What is the purpose of DTS settings Legacy messaging support ?

Products

• CA Client Automation - IT Client Manager

Issue/Introduction

By default DTS Agent settings Legacy messaging support (LegacyCamSupport) is set to FALSE.

 

 

 

But if it is set to TRUE, the DTS transfer are made with a better rate.

 

 

Example on a test environment :

 

- When DSM/Data Transport Service (DTS)/Data Transport Agent Plugin/Legacy messaging support = FALSE (default value) is set on DOMAIN, the DTS staging of one package with size 114052 KBytes is made in about 46s (about 20.3 Mbits/s)

 

- When DSM/Data Transport Service (DTS)/Data Transport Agent Plugin/Legacy messaging support = TRUE  is set on DOMAIN, the DTS staging of the same package is made in about 7s (about 113.47 Mbits/s)

 

 

What is the purpose of parameter LegacyCamSupport ? And why DTS transfer is faster when it is set to TRUE ?

Environment

Client Automation - All Version

Resolution

LegacyCamSupport=TRUE is needed to support very old DTS Agent version (in very old version of Client Automation).

In recent Client Automation version, DTS Agent could use LegacyCamSupport=FALSE or LegacyCamSupport=TRUE settings.

 

With LegacyCamSupport=TRUE, DTS Agent sends CAM messages (to other DTS Agent) using direct CAM API.
 
 
With LegacyCamSupport= FALSE, DTS Agent sends CAM messages (to other DTS Agent) using the Session Messaging component.
Then Session Messaging component sends the message to CAM using CAM API but it does some encryption work before to secure the message and communication.

See following documentation for information about Session Messaging :
https://techdocs.broadcom.com/us/en/ca-enterprise-software/business-management/clarity-client-automation/14-5/implementing/fips-140-2-compliance/component-specific-cryptographic-use.html

Inter-node Communications [Session Messaging]
The session messaging component uses the TLS v1.0 protocol for inter-node communications. The chosen cipher suite will be selected by negotiation between the communicating nodes.
In some instances, the session messaging component uses the Key Transport Recipient Information structure as specified in the Cryptographic Message Syntax version 3 (CMS3) as specified in RFC3369.

 

It is why it takes more time with LegacyCamSupport= FALSE, because there is an added layer between DTS Agent and CAM : Session Messaging). It is useful to add some security in communication.
 
But if better performance is prefered (with less security in communication), LegacyCamSupport= TRUE on Domain Manager could be set. And Staging of SD Package with DTS transfer will be made with a better transfer rate.