Apache Directory Server 1.0

Apache Directory Server is an embeddable LDAP server implemented in pure Java.
Our primary vision (others also outlined below) is to build an enterprise directory server platform (and its components) where other Internet services snap in to store their data within the directory so they may be managed using LDAP.
From the image above youll see the architecture is designed so services besides LDAP like DNS, DHCP, SLP and Kerberos will snap in. Other services like UDDI can also be implemented and snapped in. These services will use a common networking layer and each can be toggled on and off according to the needs of the environment.
apseda, mina, or sedang are various frameworks used for the common network layer. These services share the common network layer and back their data within the Apache Directory Servers backing stores without any network latency or going through the LDAP line protocol. NTP btw is the only exception and its there to remedy the need for time sync for replication and other time sensitive protocols like kerberos. Its implementation here is intended to prevent any dependency on external infrastructure.
Main features:
- Designed as an LDAP and X.500 experimentation platform. Plugable components and subsystems make ApacheDS extremely modular and ideal for experiments with various aspects of the LDAP protocol.
- The servers frontend is completely separable from its backend and vice-versa making it very flexible for implementing virtual directories, proxy servers and gateways to X.500.
- Several backends can be implemented and plugged into the servers partition nexus. The server supports a BTree based partition out of the box but any backing store can be used to implement a partition so long as it conforms to interfaces.
- The server exposes aspects of administration via a special system backend. LDAP can be used to manage these concerns through the system naming context at ou=system.
- Java based triggers and stored procedures are being implemented.
- Both the backend subsystem and the frontend are separable and independently embeddable.
- The server contains a server side JNDI LDAP provider as the facade for the entire backend subsystem. JNDI operations are directly translated by this provider into operations against the nexus and the target partitions storing server entries.
- The server will use JNDI as the data access API for stored procedures. This will make stored procedures functional within and outside of the server without requiring recompilation.
- The servers networking code, MINA, Multipurpose Infrastructure for Network Applications was designed for pluggable protocol providers, of all sorts and not just LDAP. MINA gives ApacheDS the ability to handle large amounts of concurrency.
- The server uses the Snickers tools and APIs for ASN.1 BER encoding and decoding. These tools are designed for a very small encoding and decoding footprint as well as for use in non-blocking servers. The chunking nature of the BER codec makes the server very efficient while handling encoding and decoding making it more resistant to DoS attacks. This layer is also pluggable with a new experimental Twix provider which is much more efficient. Of course there is the unsupported Snacc4J provider which is no longer maintained.