z/OS Communications Server education

Resolving The Problem

z/OS Communications Server has a long list of components spanning both SNA and TCPIP. In an effort to provide insight into configuring, using and debugging those components the z/OS CS team is providing these downloadable education modules.

Listed below are the current education modules available for download. Click on the title to go to the download document.

Diagnosing Enterprise Extender (EE) Problems
What happens between VTAM and TCPIP when Enterprise Extender session/connections start? Where do I look when there is a problem? Do I start with TCPIP trace or VTAM trace or both? If so, what traces do I need and what do I look for in those traces? Join us as we look at traces of EE sessions/connections and what happens under the covers for VTAM and TCPIP

Understanding Enterprise Extender, Part 1 - Concepts and Considerations
Enterprise Extender (EE) is a valuable technology that allows you to preserve your SNA application investment while exploiting the advantages of a consolidated IP backbone. EE allows you to utilize an IP network for the transport of SNA traffic, including SNA traffic between different companies (SNI). But how does the technology work? What are the associated controls, planning, and migration issues? This two-part presentation on Understanding Enterprise Extender will discuss these questions, and other issues, associated with deploying EE.

• Part one of this presentation focuses on various concepts and considerations behind EE. It includes topics such as:
• What is Enterprise Extender and what are its advantages?
• HPR - a brief overview
• The HPR path switch - What causes it and how can I control it?
• What is EE connection network?
• EE planning considerations

Understanding Enterprise Extender, Part 2 - Nuts and Bolts
This is the second part of the two-part presentation on Understanding Enterprise Extender.

Part two of this presentation focuses on the mechanisms and implementation details of EE. It includes topics such as:

• Three layers of inactivity timers
• EE enhancements in z/OS V1R5 and V1R6
• EE: What VTAM and TCP/IP definitions are required?
• Recent EE performance maintenance

z/OS Communications Server TCP/IP: Hints & Tips
z/OS Communications Server provides a rich set of features for enabling enterprise-class TCP/IP communications within your network. This presentation describes some of the little known or little used configuration parameters available for z/OS CS. Also described are common reported problems to z/OS CS level 2 service.

Using Traces for TCP/IP Throughput Performance Problems
Trace analysis can provide valuable insight when trying to determine the cause of TCP/IP throughput performance problems. But where do you start? And how do you sift through the potentially large volume of data to identify the actual problem? This presentation provides techniques for using traces to assist with resolving TCP/IP throughput-related performance problems.

APPN Configurations: Recommendations And Limitations
Migrating from subarea networking to APPN can be a daunting task. When the migration includes defining and configuring many different types of APPN nodes (such as Central Directory Servers, Dependent LU Requesters/Servers, Extended Border Nodes, Branch Extenders and Virtual Routing Nodes), the complexity increases significantly. This presentation describes the many types of APPN nodes that are available and that might be needed to complete a successful migration. It also describes configuration limitations imposed by the APPN architecture when various types of APPN nodes are in use. It provides recommendations on how to configure an APPN network to take full advantage of the latest and greatest APPN features and functions.

Searching In Mixed APPN and Subarea Networks
One key contributor to network performance is the implementation of effective searching algorithms. If you are familiar with subarea networking you are probably comfortable with the ADJSSCP tables used by VTAM for routing search requests. If you are familiar with APPN networking you are probably pleased with the dynamic nature of APPN searching. However, even an in-depth knowledge of both searching algorithms does not adequately prepare you for the complexities of controlling searches in a combined APPN/subarea network. This presentation gives you a detailed overview of the VTAM features that can be used to control and fine-tune the way network searches are performed by VTAM in combined APPN and subarea networks.

APPN LOGMODEs and Class Of Service
For most, moving from subarea networking to Advanced Peer-to-Peer Networking (APPN) is not a one-step process. There will likely be both APPN and subarea portions of the network for some time. During this period, it is essential that the network continue to perform predictably. One of the more common problems encountered during migration is LOGMODE and Class Of Service (COS) resolution. This paper provides a detailed overview of how LOGMODEs and COS names are resolved in subarea, APPN and mixed APPN/subarea networks.

SME versus DSME: A Comparison
When migrating an existing subarea network to Advanced Peer-to-Peer Networking, or APPN (including migrating SNA Network Interconnect, or SNI, connectivity to APPN Extended Border Node, or EBN, connectivity), customers who use the Session Management Exit (SME) quickly realize that the SME does not work the same way...or at all...in an APPN environment. Instead, they often discover that a Directory Services Management Exit (DSME) is needed in order to implement many of the functions previously performed by the SME. This presentation gives a side-by-side comparison of the functions, parameters lists and return codes supported by the SME and DSME. Session setup flow diagrams are also provided for several session configurations to demonstrate when (during session setup) and where (at which nodes) the INITAUTH (SME and DSME) and SECAUTH (SME only) functions are invoked.

EBN Searching in APPN/HPR Border Node Networks
A significant contributor to network performance is the implementation of effective searching algorithms. If your APPN network includes EBN connections to other APPN subnetworks, then your search algorithm must also take EBN searching into account. This presentation gives you a detailed description of how VTAM performs EBN searching and Alias name translation (which can affect EBN searching), and describes the VTAM Start Options and tables that can be used to control EBN Searching. In addition, sample adjacent cluster (ADJCLUST) tables are provided for every EBN in a complicated mixed APPN/subarea network to demonstrate the correct way to code ADJCLUST tables when BNDYN=NONE is used.