with SAP- Profile parameter gw/acl_mode = 1
Actual security advisories from SAP tell the customer to do so which is a good idea because it really increases security. With active gateway security all programs which want to register need to be declared in a kind of whitelist file.
Switch off gateway security by setting gw/acl_mode to 0 in transaction RZ10 or RZ11
Define both whitelist files „secinfo“ and „reginfo“ in the directory /usr/sap/<SID>/<INSTANCE>/data/ on the SAP System.
#VERSION=2
P TP=ICARO
#VERSION=2
P HOST=* USER=* TP=ICARO
in both cases TP=ICARO is exactly the Program-ID
as defined in bin\saprfc.ini
Definition and Activation of secinfo and reginfo can be done from inside SAP in transaction SMGW, no need to manually edit files in filesystem of SAP Server (Menu → Goto → Expert Functions → External Security → ….. )
Following some links for more information:
SAP Note 1480644: Activation of SAP Gateway Security
SAP Note 1305851: Overview about reg_info and sec_info
List of Parameters:
http://help.sap.com/saphelp_nw73/helpdata/en/48/ad76299eff35b7e10000000a42189d/content.htm
Explanation of Parameters:
http://help.sap.com/saphelp_nw73/helpdata/en/48/ad5b358bc96744e10000000a421937/content.htm