[ja_JP] What’s new in Hyperledger Fabric v2.x

[shimos]

Original HTML: https://hyperledger-fabric.readthedocs.io/en/release-2.5/whatsnew.html
Original Source: https://github.com/hyperledger/fabric/blob/e1e8e2e52aa4fc543360d245fe6554a0eaf81183/docs/source/whatsnew.rst

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@@ -1,21 +1,142 @@
 What's new in Hyperledger Fabric v2.x
 =====================================
 
+What's New in Hyperledger Fabric v2.5
+-------------------------------------
+
+Purge history of private data
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+While it has always been possible to delete private data from current state, this new feature enables purging the history of private data from a peer while preserving a hash of the private data as immutable evidence on the blockchain.
+
+* Useful for purging private data on demand for privacy reasons or to adhere to government regulations.
+* Deletes private data from state and from peer’s private data history so that it can no longer be queried from block events or from other peers.
+* Available as a new chaincode API `PurgePrivateData()`.
+* Requires setting application capability to `V2_5` in channel configuration
+
+For more details, see the :doc:`private-data/private-data` topic.
+
+Multi-architecture binaries and docker images are now available
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The release binaries and docker images have been updated as follows:
+
+* Support for amd64 and arm64.
+* Release binaries are statically linked for maximum portability.
+* Docker images utilize dynamically linked binaries and are now based on Ubuntu (rather than Alpine) to make them more consistent with typical production runtime environments (production runtime environments are typically based on glibc and often require dynamic linking of HSM modules).
+
+.. note::
+
+   Fabric v2.5.x is the current long-term support (LTS) release. A simple in-place upgrade from the prior LTS (Fabric v2.2.x) release is possible.
+
+
+What's New in Hyperledger Fabric v2.4
+-------------------------------------
+
+Fabric Gateway
+^^^^^^^^^^^^^^
+
+Fabric Gateway is a new service running on peer nodes that manages transaction submission and processing for client applications, with the following benefits:
+
+* Simplifies client applications and SDKs - Your client application can simply delegate transaction submission to a trusted peer. There is no need for your application to open connections to peer nodes and ordering service nodes from other organizations.
+* Fabric Gateway manages the collection of transaction endorsements from other organizations and submission to the ordering service on behalf of client applications.
+* Fabric Gateway has intelligence to determine what endorsements are required for a given transaction, even if your solution utilizes a combination of chaincode-level endorsement policies, private data collection endorsement policies, and state-based endorsement policies.
+
+New lightweight Gateway SDKs (v1.0.0) are available for Node, Java, and Go. The SDKs support flexible application patterns:
+
+* You can utilize the high-level programming model similar to prior SDK versions, allowing your application to simply call a single SubmitTransaction() function.
+* More advanced applications can leverage the gateway's individual Endorse, Submit, and CommitStatus services for transaction submission, and the Evaluate service for queries.
+* You can delegate transaction endorsement entirely to the gateway, or if needed, specify the endorsing organizations and the gateway will utilize a peer from each organization.
+
+For more information, see the :doc:`gateway` topic.
+
+Peer node unjoin
+^^^^^^^^^^^^^^^^
+
+You can now unjoin a peer from a channel when the channel is no longer needed. All channel resources will be removed from the peer and the peer will no longer process blocks from the channel.
+
+For more details, see the `peer node unjoin` :doc:`command reference topic<commands/peernode>`.
+
+Calculate package ID of a packaged chaincode
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+You can calculate the package ID from a packaged chaincode without installing the chaincode on peers using the new `peer lifecycle chaincode calculatepackageid` command.
+This command will be useful, for example, in the following scenarios:
+
+* When multiple chaincode packages with the same label name are installed, it is possible to identify which ID corresponds to which package later.
+* To check whether a particular chaincode package is installed or not without installing that package.
+
+For more information, see the `peer lifecycle chaincode calculatepackageid` :doc:`command reference topic<commands/peerlifecycle>`.
+
+
+What's New in Hyperledger Fabric v2.3
+-------------------------------------
+
+Hyperledger Fabric v2.3 introduces two new features for improved orderer and peer operations.
+
+Orderer channel management without a system channel
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+To simplify the channel creation process and enhance the privacy and scalability of channels,
+it is now possible to create application channels without first creating a “system channel” managed by the ordering service.
+This process allows ordering nodes to join (or leave) any number of channels as needed, similar to how peers can participate in multiple channels.
+
+Benefits of the new process:
+
+* **Increased privacy:** Because all ordering nodes used to be joined to the system channel,
+  every ordering node in a network knew about the existence of every channel on that ordering service.
+  Now, an ordering node only knows about the channels it is joined to.
+* **Scalability:** When there is a large number of ordering nodes and channels defined on the system channel,
+  it can take a long time for ordering nodes to reach consensus on the membership of all the channels.
+  Now, an ordering service can scale horizontally in a decentralized fashion by independently joining ordering nodes to specific channels.
+* **Operational benefits**
+   * Simple process to join an ordering node to a channel.
+   * Ability to list the channels that the ordering node is a consenter on.
+   * Simple process to remove a channel from an ordering node, which automatically cleans up the blocks associated with that channel.
+   * Peer organizations do not need to coordinate with an admin of the system channel to create or update its MSP.
+
+For more information, see the :doc:`create_channel/create_channel_participation` topic.
+
+Ledger snapshot
+^^^^^^^^^^^^^^^
+
+It is now possible to take a snapshot of a peer's channel information, including its state database,
+and join new peers (in the same organization or different organizations) to the channel based on the snapshot.
+
+Using ledger snapshots has the following advantages:
+
+* **Peers don't need to process all blocks since genesis block:** Peers can join a channel without processing all
+  previous blocks since the genesis block, greatly reducing the time it takes to join a peer to an existing channel.
+* **Peers can join channels using latest channel configuration:** Because snapshots include the latest channel configuration,
+  peers can now join a channel using the latest channel configuration.
+  This is especially important if critical channel configuration such as orderer endpoints or TLS CA certificates have been updated since the genesis block.
+* **Reduced storage costs:** Peers that join by snapshot do not incur the storage cost of maintaining all blocks since the genesis block.
+* **State checkpoints:** Peer administrators can snapshot current channel state and compare with other peers,
+  in the same organization or different organizations, to verify the consistency and integrity of the ledger on each peer.
+  Agreed upon snapshots can be used as a checkpoint and basis for newly joining peers.
+
+For more information, see the :doc:`peer_ledger_snapshot` topic.
+
+.. note::
+
+   While Fabric v2.3.0 introduces new features, Fabric v2.2.x remains the current long-term support release until the next LTS release is announced.
+
+What's New in Hyperledger Fabric v2.0, v2.1, v2.2
+-------------------------------------------------
+
 The first Hyperledger Fabric major release since v1.0, Fabric v2.0
 delivers important new features and changes for users and operators alike,
 including support for new application and privacy patterns, enhanced
 governance around smart contracts, and new options for operating nodes.
 
-Each v2.x minor release builds on the v2.0 release with minor features,
-improvements, and bug fixes.
-
-v2.2 is the first long-term support (LTS) release of Fabric v2.x.
+v2.1 and v2.2 build on the v2.0 release with minor features,
+improvements, and bug fixes, with v2.2 being the first long-term support (LTS) release of Fabric v2.x.
 Fixes will be provided on the v2.2.x release stream until after the next LTS release is announced.
 
 Let's take a look at some of the highlights of the Fabric v2.0 release...
 
 Decentralized governance for smart contracts
---------------------------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Fabric v2.0 introduces decentralized governance for smart contracts, with a new
 process for installing a chaincode on your peers and starting it on a channel.
@@ -24,7 +145,7 @@ agreement on the parameters of a chaincode, such as the chaincode endorsement
 policy, before it can be used to interact with the ledger. The new model
 offers several improvements over the previous lifecycle:
 
-* **Multiple organizations must agree to the parameters of a chaincode**
+* **Multiple organizations must agree to the parameters of a chaincode:**
   In the release 1.x versions of Fabric, one organization had the ability to
   set parameters of a chaincode (for instance the endorsement policy) for all
   other channel members, who only had the power to refuse to install the chaincode
@@ -35,13 +156,13 @@ offers several improvements over the previous lifecycle:
   agree on an endorsement policy and other details before the chaincode
   becomes active on a channel.
 
-* **More deliberate chaincode upgrade process** In the previous chaincode
+* **More deliberate chaincode upgrade process:** In the previous chaincode
   lifecycle, the upgrade transaction could be issued by a single organization,
   creating a risk for a channel member that had not yet installed the new
   chaincode. The new model allows for a chaincode to be upgraded only after
   a sufficient number of organizations have approved the upgrade.
 
-* **Simpler endorsement policy and private data collection updates**
+* **Simpler endorsement policy and private data collection updates:**
   Fabric lifecycle allows you to change an endorsement policy or private
   data collection configuration without having to repackage or reinstall
   the chaincode. Users can also take advantage of a new default endorsement
@@ -49,18 +170,18 @@ offers several improvements over the previous lifecycle:
   channel. This policy is updated automatically when organizations are
   added or removed from the channel.
 
-* **Inspectable chaincode packages** The Fabric lifecycle packages chaincode
+* **Inspectable chaincode packages:** The Fabric lifecycle packages chaincode
   in easily readable tar files. This makes it easier to inspect the chaincode
   package and coordinate installation across multiple organizations.
 
-* **Start multiple chaincodes on a channel using one package** The previous
+* **Start multiple chaincodes on a channel using one package:** The previous
   lifecycle defined each chaincode on the channel using a name and version
   that was specified when the chaincode package was installed. You can now
   use a single chaincode package and deploy it multiple times with different
   names on the same channel or on different channels. For example, if you’d
   like to track different types of assets in their own ‘copy’ of the chaincode.
 
-* **Chaincode packages do not need to be identical across channel members**
+* **Chaincode packages do not need to be identical across channel members:**
   Organizations can extend a chaincode for their own use case, for example
   to perform different validations in the interest of their organization.
   As long as the required number of organizations endorse chaincode transactions
@@ -68,9 +189,6 @@ offers several improvements over the previous lifecycle:
   ledger.  This also allows organizations to individually roll out minor fixes
   on their own schedules without requiring the entire network to proceed in lock-step.
 
-Using the new chaincode lifecycle
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
 For existing Fabric deployments, you can continue to use the prior chaincode
 lifecycle with Fabric v2.x. The new chaincode lifecycle will become effective
 only when the channel application capability is updated to v2.0.
@@ -78,18 +196,18 @@ See the :doc:`chaincode_lifecycle` concept topic for an overview of the new
 chaincode lifecycle.
 
 New chaincode application patterns for collaboration and consensus
-------------------------------------------------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 The same decentralized methods of coming to agreement that underpin the
 new chaincode lifecycle management can also be used in your own chaincode
 applications to ensure organizations consent to data transactions before
 they are committed to the ledger.
 
-* **Automated checks** As mentioned above, organizations can add automated
+* **Automated checks:** As mentioned above, organizations can add automated
   checks to chaincode functions to validate additional information before
   endorsing a transaction proposal.
 
-* **Decentralized agreement** Human decisions can be modeled into a chaincode process
+* **Decentralized agreement:** Human decisions can be modeled into a chaincode process
   that spans multiple transactions. The chaincode may require actors from
   various organizations to indicate their terms and conditions of agreement
   in a ledger transaction. Then, a final chaincode proposal can
@@ -99,7 +217,7 @@ they are committed to the ledger.
   see the asset transfer scenario in the :doc:`private-data/private-data` documentation.
 
 Private data enhancements
--------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Fabric v2.0 also enables new patterns for working with and sharing private data,
 without the requirement of creating private data collections for all
@@ -111,14 +229,14 @@ with a regulator or auditor.
 
 Several enhancements in Fabric v2.x make these new private data patterns possible:
 
-* **Sharing and verifying private data** When private data is shared with a
+* **Sharing and verifying private data:** When private data is shared with a
   channel member who is not a member of a collection, or shared with another
   private data collection that contains one or more channel members (by writing
   a key to that collection), the receiving parties can utilize the
   GetPrivateDataHash() chaincode API to verify that the private data matches the
   on-chain hashes that were created from private data in previous transactions.
 
-* **Collection-level endorsement policies** Private data collections can now
+* **Collection-level endorsement policies:** Private data collections can now
   optionally be defined with an endorsement policy that overrides the
   chaincode-level endorsement policy for keys within the collection. This
   feature can be used to restrict which organizations can write data to a
@@ -128,7 +246,7 @@ Several enhancements in Fabric v2.x make these new private data patterns possibl
   but for any given transaction, you may need two transacting organizations
   to individually endorse their agreement in their own private data collections.
 
-* **Implicit per-organization collections** If you’d like to utilize
+* **Implicit per-organization collections:** If you’d like to utilize
   per-organization private data patterns, you don’t even need to define the
   collections when deploying chaincode in Fabric v2.x.  Implicit
   organization-specific collections can be used without any upfront definition.
@@ -138,26 +256,26 @@ documentation). For details about private data collection configuration and
 implicit collections, see the :doc:`private-data-arch` (reference documentation).
 
 External chaincode launcher
----------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 The external chaincode launcher feature empowers operators to build and launch
 chaincode with the technology of their choice. Use of external builders and launchers
 is not required as the default behavior builds and runs chaincode in the same manner
 as prior releases using the Docker API.
 
-* **Eliminate Docker daemon dependency** Prior releases of Fabric required
+* **Eliminate Docker daemon dependency:** Prior releases of Fabric required
   peers to have access to a Docker daemon in order to build and launch
   chaincode - something that may not be desirable in production environments
   due to the privileges required by the peer process.
 
-* **Alternatives to containers** Chaincode is no longer required to be run
+* **Alternatives to containers:** Chaincode is no longer required to be run
   in Docker containers, and may be executed in the operator’s choice of
   environment (including containers).
 
-* **External builder executables** An operator can provide a set of external
+* **External builder executables:** An operator can provide a set of external
   builder executables to override how the peer builds and launches chaincode.
 
-* **Chaincode as an external service** Traditionally, chaincodes are launched
+* **Chaincode as an external service:** Traditionally, chaincodes are launched
   by the peer, and then connect back to the peer. It is now possible to run chaincode as
   an external service, for example in a Kubernetes pod, which a peer can
   connect to and utilize for chaincode execution. See :doc:`cc_service` for more
@@ -166,7 +284,7 @@ as prior releases using the Docker API.
 See :doc:`cc_launcher` to learn more about the external chaincode launcher feature.
 
 State database cache for improved performance on CouchDB
---------------------------------------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 * When using external CouchDB state database, read delays during endorsement
   and validation phases have historically been a performance bottleneck.
@@ -176,7 +294,7 @@ State database cache for improved performance on CouchDB
   core.yaml property ``cacheSize``.
 
 Alpine-based docker images
---------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Starting with v2.0, Hyperledger Fabric Docker images will use Alpine Linux,
 a security-oriented, lightweight Linux distribution. This means that Docker
@@ -186,7 +304,7 @@ from the ground up with security in mind, and the minimalist nature of the Alpin
 distribution greatly reduces the risk of security vulnerabilities.
 
 Sample test network
--------------------
+^^^^^^^^^^^^^^^^^^^
 
 The fabric-samples repository now includes a new Fabric test network. The test
 network is built to be a modular and user friendly sample Fabric network that
@@ -197,11 +315,12 @@ in addition to cryptogen.
 For more information about this network, check out :doc:`test_network`.
 
 Upgrading to Fabric v2.x
-------------------------
+^^^^^^^^^^^^^^^^^^^^^^^^
 
 A major new release brings some additional upgrade considerations. Rest assured
 though, that rolling upgrades from v1.4.x to v2.0 are supported, so that network
-components can be upgraded one at a time with no downtime.
+components can be upgraded one at a time with no downtime. You can also upgrade
+directly from the v1.4.x LTS release to the v2.2.x LTS release or v2.5.x LTS release.
 
 The upgrade docs have been significantly expanded and reworked, and now have a
 standalone home in the documentation: :doc:`upgrade`. Here you'll find documentation on
@@ -212,17 +331,13 @@ Release notes
 =============
 
 The release notes provide more details for users moving to the new release.
-Specifically, take a look at the changes and deprecations
-announced in each of the v2.x releases.
-
-* `Fabric v2.0.0 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.0.0>`_.
-* `Fabric v2.0.1 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.0.1>`_.
-* `Fabric v2.1.0 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.1.0>`_.
-* `Fabric v2.1.1 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.1.1>`_.
-* `Fabric v2.2.0 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.2.0>`_.
-* `Fabric v2.2.1 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.2.1>`_.
-* `Fabric v2.2.2 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.2.2>`_.
-* `Fabric v2.2.3 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.2.3>`_.
+Specifically, take a look at the changes and deprecations.
+
+* `Fabric v2.5.0 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.5.0>`_.
+* `Fabric v2.5.1 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.5.1>`_.
+* `Fabric v2.5.2 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.5.2>`_.
+* `Fabric v2.5.3 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.5.3>`_.
+* `Fabric v2.5.4 release notes <https://github.com/hyperledger/fabric/releases/tag/v2.5.4>`_.
 
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    https://creativecommons.org/licenses/by/4.0/