Merge "FAB-3099 migrate unmerged capabilities.md"

docs/source/capabilities.rst

@@ -1,7 +1,72 @@
-Capabilities
-------------
+Fabric Capabilities
+===================
 
-...coming soon
+Hyperledger Fabric is a unique implementation of distributed ledger technology
+(DLT) that delivers enterprise-ready network security, scalability,
+confidentiality and performance, in a modular blockchain architecture. The
+fabric delivers the following blockchain network capabilities:
 
-Identity Management, Privacy, Confidentiality, Throughput, Chaincode,
-Modularity
+Identity management
+-------------------
+
+To enable permissioned networks, Hyperledger Fabric provides a membership
+identity service that manages user IDs and authenticates all participants on
+the network. Access control lists can be used to provide additional layers of
+permission through authorization of specific network operations. For example, a
+specific user ID could be permitted to invoke a chaincode application, but
+blocked from deploying new chaincode. One truism about Hyperledger Fabric
+networks is that members know each other (identity), but they do not know what
+each other are doing (privacy and confidentiality).
+
+Privacy and confidentiality
+---------------------------
+
+Hyperledger Fabric enables competing business interests, and any groups that
+require private, confidential transactions, to coexist on the same permissioned
+network. Private **channels** are restricted messaging paths that can be used
+to provide transaction privacy and confidentiality for specific subsets of
+network members. All data, including transaction, member and channel
+information, on a channel are invisible and inaccessible to any network members
+not explicitly granted access to that channel.
+
+Efficient processing
+--------------------
+
+Hyperledger Fabric assigns network roles by node type. To provide concurrency
+and parallelism to the network, transaction execution is separated from
+transaction ordering and commitment. Executing transactions prior to
+ordering them enables each peer node to process multiple transactions
+simultaneously. This concurrent execution increases processing efficiency on
+each peer and accelerates delivery of transactions to the ordering service.
+
+In addition to enabling parallel processing, the division of labor unburdens
+ordering nodes from the demands of transaction execution and ledger
+maintenance, while peer nodes are freed from ordering (consensus) workloads.
+This bifurcation of roles also limits the processing required for authorization
+and authentication; all peer nodes do not have to trust all ordering nodes, and
+vice versa, so processes on one can run independently of verification by the
+other.
+
+Chaincode functionality
+-----------------------
+
+Chaincode applications encode logic that is
+invoked by specific types of transactions on the channel. Chaincode that
+defines parameters for a change of asset ownership, for example, ensures that
+all transactions that transfer ownership are subject to the same rules and
+requirements. **System chaincode** is distinguished as chaincode that defines
+operating parameters for the entire channel. Lifecycle and configuration system
+chaincode defines the rules for the channel; endorsement and validation system
+chaincode defines the requirements for endorsing and validating transactions.
+
+Modular design
+--------------
+
+Hyperledger Fabric implements a modular architecture to
+provide functional choice to network designers. Specific algorithms for
+identity, ordering (consensus) and encryption, for example, can be plugged in
+to any fabric network. The result is a universal blockchain architecture that
+any industry or public domain can adopt, with the assurance that its networks
+will be interoperable across market, regulatory and geographic boundaries. By
+contrast, current alternatives to Hyperledger Fabric are largely partisan,
+constrained and industry-specific.