This release contains an integrated prototype of the Bundle Security Library (BSL).

The native BPSec implementation, available in ION since ION 4.1.3s, remains the default implementation. Users can experiment with BSL by using the --enable-bsl switch in the configure script. BSL is now available on the default integration branch.

For detailed instruction, please see documentation here: https://ion-dtn.readthedocs.io/en/ion-open-source-4.2.0-a.1/BSL-Build-Install-Guide/