How to connect two Routers via BRI ISDN?

[Daniel Flieth]

Hello,

i want to connect my two Cisco Routers via the BRI Interface in both routers.

I thought i could configure the first router as network side and the second as User Side

Network Side:

interface BRI0/1/0

no ip address

isdn switch-type basic-net3

isdn protocol-emulate network

isdn layer1-emulate network

isdn incoming-voice voice

isdn skipsend-idverify

line-power

User Side:

interface BRI0/1/0

no ip address

isdn switch-type basic-net3

isdn point-to-point-setup

isdn incoming-voice voice

isdn tei-negotiation first-call

But this will not work.

Do you have any idea? I also tried is with static tei.

Best Regards

Daniel

[acampbell]

Daniel,

Yes this does work

You need to use a BRI cross cable

3 -------------5

4 --------------6

5 --------------3

6 --------------4

See link http://www.cisco.com/en/US/tech/tk652/tk653/technologies_configuration_example09186a008010ef6c.shtml

Also on both interfaces add

isdn point-to-point-setup

isdn static-tei 0

Regards,
Alex.
Please rate useful posts.

[Daniel Flieth]

Hello Alex,

Thank you for your answer. Today i´ve got the following q921 output

Jan  9 12:36:39.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:40.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:41.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:42.073: ISDN BR0/1/0 Q931: Ux_DLRelInd: DL_REL_IND received from L2

Jan  9 12:36:42.073: ISDN BR0/1/0 Q921: User TX -> IDVER ri=0 ai=0

Jan  9 12:36:44.073: ISDN BR0/1/0 Q921: User TX -> IDVER ri=0 ai=0

Jan  9 12:36:46.073: ISDN BR0/1/0 Q921: L2_EstablishDataLink: sending SABME

Jan  9 12:36:46.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:47.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:48.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:49.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:50.073: ISDN BR0/1/0 Q931: Ux_DLRelInd: DL_REL_IND received from L2

Jan  9 12:36:50.073: ISDN BR0/1/0 Q921: User TX -> IDVER ri=0 ai=0do sh isdn st

Jan  9 12:36:52.073: ISDN BR0/1/0 Q921: L2_EstablishDataLink: sending SABME

Jan  9 12:36:52.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0

Jan  9 12:36:53.073: ISDN BR0/1/0 Q921: User TX -> SABMEp sapi=0 tei=0atus

Global ISDN Switchtype = basic-net3

ISDN BRI0/1/0 interface

        dsl 2, interface ISDN Switchtype = basic-net3

    Layer 1 Status:

        ACTIVE

    Layer 2 Status:

        TEI = 0, Ces = 1, SAPI = 0, State = AWAITING_ESTABLISHMENT

    Layer 3 Status:

        0 Active Layer 3 Call(s)

    Active dsl 2 CCBs = 0

    The Free Channel Mask:  0x80000003

ISDN BRI0/1/1 interface

        dsl 3, interface ISDN Switchtype = basic-net3

    Layer 1 Status:

        DEACTIVATED

    Layer 2 Status:

        Layer 2 NOT Activated

    Layer 3 Status:

        0 Active Layer 3 Call(s)

    Active dsl 3 CCBs = 0

    The Free Channel Mask:  0x80000003

    Total Allocated ISDN CCBs = 0

Maybe it was because i only configured isdn point-to-point-setup on the user side?

[acampbell]

Daniel,

Look at the output you have shown:-

ISDN BRI0/1/1 interface

dsl 3, interface ISDN Switchtype = basic-net3

Layer 1 Status:

DEACTIVATED

The physical level is not connected

Check cable etc

Notice that the debug only has TX frames no sign of any RX.

Regards,
Alex.
Please rate useful posts.

[Daniel Flieth]

Hello Alex,

no BRI0/1/0 is active.

I also wonder why only TX Frames and no RX Frames.

Dont really know why.

[acampbell]

Daniel,

The NETWORK end will alway try to stay up whether a cable

is plugged in or not and will continue to send out SABME frames until it

receives a UA frame

You may need line power at the USER end.

On the the NETWORK end try adding.

int bri 0/1/0

line-power

Please also recheck that the cable is a ISDN/BRI cross as I have

detailed above.

Regards,
Alex.
Please rate useful posts.