Features
Lotus Notes is a client-server, collaborative application developed and sold by IBM Software Group. IBM defines the software as an “integrated desktop client option for accessing business e-mail, calendars and applications on the IBM Lotus Domino server.”
The Notes client is mainly used as an email client, but also acts as an instant messaging client (for Lotus Sametime), browser, notebook, and calendar/resource reservation client, as well as a platform for interacting with collaborative applications.
In the early days of the product, the most common applications were threaded discussions and simple contact management databases. Today Notes also provide blogs, wikis, RSS aggregators, CRM and Help Desk systems, and organizations can build a variety of custom applications for Notes using Domino Designer.
The Notes client can be used as an IMAP and POP e-mail client with non-domino mail servers. Recipient addresses can be retrieved from any LDAP server, including Active Directory. The client also does web browsing although it can be configured to launch the default browser instead.
Features include group calendaring and scheduling, SMTP/MIME-based e-mail, NNTP-based news support, and automatic HTML conversion of all documents by the Domino HTTP task.
Notes’ integration with IBM’s Sametime instant messaging allows users to see other users online and conduct chat sessions with them. A chat session can be with one person or multiple people. Beginning with Release 6.5 this functionality is built into the Notes client and presence awareness is available in email and other Notes applications for users in organizations that use both Notes and Sametime.
Since version 7, Notes has provided a web services interface. Domino can be a web server for HTML files too; authentication of access to Domino databases or HTML files uses Domino’s own user directory and external systems such as Microsoft’s Active Directory.
A design client is available to allow rapid development of databases consisting of forms, which allow users to create documents; and views, which display selected document fields in columns.
In addition to being a groupware system (e-mail, calendaring, shared documents and discussions), Notes/Domino is also a platform for developing customized client-server and web applications. Its use of design constructs and code provide capabilities that facilitate the construction of “workflow” type applications (which may typically have complex approval processes and routing of data).
Since Release 5, Lotus server clustering has been capable of providing geographic redundancy for servers.
Data replication
The first release of Notes included a generalized replication facility. The generalized nature of this feature set it apart from predecessors like Usenet and continues to differentiate Notes from many other systems that now offer some form of synchronization or replication. The facility in Notes and Domino is not limited to email, calendar, and contacts. It works for any data in any application that uses NSF files, which are the standard container for data in the Notes architecture, for its storage. No special programming, tagging, or other configuration is required to enable replication.
Domino servers and Notes clients identify NSF files by their Replica IDs and keep files with matching IDs synchronized by bidirectionally exchanging data, metadata, and application logic and design. Replication between two servers, or between a client and a server, can occur over a network or a point-to-point modem connection. Replication between servers may occur at intervals according to a defined schedule, in near real-time when triggered by data changes in Domino server clusters, or on an ad-hoc basis when triggered by an administrator or programmatically.
Creation of a local replica of an NSF file on the hard disk of a Notes client enables the user of the client to take full advantage of Notes databases while working off-line — with the client synchronizing any changes when client and server next connect. Local replicas are also sometimes maintained for use while connected to the network in order to reduce network latency. Replication between a Notes client and Domino server can run automatically according to a schedule, or manually in response to a user or programmatic request. Local replicas on early releases of the Notes client did not always maintain all security features programmed into the applications, but starting with Notes 6 enforcement of application security is automatic for all local replicas.
Security
Notes was the first widely adopted software product to use public key cryptography for client-server and server-server authentication and for encryption of data, and it remains the product with the largest installed base of PKI users. Under current US export laws, Lotus supports only one version of the Notes PKI with 128 bit symmetric keys, 1024 bit public keys, and no workload reduction factor. The Domino server’s security tools also include S/MIME, SSL 3.0 support with industry standard key sizes for HTTP and other Internet protocols, X.509 client certificates, and an integrated certificate authority.
Lotus also employs a code-signature framework that controls the security context, runtime, and rights of custom code developed and introduced into the environment. With Release 5, Lotus introduced Execution Control Lists at the Client level – starting with 6, ECL’s can be managed centrally by server administrators through the implementation of Policies.
Database Security
Every database has an access control list (ACL) that specifies the level of access or rights a user or a server can have to that database. Although the names of access levels are the same for users and servers, those assigned to user determines the tasks he or she can perform in a database, while those assigned to a server determines what information within the database a particular server can replicate. Only a user or administrator with Manager access can create or modify the ACL.
To control the access rights of a Notes user, select the access level, user type, and access level privileges for each user or group in a database. You can set default entries in the ACL when you create the database. You may also assign roles if the database designer determines this level of access refinement is needed by the application.
Programming
Notes/Domino is a cross-platform, secure, distributed document-oriented database and messaging framework and rapid application development environment that includes pre-built applications like email, calendar, etc. This sets it apart from its major commercial competitors, such as Microsoft Exchange or Novell GroupWise, which are generally purpose-built applications for mail and calendaring that offer APIs for extensibility.
Lotus Domino databases are built using the Domino Designer client, available only for Windows; while standard user clients are available for Windows, Linux, and Mac. A key feature of Notes is that many replicas of the same database can exist at the same time on different servers and clients, across dissimilar platforms, and the same storage architecture is used for both client and server replicas.
