IBM CDI5UG1107 manual CLASSn, Compress *NO*YES*EXTX\xx\C\cc, Crc*Initparms*Netmap*Off*On

30IBM Sterling Connect:Direct for i5/OS User’s Guide

CLASS(n)

determines the node-to-node session on which an operation can execute. The CLASS is a number in the range of 1–255. If you do not specify the CLASS parameter, it defaults to the number of maximum sessions defined in the mode description for the communications environment.

Note: The CLASS parameter is not used by Sterling Connect:Direct for i5/OS.

COMPRESS (*NO*YES*EXTX\xx\C\cc\)

specifies that the data is to be compressed, which reduces the amount of data transmitted as the file is copied from one node to another. The file is automatically decompressed at the destination.

Note: Compression is CPU-intensive, and its effectiveness depends on the data and line speed. Only use it if it benefits the installation.

You should specify the primary compression character for text data or single-character repetitive data. Extended compression generally offers improved compression for all types of data.

*NO specifies no compression.

*YES enables compression. If *YES is specified, the default primary compression character is PRIMEchar=X\40\ (hex 40=“ ”).

If you specify *YES, Sterling Connect:Direct compresses the data transmitted based on the following rules:

™Repetitive occurrences (ranging from 2–63) of the primary compression character are compressed to one byte.

™Repetitive occurrences (ranging from 3–63) of any other character are compressed to two bytes.

*EXT specifies that extended compression is used to search for repetitive strings of characters in data and compress them to codes that are transmitted and converted back to the original string during decompression. Use this parameter when the line transmission speeds are limited, the CPU is available, and the data is repetitive.

X\xx\ enables compression, where xx is the hexadecimal representation of the value to be used for the primary compression character.

C\cc\ enables compression, where cc is the character representation of the value to be used for the primary compression character.

CRC(*INITPARMS*NETMAP*OFF*ON)

Determines whether node and Process statement overrides for Cyclic Redundancy Check (CRC) are allowed. If this value is set to *OFF, setting overrides for CRC checking will be ignored. The default value is *INITPARMS.

*INITPARMS specifies that the CRC setting is determined by the value for the initialization parameter TCP.CRC.

*NETMAP specifies that the CRC setting is determined by the value for the NETMAP parameter, Cyclic Redundancy Check. The value for the initialization parameter TCP.CRC must be set to *ON and the value for the initialization parameter TCP.CRC.OVERRIDE must be set to *YES.

*OFF specifies that CRC is disabled.

*ON specifies that CRC is enabled.

ECTUNING(ecclevel,ecwinsize,ecmlevel)

ECCLEVEL specifies the extended compression level, which affects how much CPU the extended compression routines use. Higher compression levels use more CPU but achieve greater compression. The valid values for this subparameter are 1–9, inclusive. The default value is *INITPARMS.