Unanswered Question
Jun 14th, 2007
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Is possible to use SLIP on the PRI line? The customer used SLIP on async lines with analog modem (without any problem), but now he replaces the analog modem by ISDN modem and SLIP is not functional.

What commands he has to use on the int ser 0:15 for SLIP configuration? He tried to use encapsulation slip, but this command is not supported on this interface.

Thank you for your help.

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smothuku Thu, 06/14/2007 - 02:09
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Hi ,

encapsulation slip is not supported on pri line as we are using tty for remote-node dial-in sessions that use such protocols as SLIP, PPP, AppleTalk Remote Access (ARA), and XRemote.

You can use encapsultion ppp for pri line.why you want slip as encap. for pri ?



ROMAN TOMASEK Thu, 06/14/2007 - 02:15
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the customer has ATM which uses only SLIP protocol for communication. The customer would like to rise the speed of connection - so he uses the ISDN modem, but without success.

Is some possibility to use slip with ISDN?? Maybe some autodetect mechanism or tunneling?

Thank you


paolo bevilacqua Thu, 06/14/2007 - 03:29
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no, it not possible to use SLIP over ISDN. I think he should look better into upgrading the ATM to something that supports more modern method of connections. SLIP fell out of use about 10 years ago.

ROMAN TOMASEK Thu, 06/14/2007 - 03:37
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Is not possible to use the following config?


(conf)#vty-async virtual-template 1

(conf)#int Virtual-Template 1

(conf-if)# ip unnumbered Loopback10

(conf-if)#enca ppp

(conf-if)# peer default ip address pool SLIP

(conf)#interface Serial0:15

(conf-if)#autodetect encapsulation ppp v120

(conf)#line vty 0 3

(conf-line)#transport input telnet

(conf)#line vty 4

(conf-line)#transport input v120

(conf-line)#autocommand slip

Thank you.


paolo bevilacqua Thu, 06/14/2007 - 04:42
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V.120 and related protocols (asynch support for digital B-channels) are an area that has historically has caused many problems because of different interpretation of the standard by different vendors, so you can find that it may not work with the ISDN TA that you will be using. Good luck!

ROMAN TOMASEK Thu, 06/14/2007 - 05:27
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Thank you for your information. Tommorow I will test it. I hope that it will work.


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