Cisco Juniper handshaking

Unanswered Question
May 27th, 2008

Dear all

I have cisco 2800 router and a juniper j2300 router. I have to make it a serial comunication over the cisco to juniper

I have two question

1) The cisco cables are compatible with juniper or not ?

2)how to done the handshakinig between the cisco and juniper device.

Other things are

when i connect the juniepr Wic 1T to cisco 2T through the DTE(Juniper) DCE(cisco)cable then the juniper serail is dhowing up but the cisco shows serail Down

kindly help on this

thanks and regads

sanju kumar

I have this problem too.
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royalblues Tue, 05/27/2008 - 08:04

Have you defined clockrate under the Interface on the Cisco (DCE) side?


Harold Ritter Tue, 05/27/2008 - 09:38


1) You mentioned wic-1t and 2t but I suppose you are using the serial modules on both sides, right? If so, yes it should be ok.

2) For a back to back connection, you need to set the clockrate on the DCE. Also, JUNOS uses PPP as default encapsulation, whereas IOS uses hdlc. Make sure you change one side or the other.


sanjukumarsharma Tue, 05/27/2008 - 23:21

Dear Heitter

1)I had allready done this. But when i used to show interface on the juniper side it shows me that the clock source is not detected.

2)Juniper is currently using the x.21 to deal with this in cisco.

and finally

3)how to configure the juniper serial end as a DTE , plz tell me the clocking iin the juniper end as a DTE

plz help me on this

thanks and regards

sanju kumar

Harold Ritter Wed, 05/28/2008 - 05:30


1) - Are you using the following cable on the Juniper side: JX-CBL-X21-DTE ?

- Are you using the following cable on the Cisco side: CAB-SS-X21FC ? Are you using the

2) You don't need do do anything special as long as you have the right cable (DCE) and setting the clock rate.

3)You shouldn't need to do anything special on the Juniper side except for using the right cable (DTE). The DTE mode should be detected automatically.

If this doesn't work, please provide a "show interface extensive" from the JUNOS side and a "show interface " and "show controller " from the IOS side.

Also do not forget to change the encapsulation on one side or the other as the default values are different.



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