v0.14.0-rc1
-----------

This pre-release contains two major new features, which should be considered experimental:

1. A modular forwarding and routing interface leveraging AAP 2.0:
    - AAP 2.0 is extended to allow applications to a) control and monitor outgoing links and b) perform forwarding decisions.
    - A shared-secret authentication + authorization procedure is implemented — applications intending to perform privileged actions need to specify an "administrative secret" passed to µD3TN at launch through an environment variable.
    - Moreover, two Python implementations of forwarding algorithms (Bundle Dispatch Modules, BDMs) are provided: a "compatibility BDM" implementing the well-known µD3TN forwarding approach and a simple static BDM based on a JSON routing table, intended to be used as a template for developing further BDMs.
2. A persistent storage feature based on SQLite, implemented as a CLA that represents a "storage-only bundle node" conceptionally:
    - This makes persistent storage a "next hop" to which bundles can be sent based on the decision of the used forwarding algorithm.
    - Releasing and/or dropping bundles from storage is controlled through a Protobuf-based API provided by the storage system on a dedicated endpoint.
    - Authorization is ensured via a flag set through AAP 2.0 if the administrative secret has been specified.

Additionally, the following changes are contained in this release:

- Graceful Termination of CLAs and the AAP 2.0 agent.
- License change: µD3TN as a whole is now provided unter the terms of the GNU AGPL. Some parts (e.g. the Python tools and some modules) will stay under the terms of the Apache 2 and BSD licenses.
- Extend the provided Nix tooling and integration.
- Allow FIB entries to specify a "direct dispatch" flag that causes the BPA to not consult the BDM, but directly forward bundles if their destination matches.
- Restructuring of the integrated next-hop forwarding approach so it is much more modular and can be fully disabled when using an external forwarding daemon (BDM).
- Move the Python tools to the `python-ud3tn-utils` package (links are provided in Git for backward-compatibility).
- Reliability and consistency improvements as well as general cleanups and bug fixes.

Note: The `aap_config.py` utility has been deprecated in favor of `aap2-config`, as it cannot set the flag required for secure operation. To continue using it, µD3TN needs to be launched with the `--allow-remote-config` commandline argument.

v0.13.0 "Maxwell"
-----------------

- Preview version of AAP 2.0 - a new Protobuf-based application interface, with Python tooling equivalent to the AAP 1.0 tools provided in tools/aap2; see doc/aap20.md
- Added a "data decoder" that can be built using `make data-decoder` and allows for inspecting captured bundles and CLA packets as well as running fuzz testing on the parsers
- Support for local node IDs not containing a terminating slash (dtn scheme) or a service number (ipn scheme)
- Moved all compile-time configuration options to config.mk with examples and defaults documented in config.mk.example
- Introduce configurable log levels - you can now select how verbose the output should be and debug log messages are disabled at compile time for more performant release builds
- Improved rate limiting for outgoing CLA connections that now also works when operating over SSH tunnels
- Improved interoperability testing, including tests against HDTN and DTN7-rs
- Improved static analysis, including automated execution of cppcheck
- Added a Nix Flake definition and a Nix-based development environment
- Automated testing on macOS and FreeBSD
- Pinning of Python dependencies to ensure a deterministic Python environment
- Several small bug fixes, more tests, and general improvements

v0.12.0 "Loki"
--------------

- macOS support
- FreeBSD support
- ARM and ARM-64 support with Clang and GCC compilers
- improved interoperability testing with ION 3.7 and 4.1 plus IONe and added documentation for it
- substantial improvements of the test toolchain, including a Docker image with all dependencies, static analysis, and support for sanitizers
- aap_echo and aap_ping utilities plus a built-in echo agent to realize basic reachability and latency tests
- transparent delivery of the bundle creation timestamp to applications via the AAP bundle identifier
- CBHE (RFC 6260) support for incoming BPv6 bundles
- improved IPv6 support
- removal of the unused STM32 target
- lots of further bug fixes and improvements, internal simplifications, and cleanups

v0.11.0 "Kerwan"
----------------

- Implement Bundle-in-Bundle Encapsulation convergence layer (in this initial version without custody transfer features)
- Add proper support for the `ipn:` EID scheme (BPv7 and BPv6 without CBHE)
- Enable contacts with "infinite" capacity (long-running, high-data-rate contacts where the capacity does not matter anymore are considered to allow for infinite bundles)
- Add a simple bundle forwarding stress test
- Make the remote configuration capability a command line flag
- Fix build of `libud3tn.so` shared library
- Fix EID validation being too permissive
- Update license: µD3TN is now additionally provided under the Apache 2.0 license

v0.10.0 "Juliet"
----------------

- Disallow remote configuration: Config bundles are only accepted via AAP
- BPv7 compatibility:
    - Millisecond-based timestamps
    - Support of Bundle Age extension block
    - Drop previous node block (unsupported by µD3TN, but has to be removed according to standard)
- Add a Docker image
- Use working directory instead of `/tmp` for AAP socket by default
- Make it possible to use an RX read timeout for unreliable connections
- Increase maximum number of fragments
- Bugfixes and documentation improvements (e.g., README, quick start guide)

v0.9.0 "Imbrium"
----------------

The changes between µPCN v0.8.0 and this release include:

- GitLab publication and renaming to µD3TN
- Public Continuous Integration pipeline
- Separation of Python modules into packages pyD3TN and ud3tn-utils
- Minor bugfixes and documentation improvements

µPCN v0.8.0 "Himalayas"
-----------------------

- Updated license information
- Updated command line parser
- Replaced TCP socket used for AAP by a UNIX domain socket
- Support for BPv7 draft version 22
- ION interopability test for BPv7
- Updated documentation

µPCN v0.7.0 "Galaxius"
----------------------

- Modified the overall architecture of the communication subsystem
- MTCP implementation according to https://tools.ietf.org/html/draft-ietf-dtn-mtcpcl-00
- CLA parameters plus parts of the µPCN configration can be provided as CLI parameters
- Added support for BPv7 draft version 17 (https://tools.ietf.org/html/draft-ietf-dtn-bpbis-17)
- IPv6 support for CLAs
- Removed neighbor discovery approach
- Support for a DTN application API based on an Application Agent Protocol (AAP)
- Major refactoring of build system
- New packet format of STM32 USB CLA made compatible with MTCP
- Replacement of integration tests by new pyupcn-based toolchain
- ION interopability test

µPCN v0.6.0 "Falsaron"
----------------------

In this release, an updated version of the Bundle Protocol version 7 draft specification (draft version 10) is available. Furthermore, the transmission and receive subsystem has been restructured to support various convergence layers.

- Update of the BP-bis implementation to RFC draft version 10 (https://tools.ietf.org/html/draft-ietf-dtn-bpbis-10)
- Integration of the TCPCL convergence layer
- Support for the Space Packet Protocol (SPP)
- Partially project restructuring
- Various bugfixes

µPCN v0.5.0 "Elysium"
---------------------

The main goal of this release was to include support for the Bundle protocol version 7 draft specification for testing and evaluation purposes.

- Implementation of the BP-bis draft specification defined by https://tools.ietf.org/html/draft-ietf-dtn-bpbis-06
- Fixing various bugs after running fuzzing tests
- Support for FreeRTOS 9

µPCN v0.4.0 "Denali"
--------------------

The main goal of this release was to port µPCN to the POSIX interface.

- Restructured µPCN to make it work against a generic, platform independent interface
- Add POSIX support
- Improved Bundle serialization / throughput
- Extended test tools
- Several bug fixes

µPCN v0.3.0 "Caloris"
---------------------

The main goal of this release was to integrate a contact prediction approach.

- Integrated new version of the Ring Road Neighbor Discovery (RRND)
- Implemented enhanced contact prediction approach based on RRND and SGP4
- Restructured GroundStationTask - one Task cares for several ground stations
- Provided static code analysis (make clang-check)
- Extended test tools
- Several bug fixes plus performance improvements

µPCN v0.2.0 "Boösaule"
----------------------

This release focused on stabilizing the initial release.

- Bugfixing, restructuring and cleanup
- Added trust handling to the ContactManager
- Extended test infrastructure (e.g. Denial-of-Service test is available)
- Implemented zero-copy-approach by using a pointer lookup table for often used data (e.g. EIDs)
- Increased configurability of µPCN
- Improved error handling

µPCN v0.1.0 "Aeolis"
--------------------

- Initial release
- RFC 5050 conformant bundle protocol version 6 implementation
- Two-stage routing approach with decision optimization between contacts
- DTN IP Neighbor Discovery (IPND draft 02) with extensions for RX/TX bitrate,
  AX.25 CLA address and cookie to protect against DoS attacks
- Unit test suite and integrated debugging tools (mem management, logging, CPU)
- Test setup for running pre-defined test scenarios with TCP server
