About simultaneous transfers

This section addresses the question "What is the maximum number of transfers possible for my Transfer CFT?" and describes how to optimize the number of parallel transfers, the number of transfer sessions, and how parameter dependencies affect transfer rates.

We begin with basic checks and recommendations:

License key

The first factor that determines the maximum number of simultaneous transfers is the number defined by the license key, so begin by checking the license key limits.

How many transfers does my license key allow?

Check the Transfer CFT log, which displays the maximum number of transfers. The "n" value n in the following example is the authorized limit.



CFT Windows

Version 3.1.3 20150224

(C) Copyright AXWAY 1989-2014

====> Starting Session on 24/04/2015 Time is 09:52:12

Parameters file :C:\Axwaycft313sp1\Transf..CFT\runtime\data\cftparm


CFTI18I+On 999 authorized simultaneous transfer(s), n is(are) active


How can I increase the license key limit?

To increase the license key limit contact your Axway sales representative, or visit away.com to find your regional representative.

Types of parallel transfer parameters

While several parameters affect the maximum number of simultaneous transfers, and by extension transfer performance, there are two basic types of parameters that manage parallel transfers:

  • Connection parameters
  • Session parameters
Note Some simultaneous transfer parameters values are platform dependent.


You can modify the following using either the Transfer CFT UI (restart when prompted) or CFTUTIL.

When using CFTUTIL to modify the parameters:

  1. CFTUTIL CFTEXT FOUT=<config_file>
  2. Modify the value in the <config_file> file.

Connection parameters


This parameter is the most basic parameter to define the maximum number of transfers. The MAXTRANS value sets the physical limit for the product independently of the limit set by the software key. MAXTRANS values


Related UCONF values:

  • cft.run.maxtrans:The last MAXTRANS value used by Transfer CFT (information only)
  • cft.server.maxtrans: This parameter can override the MAXTRANS of the CFTPARM object

This parameter determines the number of connection session calls for a network resource. Usually when you have only one CFTNET is to set the MAXCNX  to the same value as MAXTRANS, regardless of the network used. See the Examples for exceptions.

Ensure that MAXCNX from CFTNET is less than or equal to the CFTPARM capability. MAXCNX values


Related UCONF value:

  • cft.server.max_session: Maximum number of simultaneous sessions

This parameter controls the number of CFTTFIL processing that can run. Since more processes use more machine memory, remember when increasing MAXTASK to take available resources into account. MAXTASK values

Note There is a one to one relationship between a transfer and its task. That is, the task cannot be shared, so it is recommended to set the MAXTASK to less than or equal to MAXTRANS.

This parameter defines the number of transfers managed per task, and operates similar to load balancing between tasks. TRANTASK values


The following parameter values creates 2 file access tasks, each handling 4 transfers. Transfers 1 through 8 are assigned to the two tasks (as there are four transfers for each task). All new concurrent transfers are put on hold until resources become available.



Session parameters

This section provides examples concerning the session parameters.

When defining flow exchanges with a partner, it is recommended to check the partner's number of in, out or inout connections and keep these values in mind during configuration. That means that for each Transfer CFT partner, you should specify in the CFTTCP command the parameters CNXIN, CNXOUT, and CNXINOUT parameters relative to the CFTPART (having the same ID).


[cnxin = { 2 | n }]

This parameter defines the maximum number of sessions for incoming connections.

The value should be less than or equal to the MAXCNX and MAXTRANS values.

CFTTCP ID =<partner1_id>, HOST=<partner1_URL>, CNXIN=n, ...

[cnxout = { 2 | n }]

Maximum number of sessions for outgoing connections.

CFTTCP ID =<partner1_id>, HOST=<partner1_URL>, CNXOUT=n, ...

[cnxinout = { 2 | n }]

Maximum number of communication sessions (less than or equal to the MAXCNX and MAXTRANS values).

CFTTCP ID =<partner1_id>, HOST=<partner1_URL>, CNXINOUT=n, ...

Optimization tips

The following recommendations can help you set basic parameters. The examples in the Example scenarios and output section explain and reinforce these recommendations.

  • Set the MAXCNX value in CFTNET to less than or equal to the MAXTRANS value in CFTPARM.
  • Set the CNXIN plus CNXOUT (the combined value of the two) to less than or equal to the CNXINOUT value.
  • Set the CNXINOUT value to less than or equal to the MAXCNX in CFTNET.
  • Set the CNXINOUT value o less than or equal to CNXINOUT value of the partner (or equivalent value if the partner is not a Transfer CFT).
  • The values for CNXIN, CNXOUT or CNXINOUT should be less than or equal to the MAXCNX in CFTNET, which should be less than or equal to MAXTRANS in CFTPARM.
Note The above are generic best practices. Please also take into account factors such as the operating system, the memory allotted for the Transfer CFT application, and other local resource considerations.

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