Overview of IBM Networking

Usability Features

Usability Features

SNASw contains the following usability features designed to make SNA networks easier to design and maintain:

Dynamic CP Name Generation Support, page 236

Dynamic SNA BTU Size, page 236

DLUR Connect-Out, page 236

Responsive Mode Adaptive Rate-Based Flow Control, page 236

User-Settable Port Limits, page 237

Dynamic CP Name Generation Support

When scaling the SNASw function to hundreds or thousands of nodes, many network administrators find that defining a unique control point (CP) name on each node provides unnecessary configuration overhead. Dynamic CP name generation offers the ability to use the Cisco IOS hostname as the SNA CP name or to generate a CP name from an IP address. These facilities reuse one SNASw configuration across many routers and eliminate the specific configuration coordination previously required to configure a unique CP name for each SNA node in the network. Administrators can still explicitly configure the CP name within the SNASw configuration.

Dynamic SNA BTU Size

Most SNA node implementations require specific tuning of the SNA basic transmit unit (BTU) in the configuration. SNASw analyzes the interface maximum transfer units (MTUs) of the interfaces it uses and dynamically assigns the best MTU values for that specific port. For served dependent PU 2.0 devices, SNASw uses the downstream MAXDATA value from the host and dynamically sets the SNA BTU for that device to the MAXDATA value.

DLUR Connect-Out

SNASw can receive connect-out instructions from the IBM Communications Server for S/390. This function allows the system to dynamically connect-out to devices that are configured on the host with the appropriate connect-out definitions. This feature allows connectivity to SNA devices in the network that were traditionally configured for connect-out from the host.

Note DLUR connect-out can be performed over any supported data-link type.

Responsive Mode Adaptive Rate-Based Flow Control

Early HPR implementations failed to perform well in environments subject to packet loss (for example, Frame Relay, IP transport) and performed poorly when combined with other protocols in multiprotocol networks. SNASw implements the second-generation HPR flow control architecture, called Responsive

 

Cisco IOS Bridging and IBM Networking Configuration Guide

BC-236

78-11737-02

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IBM BC-201 manual Usability Features, Dynamic CP Name Generation Support, Dynamic SNA BTU Size, Dlur Connect-Out