Dial Technologies Configuration Guide, Cisco IOS Release 15.2S
Configuring Wholesale Dial Performance Optimization

Table Of Contents

Configuring Wholesale Dial Performance Optimization

Wholesale Dial Performance Optimization Feature Overview

How to Configure Automatic Command Execution

How to Configure TCP Clear Performance Optimization

Verifying Configuration of Preauthentication with ISDN PRI and Channel-Associated Signalling


Configuring Wholesale Dial Performance Optimization


This chapter describes the Wholesale Dial Performance Optimization feature in the following sections:

Wholesale Dial Performance Optimization Feature Overview

How to Configure Automatic Command Execution

How to Configure TCP Clear Performance Optimization

Verifying Configuration of Preauthentication with ISDN PRI and Channel-Associated Signalling


Note This task provides inbound and outbound performance optimization for wholesale dial customers who provide ports to America Online (AOL). It is configured only on Cisco AS5800 access servers.


Wholesale Dial Performance Optimization Feature Overview

Both the inbound and outbound aspects of this feature are enabled using the autocommand-options telnet-faststream command.

Outbound—Provides stream processing, allowing the output data processing to occur at the interrupt level. Being event driven, this removes polling and process switching overhead. In addition, the flow control algorithm is enhanced to handle the higher volume of traffic and to eliminate some out-of-resource conditions that could result in abnormal termination of the session.

Inbound—Provides stream processing with the same improvements as for outbound traffic. Also, it removes scanning for special escape characters in the data stream; this is very process-intensive and is not required for this application. (In other situations, the escape characters allow for a return to the privileged EXEC mode prompt (#) on the router.) In addition, Nagle's algorithm is used to form the inbound data stream into larger packets, thus minimizing packet-processing overhead.

This configuration is designed to provide more efficiency in the data transfers for AOL port suppliers who are using a Cisco network access server to communicate with a wholesale dial carrier.

The Cisco AS5800 access server is required to support all dial-in lines supported by two complete T3 connections (that is, 1344 connections) running TCP Clear connections to an internal host. The desired average data throughput for these connections is 6 kbps outbound and 3 kbps inbound.

When using the autocommand-options telnet-faststream command, no special character processing, including break recognition, is performed on incoming data from the dial shelf. This requires the TCP Clear connection to run as the sole connection on the TTY line. This sole connection is terminated by TTY line termination or TCP connection termination, with no EXEC session capability for the user. This has been implemented by specifying a new autocommand-options telnet-faststream command that, in conjunction with the autocommand telnet command with the /stream option, enables Telnet faststream processing. This capability is also available for TACACS/RADIUS attribute-value pair processing, because this processing uses the autocommand facility.

How to Configure Automatic Command Execution

The following are three options for configuring the autocommand telnet /stream line configuration command:

Automatic command execution can be configured on the lines.

Automatic command execution can be configured using user ID and password.

Automatic command execution can also be configured at a TACACS/RADIUS server, if the username authentication is to be performed there, rather than on the router.

To configure automatic command execution on the lines of a Cisco AS5800 universal network access server, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# line 1/3/00 1/11/143

Selects the lines to be configured and begins line configuration mode.

Step 2 

Router(config-line)# autocommand telnet aol-host 5190 /stream

Configures autocommand on the lines.

To configure automatic command execution using a user ID and password on a Cisco AS5800 universal network access server, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# username aol password aol

Defines the user ID and password.

Step 2 

Router(config)# username aol autocommand telnet aol-host 5190 /stream

Configures autocommand on the user ID.

You can also configure automatic command execution at a TACACS/RADIUS server if the username authentication is to be performed there rather than on the router. The AV-pair processing allows autocommand to be configured.

How to Configure TCP Clear Performance Optimization

To enable TCP Clear performance optimization, automatic command execution must be configured to enable Telnet faststream capability. To implement TCP Clear performance optimization on a Cisco AS5800 universal network access server, use the following commands beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# line 1/3/00 1/11/143

Selects the lines to be configured and begins line configuration mode.

Step 2 

Router(config-line)# autocommand telnet-faststream

Enables the TCP Clear performance optimization on the selected lines.

Verifying Configuration of Preauthentication with ISDN PRI and Channel-Associated Signalling

To check for correct configuration, use the show line command. In the following example, Telnet faststream is enabled under "Capabilities".


Router# show line 1/4/00

   Tty Typ     Tx/Rx    A Modem  Roty AccO AccI   Uses   Noise  Overruns   Int 
*   1/4/00 Digital modem - inout     -    -    -      1       0     0/0       - 
Line 1/4/00, Location: "", Type: "" 
Length: 24 lines, Width: 80 columns 
Status: PSI Enabled, Ready, Connected, Active, No Exit Banner 
  Modem Detected 
Capabilities: Hardware Flowcontrol In, Hardware Flowcontrol Out 
  Modem Callout, Modem RI is CD, Line usable as async interface 
  Hangup on Last Close, Modem Autoconfigure, Telnet Faststream 
Modem state: Ready 
Modem hardware state: CTS DSR  DTR RTS 
modem=1/4/00, vdev_state(0x00000000)=CSM_OC_STATE, bchan_num=(T1 1/2/0:7:20) 
vdev_status(0x00000001): VDEV_STATUS_ACTIVE_CALL. 

Group codes:    0, Modem Configured 
Special Chars: Escape  Hold  Stop  Start  Disconnect  Activation 
                ^^x    none   -     -       none 
Timeouts:      Idle EXEC    Idle Session   Modem Answer  Session   Dispatch 
                never         never                        none     not set 
                            Idle Session Disconnect Warning 
                              never 
                            Login-sequence User Response 
                             00:00:30 
                            Autoselect Initial Wait 
                              not set 
Modem type is 9600. 
Session limit is not set. 
Time since activation: never 
Editing is enabled. 
History is enabled, history size is 10. 
DNS resolution in show commands is enabled 
Full user help is disabled 
Allowed transports are telnet.  Preferred is lat. 
Automatically execute command "telnet 10.100.254.254 2145 /stream" 
No output characters are padded 






 
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any 
examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes 
only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental. 
 
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