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New Member

ISDN Adtran vs c2503

We are trying to carry out a connection ISDN among an equipment 2503 and a modem adtran ISU 2X64; what we desire in carrying out a link to 128kbps and the problem is that alone we achieve to raise it to 64kbps. I enclose I send them the configuración of the equipment and diagram of connection

C3660---------ISU2X64-----------Net ISDN------------C2503.

ser v.35 BRI


interface Serial2/1

description Enlace Prueba a Puebla

bandwidth 128

ip address

encapsulation ppp

dialer in-band

dialer map ip name Metepec broadcast 2193452

dialer-group 1

no fair-queue

pulse-time 1


interface BRI0

description enlace prueba Puebla

ip address

no ip directed-broadcast

encapsulation ppp

bandwidth 128

dialer idle-timeout 300

dialer map ip name c3660 broadcast 2190580

dialer-group 1

no fair-queue

ppp quality 20

ppp multilink


Re: ISDN Adtran vs c2503

To use multilink PPP you also need to issue the following command on the BRI interface:

dialer load-threshold 2 either

You need this to activate the second B-channel when the traffic reaches a certain level. When you pick a low number, the 2nd link should remain active almost all the time.

New Member

Re: ISDN Adtran vs c2503

Very well, if we want to initiate the conecction to 128, without expecting a threshold of traffic in the interface; that we should configure. On the other hand knows of an reestriccion or configuration specifies for the modem adtran, since this conexion is done well to 128 among equipment cisco; and with the modem alone we reach link of 64kbps


Re: ISDN Adtran vs c2503

You can try any of these options on the cisco to bring up 2 links ASAP:

dialer load-threshold 1

ppp multilink link min 2

Not sure about configuration options for the Adtran.

New Member

Re: ISDN Adtran vs c2503

Thanks by the Tip, already we test an option and i looking that really the call is generated to connect the second canal B, however itself is not achieved to establish the conexion. I enclose the result of a debug, that can comment me about?

20:39:35: CC_CHAN_GetIdleChanbri: dsl 0

20:39:35: Found idle channel B2

20:39:35: ISDN BR0: received HOST_PROCEEDING call_id 0x8103

20:39:35: ISDN BR0: received HOST_ALERTING call_id 0x8103

20:39:35: ISDN BR0: DEV_CALL_PROGRESSING: modem 3A bchan 1, call_id 8103, cause


20:39:35: ISDN BR0: HOST_ALERTING: VOICE ERROR 3A: bchan 1, call id 8103

20:39:35: ISDN BR0: received HOST_CONNECT call_id 0x8103

20:39:35: %LINK-3-UPDOWN: Interface BRI0:2, changed state to up

20:39:35: %ISDN-6-CONNECT: Interface BRI0:2 is now connected to 2193452

20:39:36: ISDN BR0: Event: Connected to 2193452 on B2 at 64 Kb/s

20:39:38: ISDN BR0: received HOST_DISCONNECT call_id 0x8103

20:39:38: ISDN BR0: Event: Call to was hung up.

20:39:38: ISDN BR0: process_disc_ack(): call id 0x8103, ces 1, call type DATA

20:39:38: %ISDN-6-DISCONNECT: Interface BRI0:2 disconnected from 2193452 , call

lasted 2 seconds

20:39:38: %LINK-3-UPDOWN: Interface BRI0:2, changed state to down

20:39:38: ISDN BR0: received HOST_DISCONNECT_ACK call_id 0x8103

20:39:38: ISDN BR0: HOST_DISCONNECT_ACK: call type is DATA


Re: ISDN Adtran vs c2503

It looks like the remote Adtran initiated the disconnect; you can have a look at "debug isdn q931" and "debug ppp neg" to confirm, but otherwise you should check the config of the Adtran to see why it's disconnecting.

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