diff --git a/LICENSE.md b/LICENSE.md
index 0a2e8d7..cad616a 100644
--- a/LICENSE.md
+++ b/LICENSE.md
@@ -1,69 +1,174 @@
-Copyright (c) <2025> CyberMages LLC
+# Apache License
+Version 2.0, January 2004
+<http://www.apache.org/licenses/>
 
-Redistribution and use in source and binary forms, with or
-without modification, are permitted provided that the
-following conditions are met:
+## TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
 
-1. Redistributions of source code must retain the above
-   copyright notice, this list of conditions and the
-   following disclaimer.
+### 1. Definitions.
 
-2. Redistributions in binary form must reproduce the above
-   copyright notice, this list of conditions and the
-   following disclaimer in the documentation and/or other
-   materials provided with the distribution.
+**"License"** shall mean the terms and conditions for use, reproduction,
+and distribution as defined by Sections 1 through 9 of this document.
 
-Subject to the terms and conditions of this license, each
-copyright holder and contributor hereby grants to those
-receiving rights under this license a perpetual,
-worldwide, non-exclusive, no-charge, royalty-free,
-irrevocable (except for failure to satisfy the conditions
-of this license) patent license to make, have made, use,
-offer to sell, sell, import, and otherwise transfer this
-software, where such license applies only to those patent
-claims, already acquired or hereafter acquired, licensable
-by such copyright holder or contributor that are
-necessarily infringed by:
+**"Licensor"** shall mean the copyright owner or entity authorized by
+the copyright owner that is granting the License.
 
-   (a) their Contribution(s) (the licensed copyrights of
-       copyright holders and non-copyrightable additions
-       of contributors, in source or binary form) alone;
+**"Legal Entity"** shall mean the union of the acting entity and all
+other entities that control, are controlled by, or are under common
+control with that entity. For the purposes of this definition,
+"control" means (i) the power, direct or indirect, to cause the
+direction or management of such entity, whether by contract or
+otherwise, or (ii) ownership of fifty percent (50%) or more of the
+outstanding shares, or (iii) beneficial ownership of such entity.
 
-   -- or --
+**"You" (or "Your")** shall mean an individual or Legal Entity exercising
+permissions granted by this License.
 
-   (b) combination of their Contribution(s) with the work
-       of authorship to which such Contribution(s) was
-       added by such copyright holder or contributor, if,
-       at the time the Contribution is added, such
-       addition causes such combination to be necessarily
-       infringed. The patent license shall not apply to
-       any other combinations which include the
-       Contribution.
+**"Source" form** shall mean the preferred form for making modifications,
+including but not limited to software source code, documentation source,
+and configuration files.
 
-Except as expressly stated above, no rights or licenses
-from any copyright holder or contributor is granted under
-this license, whether expressly, by implication, estoppel
-or otherwise.
+**"Object" form** shall mean any form resulting from mechanical
+transformation or translation of a Source form, including but not
+limited to compiled object code, generated documentation, and
+conversions to other media types.
 
+**"Work"** shall mean the work of authorship, whether in Source or
+Object form, made available under the License, as indicated by a
+copyright notice that is included in or attached to the work
+(an example is provided in the Appendix below).
 
-DISCLAIMER
+**"Derivative Works"** shall mean any work, whether in Source or Object
+form, that is based on (or derived from) the Work and for which the
+editorial revisions, annotations, elaborations, or other modifications
+represent, as a whole, an original work of authorship. For the purposes
+of this License, Derivative Works shall not include works that remain
+separable from, or merely link (or bind by name) to the interfaces of,
+the Work and Derivative Works thereof.
 
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
-CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
-WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
-INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
-DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
-PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
-ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
-LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
-IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+**"Contribution"** shall mean any work of authorship, including the
+original version of the Work and any modifications or additions to that
+Work or Derivative Works thereof, that is intentionally submitted to
+the Licensor for inclusion in the Work by the copyright owner or by an
+individual or Legal Entity authorized to submit on behalf of the
+copyright owner.
 
-YOU ACKNOWLEDGE THAT THIS SOFTWARE IS NOT DESIGNED,
-LICENSED OR INTENDED FOR USE IN THE DESIGN, CONSTRUCTION,
-OPERATION OR MAINTENANCE OF ANY MILITARY FACILITY OR
-RELIGIOUS INSTITUTION.
+**"Contributor"** shall mean Licensor and any individual or Legal Entity
+on behalf of whom a Contribution has been received by Licensor and
+subsequently incorporated within the Work.
+
+### 2. Grant of Copyright License.
+
+Subject to the terms and conditions of this License, each Contributor
+hereby grants to You a perpetual, worldwide, non-exclusive, no-charge,
+royalty-free, irrevocable copyright license to reproduce, prepare
+Derivative Works of, publicly display, publicly perform, sublicense,
+and distribute the Work and such Derivative Works in Source or Object
+form.
+
+### 3. Grant of Patent License.
+
+Subject to the terms and conditions of this License, each Contributor
+hereby grants to You a perpetual, worldwide, non-exclusive, no-charge,
+royalty-free, irrevocable (except as stated in this section) patent
+license to make, have made, use, offer to sell, sell, import, and
+otherwise transfer the Work, where such license applies only to those
+patent claims licensable by such Contributor that are necessarily
+infringed by their Contribution(s) alone or by combination of their
+Contribution(s) with the Work to which such Contribution(s) was
+submitted. If You institute patent litigation against any entity
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+the Work or a Contribution incorporated within the Work constitutes
+direct or contributory patent infringement, then any patent licenses
+granted to You under this License for that Work shall terminate as of
+the date such litigation is filed.
+
+### 4. Redistribution.
+
+You may reproduce and distribute copies of the Work or Derivative Works
+thereof in any medium, with or without modifications, and in Source or
+Object form, provided that You meet the following conditions:
+
+1. You must give any other recipients of the Work or Derivative Works a
+   copy of this License; and
+
+2. You must cause any modified files to carry prominent notices stating
+   that You changed the files; and
+
+3. You must retain, in the Source form of any Derivative Works that You
+   distribute, all copyright, patent, trademark, and attribution notices
+   from the Source form of the Work, excluding those notices that do not
+   pertain to any part of the Derivative Works; and
+
+4. If the Work includes a "NOTICE" text file as part of its distribution,
+   then any Derivative Works that You distribute must include a readable
+   copy of the attribution notices contained within such NOTICE file,
+   excluding those notices that do not pertain to any part of the
+   Derivative Works, in at least one of the following places: within a
+   NOTICE text file distributed as part of the Derivative Works; within
+   the Source form or documentation, if provided along with the Derivative
+   Works; or, within a display generated by the Derivative Works, if and
+   wherever such third-party notices normally appear. The contents of the
+   NOTICE file are for informational purposes only and do not modify the
+   License. You may add Your own attribution notices within Derivative
+   Works that You distribute, alongside or as an addendum to the NOTICE
+   text from the Work, provided that such additional attribution notices
+   cannot be construed as modifying the License.
+
+You may add Your own copyright statement to Your modifications and may
+provide additional or different license terms and conditions for use,
+reproduction, or distribution of Your modifications, or for any such
+Derivative Works as a whole, provided Your use, reproduction, and
+distribution of the Work otherwise complies with the conditions stated
+in this License.
+
+### 5. Submission of Contributions.
+
+Unless You explicitly state otherwise, any Contribution intentionally
+submitted for inclusion in the Work by You to the Licensor shall be
+under the terms and conditions of this License, without any additional
+terms or conditions. Notwithstanding the above, nothing herein shall
+supersede or modify the terms of any separate license agreement you
+may have executed with Licensor regarding such Contributions.
+
+### 6. Trademarks.
+
+This License does not grant permission to use the trade names,
+trademarks, service marks, or product names of the Licensor, except as
+required for describing the origin of the Work and reproducing the
+content of the NOTICE file.
+
+### 7. Disclaimer of Warranty.
+
+Unless required by applicable law or agreed to in writing, Licensor
+provides the Work (and each Contributor provides its Contributions) on
+an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+express or implied, including, without limitation, any warranties or
+conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR
+A PARTICULAR PURPOSE. You are solely responsible for determining the
+appropriateness of using or redistributing the Work and assume any
+risks associated with Your exercise of permissions under this License.
+
+### 8. Limitation of Liability.
+
+In no event and under no legal theory, whether in tort (including
+negligence), contract, or otherwise, unless required by applicable law
+(such as deliberate and grossly negligent acts) or agreed to in writing,
+shall any Contributor be liable to You for damages, including any direct,
+indirect, special, incidental, or consequential damages of any character
+arising as a result of this License or out of the use or inability to use
+the Work (including but not limited to damages for loss of goodwill, work
+stoppage, computer failure or malfunction, or any and all other commercial
+damages or losses), even if such Contributor has been advised of the
+possibility of such damages.
+
+### 9. Accepting Warranty or Additional Liability.
+
+While redistributing the Work or Derivative Works thereof, You may choose
+to offer, and charge a fee for, acceptance of support, warranty, indemnity,
+or other liability obligations and/or rights consistent with this License.
+However, in accepting such obligations, You may act only on Your own behalf
+and on Your sole responsibility, not on behalf of any other Contributor,
+and only if You agree to indemnify, defend, and hold each Contributor
+harmless for any liability incurred by, or claims asserted against, such
+Contributor by reason of your accepting any such warranty or additional
+liability.
diff --git a/README.md b/README.md
index 0f3cb01..f14cf6d 100644
--- a/README.md
+++ b/README.md
@@ -49,3 +49,19 @@ Library avoids panics where possible and returns Result<T, &str> for error handl
 
 ## References
 [SPP]: https://ccsds.org/wp-content/uploads/gravity_forms/5-448e85c647331d9cbaf66c096458bdd5/2025/01//133x0b2e2.pdf "CCSDS Space Packet Protocol PDF"
+
+
+---
+
+## Copyright & License
+
+Copyright 2025 CyberMages LLC
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this library except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS
diff --git a/docs/ccsds_spp.pdf b/docs/ccsds_spp.pdf
new file mode 100644
index 0000000..ebb0c1a
Binary files /dev/null and b/docs/ccsds_spp.pdf differ