IBM AS/400 Hardware User Manual Download

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Change the request/response unit size to a lower value for the large transfer. This parameter setting
optimizes response time at the expense of large transfer performance.

Reduce the pacing values for the large transfer to slow it down, which allows the interactive users more
windows for getting on the line.

Note:

The overall central processing unit time increases for the large transfer.

For more information about AS/400 communications, see the Communications Configuration

book.

Performance considerations for AnyNet communications

AnyNet communications is a good performance factor for you to consider. It is more expensive to use than
any of the OS/400 protocols because you spend twice as much to run two protocols.

To optimize AnyNet performance, consider the following:

For send and receive pairs, the most efficient use of an interface is with its own protocol stack. That is,
intersystem communications function (ICF) and common programming interface communications (CPI
Communications) perform the best with advanced program-to-program communications (APPC). There
is additional CPU time when the crossover between the protocols processes.

Each communications interface performs differently depending on the scenario. ICF and CPI
Communications perform the best with APPC.

Note:

An alternative to AnyNet communications is to have SNA and TCP/IP running parallel or over the
same lines in your network. Hence, performance implications can be surpassed by not using
AnyNet.

For more information about AnyNet/400 sockets, see the book Sockets Programming

Setting up the AnyNet environment

AnyNet/400 is an AnyNet family product. These products allow you to use application programs that are
written for a certain communications protocol but also run over non-native communications protocols
without changing (or even re-compiling) the application program. The choice of the destination address
controls whether the request is sent over the native protocols or through the AnyNet code and on to a
non-native protocol.

To configure Transmission Control Protocol/Internet Protocol (TCP/IP) over advanced program-to-program
communications (APPC), you need to take two basic actions:
1. Identify the set of IP addresses to route over the SNA network.
2. Tell the system how to convert the IP address to the SNA format.

For more information about APPC Over TCP/IP Configuration, see the APPC Programming book.

For more information about IPX Support, see the Internetwork Packet Exchange (IPX) Support.

For related information about AnyNet, see:

“AnyNet communications for the AS/400 system”
“Performance considerations for AnyNet communications”

AnyNet communications for the AS/400 system

AnyNet

is an IBM implementation of the Multiprotocol Transport Networking (MPTN) architecture, such as

AnyNet/2 and AnyNet/Multiple Virtual Storage (MVS). AnyNet capability allows applications and associated
services that use application programming interfaces, such as sockets, intersystem communications
function (ICF), or CPI Communications, the flexibility to use alternative network protocols, such as
Systems Network Architecture (SNA) or TCP/IP. AnyNet is a family of products that allow applications that

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