
!
line con 0
transport input none
line aux 0
line vty 0 4
password alpha4
login
!
end
NDT3640#
Thanks,
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:56:53 GMT-3