dco in contributing.md

Signed-off-by: Kavitha Conjeevaram Mohan <[email protected]>

CONTRIBUTING.md

@@ -19,42 +19,50 @@ reported the issue. Please try to include as much information as you can. Detail
 * Any modifications you've made relevant to the bug
 * Anything unusual about your environment or deployment
 
-## Sign your work
-The sign-off is a simple line at the end of each commit, which certifies that you wrote it or otherwise have the right to pass it on as an open-source patch. if you can certify the below
+## Developer Certificate of Origin
+
+OpenSearch is an open source product released under the Apache 2.0 license (see either [the Apache site](https://www.apache.org/licenses/LICENSE-2.0) or the [LICENSE.txt file](./LICENSE.txt)). The Apache 2.0 license allows you to freely use, modify, distribute, and sell your own products that include Apache 2.0 licensed software.
+
+We respect intellectual property rights of others and we want to make sure all incoming contributions are correctly attributed and licensed. A Developer Certificate of Origin (DCO) is a lightweight mechanism to do that.
+
+The DCO is a declaration attached to every contribution made by every developer. In the commit message of the contribution, the developer simply adds a `Signed-off-by` statement and thereby agrees to the DCO, which you can find below or at [DeveloperCertificate.org](http://developercertificate.org/).
+
 ```
+Developer's Certificate of Origin 1.1
+
 By making a contribution to this project, I certify that:
+
 (a) The contribution was created in whole or in part by me and I
-have the right to submit it under the open source license
-indicated in the file; or
-(b) The contribution is based upon previous work that, to the best
-of my knowledge, is covered under an appropriate open source
-license and I have the right under that license to submit that
-work with modifications, whether created in whole or in part
-by me, under the same open source license (unless I am
-permitted to submit under a different license), as indicated
-in the file; or
+    have the right to submit it under the open source license
+    indicated in the file; or
+
+(b) The contribution is based upon previous work that, to the
+    best of my knowledge, is covered under an appropriate open
+    source license and I have the right under that license to
+    submit that work with modifications, whether created in whole
+    or in part by me, under the same open source license (unless
+    I am permitted to submit under a different license), as
+    Indicated in the file; or
+
 (c) The contribution was provided directly to me by some other
-person who certified (a), (b) or (c) and I have not modified
-it.
+    person who certified (a), (b) or (c) and I have not modified
+    it.
+
 (d) I understand and agree that this project and the contribution
-are public and that a record of the contribution (including all
-personal information I submit with it, including my sign-off) is
-maintained indefinitely and may be redistributed consistent with
-this project or the open source license(s) involved.
-```
-then you just add a line to every git commit message:
-```
-Signed-off-by: Bob Sanders <[email protected]>
-```
-You can sign off your work easily by adding the configuration in github
-```
-git config user.name "Bob Sanders"
-git config user.email "[email protected]"
-```
-Then, you could sign off commits automatically by adding `-s` or `-=signoff` parameter to your usual git commits commands. e.g.
+    are public and that a record of the contribution (including
+    all personal information I submit with it, including my
+    sign-off) is maintained indefinitely and may be redistributed
+    consistent with this project or the open source license(s)
+    involved.
+ ```
+We require that every contribution to OpenSearch is signed with a Developer Certificate of Origin. Additionally, please use your real name. We do not accept anonymous contributors nor those utilizing pseudonyms.
+
+Each commit must include a DCO which looks like this
+
 ```
-git commit -s -m "my first commit"
+Signed-off-by: Jane Smith <[email protected]>
 ```
+You may type this line on your own when writing your commit messages. However, if your user.name and user.email are set in your git configs, you can use `-s` or `--signoff` to add the `Signed-off-by` line to the end of the commit message.
 
 ## Contributing via Pull Requests
 Contributions via pull requests are much appreciated. Before sending us a pull request, please ensure that: