Running Linux, 5th Edition - Matthias Kalle Dalheimer [144]
We first look at what is possible using only client capabilites, without access to a groupware server, and then examine the different server solutions that are available and what addtional benefits they bring.
Basic Group Organization
Thanks to a set of established Internet standards, groupware users can collaborate not only using a single groupware server—within a single organization, for example—but also to a certain extent with partners using different groupware clients and servers on Linux or Windows. This is done by sending email messages that contain the groupware information as attachments back and forth. All the available Linux groupware suites (Kontact, Evolution, and Mozilla) support this, as do proprietary clients on Windows and Mac OS such as MS Outlook or Lotus Notes.
As an example, let's look at what ensues when you invite your friendly neighbor, who happens to still be running Windows and using MS Outlook, to your barbecue garden party on Wednesday. To do that you open your calendar to the current week and create a new event on Wednesday afternoon. (See Figure 8-46. We use Kontact in this example.) Add your neighbor as an attendee of the event and, since without him the party would be no fun, set his participation to be required. Once you've entered all the relevant information and closed the dialog, an email is constructed and sent to the email address of your neighbor. This message consists of a text part with the description of the event and an additional messsage part containing the details of the event in a certain format, which is specified in RFC 2446 and referred to as iTip.
Figure 8-46. Creating a new event in Kontact
At the receiving end, your neighbor's Outlook mailer detects the incoming message as an invitation to an event and reads the relevant information from the attachments. One attachment asks your neighbor whether he'll be able to attend and whether the invitation should be accepted, declined, or accepted tentatively. Since he's not quite sure that Wednesday might be the night of a sports event he plans to watch, let's say he chooses to accept the event tentatively. The event is then added to his own calendar inside Outlook and a reply message is constructed and sent, again containing a special iTip attachment.
Once that message makes it back to you, Kontact will inform you that the person you invited has tentatively accepted the invitation, and will enter that information into your calendar. As soon as your neighbor decides to either decline or accept the invitation, an update message will be sent and the status updated accordingly in your calendar upon receipt of that message. Should you decide to delete the event from your calendar, such an update message would in turn be sent to all attendees automatically.
The described mechanisms work not only for events, but also for assigning and sending tasks to other people and being informed when those tasks have been completed. To do that, you can add participants to tasks in Kontact's Todo List view by right-clicking on a task, selecting Edit, and then opening the Attendees tab of the dialog that pops up. Of course, this functionality is also available in other clients, such as Evolution or Mozilla; the dialogs just look a bit different.
Similar to the iTip format (or iCal, which iTip is based on), there is an Internet standard for exchanging contact information called vCard. To communicate your new street address and phone number to your grandmother, who uses Mozilla on Windows for