This document describes the role of Challenge Handshake Authentication Protocol (CHAP) authentication configured under cellular interface. It also clarifies the logic and sequence of steps that take place at the time of initialization of cellular interface in Cisco 3G/4G routers.
Cisco recommends that you have basic knowledge of 3G and 4G.
cellular interface configuration
dialer list for triggering a dial
route for the cellular interface
Note: There are the six sections that must be configured in order to have a working cellular connection.
This document is not restricted to specific software and hardware versions.
The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.
These are the standard cellular configurations that you should have for any 3G/4G connection.
Assume that you have two profiles here, for example:
To modify the Default Profile 1 or 2, you need to re-create the profile. You are asked twice to confirm whether you want to overwrite the profile that already exists.
How to recreate profile 1 is shown in this example:
Router#cellular lte profile create 1 PROFILE-1@CISCO.COM Warning: You are attempting to modify the attach profile. Please consult the service provider before doing so. Modem power cycle required for change to take effect.
PDP Type = IPv4 Access Point Name (APN) = Authentication = NONE
Profile 1 already exists with above parameters. Do you want to overwrite? [confirm]
Profile 1 will be overwritten with the following values:
PDP type = IPv4 APN = PROFILE-1@CISCO.COM Authentication = NONE
Are you sure? [confirm] Profile 1 written to modem
Use this section in order to confirm that your configuration works properly.
For 3G/4G fixed routers and modules, the encapsulation under the cellular interface is for the communication between IOS and modem. It has nothing to do with the communication or negotiation between modem and the service provider. In older modems, for communication between IOS and modem, PPP was used. In newer LTE modems, SLIP frames are used for the same purpose.
The parameters required to negotiate with service provider like authentication, username/password credentials and so on must be configured in cellular profile and not under cellular interface or dialer interface.
This section provides information you can use in order to troubleshoot your configuration.