Connecting systems with TCP/IP
Transmission Control Protocol/Internet Protocol (TCP/IP) is a standard communication protocol for network communications. Previous versions of DB2® supported TCP/IP requesters, although additional software and configuration was required.
About this task
The domain name (IP address) and port number (service name) uniquely identify a DB2 subsystem in the TCP/IP network. The domain name and the server port number (service name) of the database server must be defined in the communications database (CDB) at a requesting DB2 so that the DB2 subsystem can connect to a remote location. If you use a port number in the CDB to access a remote DB2 location, the port number must be defined to TCP/IP. The domain name must be defined to the TCP/IP host so that a DB2 subsystem can accept connections from remote locations. Port numbers are never used by a DB2 subsystem that accepts connections. Optionally, you can protect the port number that DB2 uses when acting as a server within TCP/IP from being used by any other task or job in the subsystem. When DDF is started, the DB2 subsystem binds itself to its designed port.
- TCP/IP terminology
DB2 uses some terms that are specific to communications. - Enabling TCP/IP communication
To enable TCP⁄IP communication between DRDA partners and DB2, you must complete some tasks such as preparing the Language Environment® run time library. - TCP/IP limitations
TCP/IP
does not have the built-in security features that SNA has, such as
SNA partner LU verification.
- Initializing a TCP stack for use with a VIPA
During initialization of a TCP stack for use with a virtual IP address (VIPA), the PROFILE.TCPIP configuration should contain the HOME list with the VIPA. The HOME list should be followed by the PRIMARYINTERFACE statement pointing at the appropriate VIPA that is to be used by DB2. - Initializing a TCP stack for use with both IPv4 and IPv6 addresses
To use both IPv4 and IPv6 addresses, DB2 requires TCP/IP dual-mode stack support. Dual-mode stack support allows IPv4 address communication with IPv4 partners, and IPv6 address communication with IPv6 partners. - Two-phase commit for TCP/IP clients
DB2 supports two types of two-phase commit for TCP/IP clients. - Multiple TCP/IP stacks and DB2
Running multiple TCP/IP stacks does not provide performance advantages over a single TCP/IP stack, which can provide high levels of scalability and performance by itself. Running multiple stacks requires more private and ECSA memory consumption and some additional processor consumption. It is also a much more complicated environment to manage from an administrative perspective. - Specifying security requirements
When you set up systems to communicate through TCP/IP, you must specify security requirements.