Merge pull request 0xPolygon#42 from 0xPolygon/km/cdk_finalizing

CDK updates after Gabriel review

Author: EmpieichO

docs/cdk/concepts/dac.md

@@ -5,14 +5,7 @@ If data is available on-chain, then each node has to store every piece of data r
 !!! info "Recommended resource"
     See Ethereum.org's discussion on [data availability](https://ethereum.org/en/developers/docs/data-availability/).
 
-## What is a validium?
-
-Validiums are blockchain solutions that do not store transaction data. 
-
-!!! info "Recommended resource"
-    See Ethereum.org's glossary [definition of validiums](https://ethereum.org/en/developers/docs/scaling/validium/).
-
-## What is a DAC?
+## Data availability committees
 
 Polygon's CDK validium has an optional data availability committee (DAC).
 

docs/cdk/concepts/rollup.md

@@ -0,0 +1,6 @@
+Rollups are blockchain layer 2 scaling solutions that speed up the network by *rolling up* multiple transactions into batches which are eventually committed to the layer 1. 
+
+CDK provides zkEVM rollup solutions.
+
+!!! info "Recommended resource"
+    See Ethereum.org's detailed [description of zero-knowledge rollups](https://ethereum.org/en/developers/docs/scaling/zk-rollups/).

docs/cdk/concepts/validium.md

@@ -0,0 +1,4 @@
+Validiums are blockchain scaling solutions that do not store transaction data. 
+
+!!! info "Recommended resource"
+    See Ethereum.org's detailed [description of validiums](https://ethereum.org/en/developers/docs/scaling/validium/).

docs/cdk/get-started/deploy-validium.md

@@ -20,4 +20,4 @@ Follow the instructions in the [CDK validium node repository's README](https://g
 
 Finally, once the CDK validium node is operational, set up and run the data availability node. 
 
-Check for instructions here: [<ins>CDK DA Node GitHub repository's README</ins>](https://github.com/0xPolygon/cdk-data-availability).
+Check for instructions here: [<ins>CDK DA Node GitHub running instructions</ins>](https://github.com/0xPolygon/cdk-data-availability/blob/main/docs/running.md).

docs/cdk/get-started/overview.md

@@ -1,13 +1,20 @@
-Polygon's Chain Development Kit (CDK) is a modular, open source software tool for blockchain developers which supports installation and configuration of a variety of chain architectures.
+Polygon’s Chain Development Kit (CDK) is a modular, open source software toolkit for blockchain developers which supports installation and configuration of a variety of chain architectures.  
 
-!!! important
-    At the time of writing, CDK offers rollup and validium configurations.
+This section documents the two most popular deployments currently supported by CDK:
+
+- Validium
+- Rollup
+
+Users select a chain architecture specific to their needs from a set of supported, open source options. Alternatively, users can select custom components for specific requirements. 
 
-CDK users choose a chain architecture specific to their needs and use cases.
+The diagram below shows the two supported configuration options for data availability (DA), rollup or validium. Rollups post transaction data from the CDK directly onto Ethereum whereas validiums only post the transaction hash.
 
-<center>
-![CDK flavors](../../img/cdk/cdk-modes.png) 
-</center>
+![CDK architecture choices](../../img/cdk/cdk-architecture.png)
+
+Check out the [data availability docs](../concepts/dac.md) for more information.
+
+!!! important
+    The documentation describes standard deployments. You can edit the configuration files to implement your own custom set ups.
 
 !!! info
     For the latest updates, follow our official GitHub repositories.

docs/cdk/specification/validium-vs-rollup.md

@@ -7,15 +7,14 @@ Polygon CDK running in validium mode inherits the core functionalities of a zkEV
 |        | Rollup                                                    | Validium                                                                           |
 | ------------------------ | ----------------------------------------------------------- | ---------------------------------------------------------------------------------- |
 | **Node type**            | [zkEVM node](https://github.com/0xPolygonHermez/zkevm-node) | [Validium node](https://github.com/0xPolygon/cdk-validium-node): zkEVM node with validium extensions                  |
-| **Data availability**    | On-chain                                                    | Off-chain via DACs + [DA node](https://github.com/0xPolygon/cdk-data-availability) |
+| **Data availability**    | On-chain via L1                                            | Off-chain via a local option, or a [DAC](../concepts/dac.md) + [DA node](https://github.com/0xPolygon/cdk-data-availability) |
 | **Components**           | zkEVM components\*                                        | zkEVM components\* + PostgreSQL database + on-chain committees                   |
 | **Contracts** | [zkEVM smart contracts](https://github.com/0xPolygonHermez/zkevm-contracts)  <ul><li>`PolygonZkEVM` (main rollup contract)</li> <li> `PolygonZkEVMBridge`</li> <li>`PolygonZkEVMGlobalExitRoot`</li></ul>  | [Validium-specific DAC contract](https://github.com/0xPolygon/cdk-validium-contracts) <ul><li>`CDKDataCommittee.sol`</li><li> `CDKValidium.sol` </li></ul> |
 | **Infrastructure** | Standard infrastructure                                     | Dedicated infrastructure for data availability layer and DACs                      |
-| **Tx flow** | All transaction data is published on L1 | Validium only publishes the hash of the transaction data. This `Accumulated Input Hash` must be approved by a majority of DAC members. <br/><br/>The sequencer sends both the hash and the transaction data to the DAC for verification. Once approved, the hash plus signatures, is sent to the Consensus L1 contract of the validium protocol. <br/><br/> After verification, the hash and the zk-proof are added to the L1 state.
-| **Security** | High security due to on-chain data availability and zero-knowledge proofs. |Off-chain data availability can affect security if DAC members collude to withhold state data. However, security still good due to zero-knowledge proofs. |
+| **Tx flow** | All transaction data is published on L1 | Validium only publishes the hash of the transaction data to L1. The sequencer sends both the hash and the transaction data to the DAC for verification. Once approved, the hash+signatures are sent to the Consensus L1 contract of the validium protocol. 
+| **Security** | High security due to on-chain data availability and zero-knowledge proofs. |Off-chain data availability can affect security if the sequencer goes offline or if DAC members collude to withhold state data. |
 | **Gas fees** | High, because all transaction data is stored on Ethereum. | Low, because only the hash of the transaction data is stored on Ethereum. |
 | **Proof generation** | Uses Prover to generate proofs of batched transactions for validation. | Uses Prover to generate proofs of batched transactions for validation. |
-| **Transaction validation** | Done with smart contracts on Ethereum. | Involves an additional layer where DAC members sign the hash of the transaction data. |
 | **Final settlement** | Transaction batches and their corresponding proofs are added to the Ethereum state. | The hash of transaction data and its proof are added to the Ethereum state, referred to as the consolidated state. |
 
 <sub><sup>*</sup>JSON RPC, Pool DB, Sequencer, Etherman, Synchronizer, State DB, Aggregator, Prover</sub>

docs/img/cdk/cdk-architecture.png

@@ -1,7 +1,7 @@
 site_name: Polygon knowledge layer
 site_author: Polygon Labs
 copyright: Copyright © 2023 Polygon Labs
-repo_name: Polygon Knowledge Layer
+repo_name: Polygon knowledge layer
 repo_url: https://github.com/0xPolygon/polygon-docs
 edit_uri: edit/main/docs/
 #remote_branch: gh-pages
@@ -67,6 +67,8 @@ nav:
       - Specification:
         - Validium vs rollup: cdk/specification/validium-vs-rollup.md
       - Concepts:
+        - Rollup: cdk/concepts/rollup.md
+        - Validium: cdk/concepts/validium.md
         - Data availability: cdk/concepts/dac.md
      # - API:
       - Troubleshooting: