Introducing the BEA Tuxedo TOP END Domain Gateway

This topic includes the following sections:

• What Is the TOP END Domain Gateway?

• Understanding How the TOP END Domain Gateway Works

 

---

What Is the TOP END Domain Gateway?

BEA Tuxedo Domains provide a framework for interoperability between the domains of a business that require administrative autonomy but allow sharing of services and data. The TOP END Domain Gateway (TEDG) extends the BEA Tuxedo Domains concept to include BEA TOP END interoperability. The TEDG supports transactional message passing and queuing between the BEA TOP END and BEA Tuxedo systems.

Features of the TOP END Domain Gateway

The TOP END Domain Gateway provides the following features:

• Message Passing

• Queue Processing

• Transactional Support

• Security

Message Passing

Message passing provides bi-directional communication between BEA TOP END and BEA Tuxedo user components. The primary message passing capabilities are:

• BEA TOP END client applications can initiate messages that are transparently delivered to BEA Tuxedo servers.

• BEA Tuxedo client applications can initiate messages that are transparently delivered to BEA TOP END servers.

• Request/response mode is supported in both directions.

• BEA TOP END pseudo-conversational mode is mapped to BEA Tuxedo conversational mode.

Queue Processing

Queue processing capabilities include:

• BEA TOP END application components can enqueue items onto BEA Tuxedo /Q queues.

• BEA Tuxedo Application-to-Transaction Monitor Interface (ATMI) applications can enqueue items onto BEA TOP END RTQ queues.

• Processing of requests from the queues is handled by the system that hosts the queue.

  • Requests enqueued to BEA TOP END RTQ queues are processed by the RTQ subsystem. BEA TOP END RTQ does not support an explicit dequeue concept.

  • Requests enqueued to BEA Tuxedo /Q queues may be explicitly dequeued by an application or processed via TMQFORWARD.

Transactional Support

Transactional support allows global transactions to span BEA Tuxedo systems and BEA TOP END systems. That is, if a global transaction is begun in a component of one product and subsequent messages or enqueuing operations are sent to components in another product, the scope of the transaction includes work performed by components in the second product.

Security

The TOP END Domain Gateway provides the following security methods for communications:

• Authentication—each domain performs local authentication of clients.

• Authorization—existing BEA Tuxedo and Domains authorization is supported in the TOP END Domain Gateway.

• Encryption—the link between the TOP END Domain Gateway and the BEA TOP END system is optionally encrypted to ensure privacy.

See Also

• Interconnecting Systems with the TOP END Domain Gateway

• "What Is the BEA Tuxedo Domains Component?" on page 1-1 in Using the BEA Tuxedo Domains Component

 

---

Understanding How the TOP END Domain Gateway Works

This topic includes the following sections:

• BEA Tuxedo and BEA TOP END Terminology

• BEA Tuxedo Architecture Overview

• BEA TOP END Architecture Overview

• How the TEDG Works

 

---

BEA Tuxedo and BEA TOP END Terminology

While BEA Tuxedo and BEA TOP END offer similar capabilities, the terminology used by each product family is different. The following table provides a comparison of BEA TOP END and BEA Tuxedo terminology.

Table 1-1 Comparison of BEA Tuxedo and BEA TOP END Terms  

BEA Tuxedo	BEA TOP END	Description
Domain	System	Collection of servers (programs) and other components that are deployed on a network of one or more nodes and administered together.
Bridge	Network Interface (NI)	Process that manages internode communication within a domain or system.
Bulletin Board Liaison (BBL)	Node Manager (NM)	A set of one or more processes that manage a domain or system on a run-time node.
Workstation Handler (WSH)	Network Agent (NA)	Process that handles service requests from remote clients.
/Q	RTQ	A set of reliable queuing facilities that allow messages to be passed using queues.
ATMI	CSI	Application programming interfaces for the BEA Tuxedo and BEA TOP END systems, respectively.
Workstation client	Remote client	Client process running on a remote site.

 

TEDG Terminology

The following table summarizes common terminology used in reference to the TEDG.

This Term . . .	Refers to . . .
Remote domains	BEA TOP END systems accessed via the TEDG.
Remote domain DOMAINID	BEA Tuxedo user ID for requests made to the BEA Tuxedo system by the BEA TOP END system.
Local domains	BEA Tuxedo domains accessed via the TEDG. The term "local domains" can also be used to refer to a subset of the domain.
Local domain DOMAINID	BEA TOP END user ID for requests made to the BEA TOP END system by the BEA Tuxedo system.
Imported services	Remote services imported from a BEA TOP END system.
Exported services	Local services exported to a BEA TOP END system.

 

Reference Manual Notation

TEDG users should keep in mind that references to entries in the BEA TOP END Programmer's Reference Manual are marked by a "T" after the section number included in the reference. For example, the tp_intro(1T) entry can be found in the BEA TOP END Programmer's Reference Manual. Entries referenced without a "T" after the section number (such as tmboot (1)) can be found in the appropriate section of the BEA Tuxedo reference manual:

• BEA Tuxedo Command Reference

• BEA Tuxedo ATMI C Function Reference

• BEA Tuxedo ATMI COBOL Function Reference

• BEA Tuxedo ATMI FML Function Reference

• File Formats, Data Descriptions, MIBs, and System Processes Reference

 

---

BEA Tuxedo Architecture Overview

The BEA Tuxedo system uses the concept of a domain to define a collection of nodes (or machines) involved in an administratively autonomous application. A system administrator uses two files, UBBCONFIG and DMCONFIG, to configure a BEA Tuxedo domain.

A distributed-domain configuration consists of one or more business applications running on multiple machines. Although it contains multiple machines, this type of configuration is considered a single domain because it is administered centrally as a single entity. The following diagram shows the basic parts of a configuration distributed across multiple machines.

Figure 1-1 BEA Tuxedo Distributed Configuration

 

The primary components of a distributed configuration are:

• Client applications—executable programs that may request services through the BEA Tuxedo system.

• Server applications—executable programs that offer named services through the BEA Tuxedo system.

• ATMI—the application programming interface (API) for the BEA Tuxedo system.

• BEA Tuxedo Services—services and/or capabilities common to the BEA Tuxedo system infrastructure for developing and administering applications. The application processing services available to developers include: transactions, messaging paradigms, type validation, load balancing, data-dependent routing, service prioritization, data encoding, marshalling, compression, and reliable queuing. The administrative services include: distributed transaction processing, security management, service naming, distributed application administration, centralized application configuration, dynamic reconfiguration, and domains partitioning.

• Bulletin Board—a shared memory segment that holds configuration and dynamic information for the system. It is available to all BEA Tuxedo processes.

• Bulletin Board Liaison (BBL)—a BEA Tuxedo administrative process that monitors the data stored in the bulletin board and any changes made to it.

• Distinguished Bulletin Board Liaison (DBBL)—a process dedicated to making sure that the BBL server on each machine is alive and functioning correctly. This server runs on the master machine of a domain and communicates directly with all administration facilities.

• Bridges—BEA Tuxedo supplied servers that send and receive service requests between machines, and route them to local servers.

A multiple-domain configuration consists of two or more domains that communicate with each other through a gateway process in each domain. This gateway process provides bidirectional transaction control, and administrative tools that allow the configuration of the information required for interoperability of the local application with other domains. This configuration information includes the identification of a set of exported services, imported services, addressing, and access control. For an illustration of a multiple-domain configuration, see "BEA Tuxedo ATMI Infrastructure" on page 3-2 in Introducing BEA Tuxedo ATMI.

See Also

• Interconnecting Systems with the TOP END Domain Gateway

• "Basic Architecture of the BEA Tuxedo ATMI Environment" on page 2-2 in Introducing BEA Tuxedo ATMI

 

---

BEA TOP END Architecture Overview

The basic architecture of a BEA TOP END system is shown in the following figure.

Figure 1-2 Basic BEA TOP END System Architecture

 

As shown in the figure, a BEA TOP END system consists of one or more nodes. A basic node consists of a client, a node manager, and a server.

• A node may have one or more BEA TOP END systems.

• Each BEA TOP END system on a node has one node manager component.

An Application Component consists of the following:

• Application (AP)

• Resource Manager (RM)

• Transaction Manager (TM)

• Client/Server Interaction API (CSI)

The network interface (NI) is an optional component in a BEA TOP END system. An NI is not required for single-node systems. The Network Interface:

• Enables internode communication between components

• Provides optional internode message security through Kerberos routines

See Also

• Interconnecting Systems with the TOP END Domain Gateway

• BEA TOP END System Design Guide

 

---

How the TEDG Works

The TOP END Domain Gateway (TEDG) provides interoperability between BEA TOP END systems and BEA Tuxedo Domains. The TEDG consists of two parts: a gateway administrative server and a gateway process.

Part	Description
Gateway administrative server (GWADM)	The gateway group administrative server that registers with the DMADM server to obtain configuration information used by the gateway group.
Gateway process (GWTOPEND)	The gateway process that provides connectivity to remote BEA TOP END systems.

 

Each GWADM/GWTOPEND pair represents an instance of the TEDG. Multiple instances can be configured by specifying multiple GWADM/GWTOPEND pairs, one pair per BEA Tuxedo group.

• A TEDG connects to one or more nodes of a single BEA TOP END system. Connections must be made to each node that provides services required by a BEA Tuxedo application and to each node that uses BEA Tuxedo services. A TEDG can provide access to a BEA Tuxedo application only for connected BEA TOP END nodes.

• A TEDG can provide access to a BEA TOP END system for all BEA Tuxedo nodes in the domain or other connected domains.

• Multiple TEDG gateways may be configured in a domain or on a node to connect to different BEA TOP END systems.

• Multiple TEDG gateways may be configured to connect to a single BEA TOP END system as long as no more than one connection exists between any pair of nodes consisting of a TEDG node and a BEA TOP END node.

• The BEA TOP END system can communicate with multiple BEA Tuxedo domains as long as no more than one connection exists between any pair of nodes consisting of a TEDG node and a BEA TOP END node.

• Each TEDG is defined as a local domain in the DMCONFIG file that defines all gateways for a domain.

The following illustration shows how the TEDG connects a BEA TOP END system and a BEA Tuxedo domain.

Figure 1-3 Connecting Systems with the TOP END Domain Gateway

 

How a BEA Tuxedo User Views the TEDG

From the perspective of a BEA Tuxedo system user, the TEDG:

• Is controlled by the BEA Tuxedo system.

• Appears as a set of BEA Tuxedo services to the BEA Tuxedo client program.

• Allows BEA Tuxedo client programs to make calls to BEA TOP END services as if those services were part of the local domain.

• Maps requests from the BEA Tuxedo client programs to the appropriate BEA TOP END services, forwards those requests for processing, and then returns the results as required.

• Is viewed by a BEA Tuxedo client as a BEA Tuxedo server, and by a BEA Tuxedo server as a BEA Tuxedo client.

How a BEA TOP END User Views the TEDG

From the perspective of a BEA TOP END system user, the TEDG:

• Appears as another Network Interface (NI) in the BEA TOP END system.

• Allows BEA TOP END clients to access BEA Tuxedo services.

• Maps these requests from the BEA TOP END client programs to the appropriate BEA Tuxedo services, forwards them for processing, and then returns the results as required.

• Is viewed by a BEA TOP END client as a BEA TOP END server, and by a BEA TOP END server as a BEA TOP END client.

See Also

• Interconnecting Systems with the TOP END Domain Gateway