The Sun Java System Calendar Server was Sun's calendar (scheduling) server. The currently available version is 6.3 which is now part of the Sun Java System Communications Suite.
Users can access their calendar and task list items using a variety of clients. Web browsers will be able to access Calendar data using Sun Java System Communications Express as an HTML-based client. Microsoft Outlook users can access their calendar data using the Sun Java System Connector for Microsoft Outlook, which is not yet compatible with Outlook 2010. Mozilla Thunderbird users can add fully functional calendar access to the Sun Calendar Server to the email software by adding the Mozilla Lightning extension for WCAP (Web Calendar Access Protocol). Finally, starting in 2008, the Sun Java System Communications Suite 6 will include an AJAX-based Web client which will provide better "thick client-like" user interactions.
A useful feature of Calendar Server is the notification service. This service will send an e-mail or an SMS to the calendar owner. These messages are sent to the calendar owner if he/she has been invited to an appointment or as a reminder of an upcoming appointment. These reminders are directed to a person's cell phone by using their phone carrier's email address assigned to their phone.
The notification services are also useful for developers to implement their own software applications. Calendar reminders and change events are published to a Java Message Service using Sun Java System Message Queue.
Developers may use the WCAP interface to write their own applications which access calendars, tasks, and look up "free busy" information on users. This interface returns calendar data in a number of formats including XML and iCalendar. JSON (JavaScript Object Notation) format was added to support AJAX development in the latest patch of Calendar Server 6.3.
Sun's Java System Calendar Server has a long history, drawing technology from Sun Internet Calendar Server (SICS) and Netscape Calendar Server (NCS). The software has undergone several name changes; in addition to the above, it has also been marketed as iPlanet Calendar Server and Sun ONE Calendar Server. The code base has been carried on throughout these name changes with only feature/packaging enhancements and bug fixes.
Since 2003, the Calendar Server has been included as part of Sun's Java Enterprise System, a collection of infrastructure software applications and tools. It is also available as part of the Sun Java System Communications Suite, a smaller collection of messaging and collaboration services that includes Sun Java System Messaging Server, Sun Java System Instant Messaging Server, and Sun Java System Communications Express. Supporting server software for the Calendar Server includes Sun Java System Directory Server, Sun Java System Access Manager, and Sun Java System Web Server. The supporting software is included in the Communications Suite bundle with limited-use license rights.
Calendar Express was the original web-based client interface for the Calendar Server. This HTML client allowed Calendar owners to create appointments, invite others to meetings, and to subscribe to other calendars. The Calendar Express web-client was dropped from support starting with Sun Java System Calendar Server 6.3. This client functionality has been replaced by Sun Java System Communications Express.
The Calendar Server version 6.3 is supported on multiple operating systems including Sun's Solaris and Red Hat Enterprise Linux. HP-UX and Microsoft Windows have since been dropped from support starting with version 6.3.
Microsoft Outlook is a personal information manager software system from Microsoft, available as a part of the Microsoft 365 software suites. Though primarily being popular as an email client for businesses, Outlook also includes functions such as calendaring, task managing, contact managing, note-taking, journal logging, web browsing, and RSS news aggregation.
SOGo is an open source collaborative software (groupware) server with a focus on simplicity and scalability.
Microsoft Exchange Server is a mail server and calendaring server developed by Microsoft. It runs exclusively on Windows Server operating systems.
Microsoft Entourage is a discontinued e-mail client and personal information manager that was developed by Microsoft for Mac OS 8.5 and later. Microsoft first released Entourage in October 2000 as part of the Microsoft Office 2001 office suite; Office 98, the previous version of Microsoft Office for the classic Mac OS included Outlook Express 5. The last version was Entourage: Mac 2008, part of Microsoft Office 2008 for Mac, released on January 15, 2008. Entourage was replaced by Outlook for Macintosh in Microsoft Office for Mac 2011, released on October 26, 2010.
The following tables compare general and technical features of notable email client programs.
Outlook on the web is a personal information manager web app from Microsoft. It is a web-based version of Microsoft Outlook, and is included in Exchange Server and Exchange Online
Kolab is a free and open source groupware suite. It consists of the Kolab server and a wide variety of Kolab clients, including KDE PIM-Suite Kontact, Roundcube web frontend, Mozilla Thunderbird and Mozilla Lightning with SyncKolab extension and Microsoft Outlook with proprietary Kolab-Connector PlugIns.
The Mozilla Application Suite is a discontinued cross-platform integrated Internet suite. Its development was initiated by Netscape Communications Corporation, before their acquisition by AOL. It was based on the source code of Netscape Communicator. The development was spearheaded by the Mozilla Organization from 1998 to 2003, and by the Mozilla Foundation from 2003 to 2006.
Zimbra Collaboration, formerly known as the Zimbra Collaboration Suite (ZCS) before 2019, is a collaborative software suite that includes an email server and a web client.
Nokia PC Suite is a discontinued software package used to establish an interface between Nokia mobile devices and computers that run the Microsoft Windows operating system. Its first release was in 1997, originally called Nokia Data Suite. It was replaced by Nokia Suite and integrated into the Ovi service suite.
Network Security Services (NSS) is a collection of cryptographic computer libraries designed to support cross-platform development of security-enabled client and server applications with optional support for hardware TLS/SSL acceleration on the server side and hardware smart cards on the client side. NSS provides a complete open-source implementation of cryptographic libraries supporting Transport Layer Security (TLS) / Secure Sockets Layer (SSL) and S/MIME. NSS releases prior to version 3.14 are tri-licensed under the Mozilla Public License 1.1, the GNU General Public License, and the GNU Lesser General Public License. Since release 3.14, NSS releases are licensed under GPL-compatible Mozilla Public License 2.0.
The Sun Java System Communications Express provides an integrated web-based communication and collaboration client to the Sun Java System Communications Suite. It consists of three client modules: Calendar, Address Book, and Mail. The Calendar and Address Book client modules are deployed as a single application on any web container and are collectively referred to as Unified Web Client (UWC). Sun Java System Communications Express is included with both the Sun Java System Calendar Server and the Sun Java System Messaging Server.
Web Calendar Access Protocol (WCAP) is a protocol for remote client-server calendar access and scheduling based on the XML, HTTP, iCalendar, and vCard Internet standards.
Sun Java System Communications Suite is a collection of "Industrial-Strength" software services from Sun Microsystems. The supported platforms are: Red Hat Enterprise Linux, Solaris and Windows Server. Since Oracle acquired Sun in 2010, collection is now called Oracle Communications Unified Communications Suite.
O3Spaces is a document management system developed by O3Spaces B.V.. It is built by a team of software engineers based in the Netherlands using OpenOffice.org, StarOffice, and ODF-centric applications as enterprise office and collaboration solutions. The product is written in Java, and based on the Tomcat server with a PostgreSQL backend. O3Spaces works by providing users a single web-based team environment, with built-in search capabilities and an optional Desktop Assistant. Its search functionality is said to work across PDF, ODF, and Microsoft Office document formats. Currently Firefox, Internet Explorer and Safari are supported.
GMS (GMS) is a commercial mail and groupware server developed by Gordano Ltd. It runs on Windows, Linux, Solaris, and AIX. Originally called NTMail which was the first commercially available mail for the Windows platform, the products were rebranded to the Gordano Messaging Suite in August 2002 to reflect the support for additional hardware platforms and operating systems.
MailSite is a commercial mail server, calendar software, contact manager and collaborative software that was developed by Rockliffe Systems. It was one of the first mail servers to run on Windows NT using Internet standards when version 1.2 was released in 1996. Additionally, MailSite has been in continual development since 1996 with version 10 released in 2013, and runs on a single Windows Server as well as on a cluster of Windows Server computers. MailSite works natively with Microsoft Outlook versions 2007 to 2013 for mail, calendar and contacts without requiring any Outlook plug-ins, as well as including an Exchange ActiveSync (EAS) server for synchronizing mail, calendar and contacts with mobile devices. MailSite also works with Internet Standards-based mail clients such as Mozilla Thunderbird.