Specifications

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Cisco AS5x00 Case Study for Basic IP Modem Services
11/24/1999
Section 2 Commissioning the Cisco AS5300 Hardware
Testing Asynchronous-Shell Connections
Task 7. Testing Asynchronous-Shell Connections
This task verifies that the following components are working:

The physical asynchronous data path

Basic modem links

Basic IP functionality to support shell sessions
The Cisco IOS provides a command-line interface (CLI) called the EXEC.
The EXEC:

Can be accessed by dialing in with a modem

Provides access to terminal-shell services (no PPP) to do the following:
`
Modify configuration files
`
Change passwords
`
Troubleshoot possible problems including modem connections
`
Access other network resources by using telnet
During this task, some administrators try to make complex services function such as PPP-based Web
browsing. Do not jump ahead. Many other elements still need to be configured (for example, PPP and
IPCP). The asynchronous-shell test ensures that the EXEC’s login prompt can be accessed by a client
modem. Taking a layered approach to building a network isolates problems and saves you time.
Step 1
Locate a client PC, client modem, and analog line. From the client PC, open a terminal emulation
program (such as Hyper Terminal, not Dial-Up Networking) and connect to the client modem.
Figure 2-6 shows the network environment for this test.
Figure 2-6 Test Environment
Step 2
From a terminal-emulation program, test your RS-232 connection to the client modem. Enter the
at
command. The modem returns the prompt “OK.”
at
OK
Step 3
Dial the PRI telephone number assigned to the NAS (in this example the number is 5551234). After the
modem successfully connects, a connect message appears.
atdt5551234
CONNECT 28800 V42bis
Note
Many modems support the
a/
command, which recalls the last AT command. The
ath
command hangs up a modem call. The
atdl
command dials the last telephone
number.
Client PC
Cisco AS5300
with integrated
modems
Default
gateway
Client
modem
PSTN
POTS line PRI lines
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