Isdn issue in USA

Massimo Baschieri · ‎10-29-2007

Hi all,

I've got some troubles to make an isdn backup connection working from a branch office in USA to a HQ in Italy.

In any way I can't make the call be successfull if I call from the USA router to Italy, the calls from Italy to Usa works like a charm!!!!

The logs I've got during the failed attempts are the following:

Oct 29 07:30:34.074: ISDN BR1/0 Q931: TX -> SETUP pd = 8 callref = 0x3E

Bearer Capability i = 0x8890218F

Standard = CCITT

Transfer Capability = Unrestricted Digital

Transfer Mode = Circuit

Transfer Rate = 64 kbit/s

Channel ID i = 0x83

Keypad Facility i = '01139051aaaaaaa'

Oct 29 07:30:34.234: ISDN BR1/0 Q931: RX <- SETUP_ACK pd = 8 callref = 0xBE

Channel ID i = 0x89

Oct 29 07:30:38.298: ISDN BR1/0 Q931: RX <- CALL_PROC pd = 8 callref = 0xBE

Oct 29 07:30:38.830: ISDN BR1/0 Q931: RX <- DISCONNECT pd = 8 callref = 0xBE

Cause i = 0x839F - Normal, unspecified

Signal i = 0x03 - Network congestion tone on

Oct 29 07:30:38.834: ISDN BR1/0 Q931: TX -> RELEASE pd = 8 callref = 0x3E

Oct 29 07:30:38.870: ISDN BR1/0 Q931: RX <- RELEASE_COMP pd = 8 callref = 0xBE

Reading the cisco docs it seems that the above error means the carrier doesn't know how to route the call, excluding that I'm dialing the wrong number I can think that the carrier forbids international calls by contract, but the carrier itself keeps telling me that it's not the case.

I've got little experience with Usa isdn lines and I'm really clueless, so I ask for your help.

Here follows a piece of the Usa router config, which is a 2811 with a 4bri interface, the Italy router is a 2821 with a pri interface aboard.

interface BRI1/0

no ip address

encapsulation ppp

no ip mroute-cache

dialer pool-member 100

dialer pool-member 1

isdn switch-type basic-ni

isdn point-to-point-setup

isdn spid1 262xxxxxxx0101 xxxxxxx

isdn spid2 262yyyyyyy0101 yyyyyyy

ppp authentication chap

ppp multilink

!

interface BRI1/1

no ip address

encapsulation ppp

no ip mroute-cache

dialer pool-member 100

dialer pool-member 1

isdn switch-type basic-ni

isdn point-to-point-setup

isdn spid1 262wwwwwww0101 wwwwwww

isdn spid2 262zzzzzzz0101 zzzzzzz

ppp authentication chap

ppp multilink

!

.

!

interface Dialer1

ip address 10.177.254.2 255.255.255.0

encapsulation ppp

no ip mroute-cache

dialer pool 1

dialer remote-name 2811VPN2

dialer idle-timeout 300

dialer string 01139051aaaaaaa class italy

dialer load-threshold 50 either

dialer-group 2

compress stac

no cdp enable

ppp authentication chap

ppp multilink

!

.

!

map-class dialer italy

dialer isdn speed 56

However both bri interfaces shows the same issue when calling to Italy, but they can succesfully call to each other!!!

Tnx,

Max.

Richard Burts · ‎10-29-2007

Max

It may be especially significant that they can successfully call each other. This would eliminate many potential problems such as faulty hardware or incorrect cabling, or misconfigured ISDN switch. If they can call each other then I do not see that the problem can be on the router or in the router configuration.

I do not have much experience with this, but I suspect that the problem may be in the provisioning of the ISDN by the provider. They may claim that they support international calling (and that probably is true). But it surely sounds like the provisioning of these particular ISDN circuits do not include that feature. I would suggest that you ask the provider to check carefully on the provisioning of these circuits.

HTH

Rick

HTH

Rick

Massimo Baschieri · ‎10-29-2007

Hi Rick,

first of all tnx for your incredibly quick reply!!!

Not only the two lines can call to each other, but they both can receive calls from Italy.

Me too I'm convinced that it has to be a provisioning issue, but the provider keeps assuring the customer that there are no restrictions to international calls regarding those contracts.

In fact the carrier keeps rejecting the calls with the errors you have seen and the calls never come to the Italian side.

By your experience cannot it be an issue related to the different speed of the Italian and north american lines (56k versus 64k)?

I've tried to remove the related class map with bad luck, but maybe it's a carrier or router issue that produces a mesleading error message.

Tnx again,

Max.

paolo bevilacqua · ‎10-29-2007

Massimo,

it is not due to 56/64K, everyone uses 64Kbps.

As suggested by Rick, seems like the provider doesn't correctly route international calls.

One thing they may got wrong is that this is a data call, that is always a little special becase it's ISDN international, they may expect you to do voice calls only.

Does it produce the same error if you do "isdn test call interface ... ?

Massimo Baschieri · ‎10-29-2007

Hi Paolo,

your name sounds familiar :-)

Yes, it produces the same error if I try with "isdn test call etc...."

All is pointing to a provider issue, but the provider swears to the customer that all is fine ad international calls are allowed, the customer is believing him, all in all the provider is loosing some bargain blocking international calls.

I've got no answers at all.

Tnx,

Max.

paolo bevilacqua · ‎10-29-2007

Hi Massimo,

Then play by the rules, fax or email to telco the trace showing the parameters used during the call and ask the ISP to trace the reason for the call failing.

Remind them that this is a data call, again they may not be prepared to handle that on an international basis. Perhaps the international carrier they are sending the call to, is ultimately responsible.

Tell these things to your customer too and you should be OK.

Perhaps you knew me from some prehistoric age ?

good luck!

Massimo Baschieri · ‎10-29-2007

I've also tried to perform some "isdn test call etc..." to other Italian numbers where I've the control on the routers, but in any case I've seen the call coming.

Tnx again,

Max.