Introduction › Network Configuration

Network Configuration

A CA IDMS DDS network consists of multiple nodes connected by the SVC or a telecommunications line, as follows:

• SVC—The SVC connects two or more nodes residing in a single machine, as shown in the following illustration.

  Data and application requests are transferred between the two nodes through the SVC.

  

• Telecommunications line—A telecommunications line connects two nodes residing in different machines at remote sites or two nodes in the same machine. Data and application requests are transferred between the two nodes across the line by the telecommunications access method. The telecommunications lines between nodes can be any supported by the Common Communications Interface (CCI), TCP/IP, or VTAM.
  • CCI—For a list of supported communications access methods, see the CA Common Services for z/OS documentation.
  • TCP/IP—TCP/IP controls communication between machines. When TCP/IP is used to connect two CA IDMS DDS nodes, communication is controlled by TCP/IP.
  • VTAM—VTAM controls communications between machines. When VTAM is used to connect two CA IDMS DDS nodes, communication is controlled by VTAM.

Use of CCI, TCP/IP, or VTAM in a CA IDMS DDS environment is illustrated as follows:

Direct and indirect connections

In a network, a node can be connected directly (by way of SVC or a teleprocessing line) to any number of other nodes. If two nodes are connected directly, communication between them takes place by way of this direct connection. If two nodes are not directly connected, communication between them takes place by way of one or more nodes that are directly connected to the host and target nodes. The following illustration shows a sample CA IDMS DDS network.

The nodes in New York and Boston can communicate by way of a direct connection. However, node SYSTEM06 in Los Angeles would communicate with node SYSTEM01 in Boston by way of SYSTEM05.

Configuring the network

CA IDMS DDS network configuration is defined through DC/UCF system generation procedures. In addition to standard system generation entries, the system generation of each system that participates in the network includes entries to:

• Identify the node
• Define the node's direct connections to other nodes
• Name the databases controlled by the node

The user can obtain reports on the generation of nodes through the Data Dictionary Reporter (DDR).

Note: For more information about CA IDMS DDS system generation, see Chapter 3, "CA IDMS DDS System Generation".

Changing configuration

Facilities are available that allow the user to alter the network configuration as necessary.

Note: For more information about managing the network, see Chapter 4, "CA IDMS DDS System Operations".

Path selection

Within a network, the CA IDMS DDS controls the selection of the path along which application requests are transferred between nodes. Path selection and global and local databases are discussed in Chapter 2, "Network Design Considerations".

The remainder of this manual provides information essential to the design and implementation of a CA IDMS DDS network.