The system default QOP is defined by the TdgssLibraryConfigFile.xml.
You can configure a stronger encryption algorithm for the DEFAULT QOP. See QOP Configuration Options.
<!-- Low, Medium and High QOP values are all set to "Default"
unless the Low, Medium and High values are explicitly set
in TdgssUserConfigFile.xml -->
<!-- To update security uncomment one or more QOPs and edit. -->
<!-- DEFAULT QOP
<MechQop Value="Default">
AES-K128_GCM_PKCS5Padding_SHA2_DH-K2048
AES-K128_CBC_PKCS5Padding_SHA1_DH-K2048
AES-K192_GCM_PKCS5Padding_SHA2_DH-K2048
AES-K192_CBC_PKCS5Padding_SHA1_DH-K2048
AES-K256_GCM_PKCS5Padding_SHA2_DH-K2048
AES-K256_CBC_PKCS5Padding_SHA1_DH-K2048
</MechQop>
-->