The Database as a Networked Server - Implementing Database Security and Auditing - page 75

Figure 3.8
Figure 3.8: (a)
Setting the TCP/IP
port; (b) Setting the
named pipe.

can click on the Properties button to select protocol-specific attributes. For
example, if you click the Properties button for TCP/IP, you can change the
default port of 1433 (Figure 3.8(a)), and if you click the Properties button
when selecting Named Pipes, you can change the default pipe name (Fig-
ure 3.8(b)). When you install a client you have an equivalent Client Net-
work Utility that allows you to configure which protocols the client will be
using (and the order by which a client netlib is used if more than one
option is available).

3.4.2 DB2 networking layers

DB2 UDB's networking options include TCP/IP, IPX/SPX, Named Pipes,
NetBIOS, and APPC. Advanced Program-to-Program (APPC) is an
implementation of the IBM SNA/SDLC LU6.2 protocol that allows
interconnected systems to communicate and share the processing of pro-
grams; if you haven't had the need to know what this means until now,
you probably will never have to—it is a construct that is mainly relevant
to the mainframe world. Not all options are available for all platforms; for
example, APPC is available for Windows clients when accessing a Solaris
server but not when accessing a Linux server. DB2 communication
options are usually defined automatically when DB2 is installed—it senses
what communication protocols are available on the host and adjusts the
definitions appropriately.
If you would like to reduce the number of installed protocols, you can
use the Control Center. Use the left tree view to navigate to the instance
you wish to configure and then right-click and select Setup Communica-
tions. This will allow you to choose which networking libraries are enabled
(see Figure 3.9) and which are not, as well as set up properties for each com-
munication type (e.g., changing the port from the default 50000 for TCP/
IP communications).