To enable automatic detection of the encapsulation types in operation over a point-to-point link to a specified serial or ISDN interface, use the autodetect encapsulation interface configuration command. Use the no form of this command to disable automatic, dynamic detection of the encapsulation types in operation on a link.
autodetect encapsulation {v120 | ppp }
no autodetect encapsulation
v120 Enables interoperation with ISDN terminal adapters that use V.120 encapsulation but do not signal V.120 in the call Setup message. An ISDN interface that by default answers a call as synchronous serial with PPP encapsulation can change its encapsulation and answer such calls.
ppp Enables PPP encapsulation.
Disabled
Interface configuration
| Release | Modification | 11.2 | This command was introduced. |
|---|
At least one encapsulation type is required in the command, but you can specify additional encapsulation types.
Use this command to enable the specified serial or ISDN interface to accept calls and dynamically change the encapsulation in effect on the interface when the remote device does not signal the call type. For example, if an ISDN call does not identify the call type in the Lower Layer Compatibility fields and is using an encapsulation that is different from the one configured on the interface, the interface can change its encapsulation type dynamically.
Automatic detection is attempted for the first 10 seconds after the link is established or the first five packets exchanged over the link, whichever is first.
The following example configures BRI 0 to call and receive calls from two sites, use Point-to-Point Protocol (PPP) encapsulation on outgoing calls, and use Challenge Handshake Authentication Protocol (CHAP) authentication on incoming calls. This example also enables BRI 0 to configure itself dynamically to answer calls that use V.120 but that do not signal V.120.
interface bri 0 encapsulation ppp autodetect encapsulation v120 no keepalive dialer map ip 131.108.36.10 name EB1 234 dialer map ip 131.108 36.9 name EB2 456 dialer-group 1 isdn spid1 0146334600 isdn spid2 0146334610 isdn T200 1000 ppp authentication chap
| Command | Description |
|---|---|
| encapsulation | Sets the encapsulation method used by the interface. |
Printed for apswan@ctr.ap.nic.in on Wed Mar 5 22:32:57 PST 2003
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