github.com/leonlxy/hyperledger@v1.0.0-alpha.0.20170427033203-34922035d248/docs/source/FAQ/identity_management_FAQ.rst (about) 1 Identity Management (Membership Service) 2 ---------------------------------------- 3 4 * What is unique about the fabric's Membership Service module? 5 6 One of the things that makes the Membership Service module stand out from 7 the pack is our implementation of the latest advances in cryptography. 8 9 In addition to ensuring private, auditable transactions, our Membership 10 Service module introduces the concept of enrollment and transaction 11 certificates. This innovation ensures that only verified owners can 12 create asset tokens, allowing an infinite number of transaction 13 certificates to be issued through parent enrollment certificates while 14 guaranteeing the private keys of asset tokens can be regenerated if 15 lost. 16 17 Issuers also have the ability revoke transaction certificates or 18 designate them to expire within a certain timeframe, allowing greater 19 control over the asset tokens they have issued. 20 21 Like most other modules on Fabric, you can always replace the 22 default module with another membership service option should the need 23 arise. 24 25 * Does its Membership Service make Fabric a centralized 26 solution? 27 28 No. The only role of the Membership Service module is to issue digital 29 certificates to validated entities that want to participate in the 30 network. It does not execute transactions nor is it aware of how or when 31 these certificates are used in any particular network. 32 33 However, because certificates are the way networks regulate and manage 34 their users, the module serves a central regulatory and organizational 35 role.