
Collaborative online office solutions
Many Cooks
Groupware solutions enable collaborative teamwork. However, conventional documents such as texts, tables, or presentations are often still created conventionally at individual workstations. Office suites for collaborative work on documents have long outgrown their infancy. This article examines the possibilities offered by the individual office packages.
Workflow
Office solutions for collaborative work support very flexible use. On the one hand, they extend groupware packages like EGroupware, Zimbra, or Kopano. On the other hand, they also integrate into self-hosted cloud solutions such as Nextcloud or ownCloud. Some network-attached storage (NAS) systems also come with suitable apps in their software stores. You don't necessarily need dedicated servers for collaborative editing. Sometimes the office packages run both in the cloud and on the local workstation and simply synchronize the data.
In all cases, collaboration is not limited to editing documents. Users can also insert comments, to which other users can respond. A module for versioning completes the package. If desired, office solutions save different editing states of a document and reconstruct them again as needed. Users always have access to older versions of documents, which helps them to compare documents, among other things.
Today, in larger work environments, people use a variety of office formats, or employees simply exchange many documents with customers outside their own IT infrastructure. In such cases, the quality of the filters for import and export is critical. The more sophisticated the filters are, the less manual rework is required.
However, the use of proprietary software entails some limitations. For example, documents that are available in the various Microsoft (MS) formats and contain macros do not usually run correctly in the popular office suites of other manufacturers. Because macro languages vary, Microsoft macros cannot be executed in non-MS packages.
Collabora Online
Collabora Online [1], which is based on LibreOffice Online, is used in numerous groupware solutions as the standard package for collaborative work on office documents. The web-based suite consists of word processing, spreadsheet, and presentation modules (Figure 1). Collabora Online also works with locally hosted cloud solutions such as Nextcloud or ownCloud. Regardless of the module used, Collabora Online offers a largely identical interface and is therefore very easy to use.

With the focus on collaborative work, the British developers (Collabora Ltd.) threw some rarely used functions of LibreOffice overboard and added special functions that are important for teamwork. Because Collabora Online supports locally hosted cloud services, the data processed with it remains under the control of the respective users and does not end up on the servers of external companies. (See the "Hosted Office: What to Consider" box for more information.)
File Formats
Another strength of Collabora Online is that it supports numerous third-party formats. This feature allows users in heterogeneous environments to modify documents that the originator created in another office suite. In most cases, Collabora Online loads documents from third parties for further processing without any issues.
As already mentioned, this functionality does not apply if the documents contain executable macros. Because the office suites available on the market all use mutually incompatible macro languages, Collabora Online imports such documents but does not execute the macros they contain. This shortcoming also has an advantage, however, in that malware integrated in macros, which regularly causes problems in the enterprise, is suppressed in Collabora Online.
Collabora Online processes documents in the free open document formats as well as the current and older Microsoft formats. The software also supports PDF across all modules. If required, users can also convert text files to the ePub format for displaying appear on ebook readers or with desktop software for reading ePub files.
Comments
Comments play an important role in collaborating on documents. In Collabora Online, users can use Insert | Comment to enter their own comments in a small input window. After clicking on Save, the comment is glued to the entry location and shows the author and time stamp.
Collabora Online positions the comment field itself in a separate column to the right of the document display. When a user clicks on a comment, a line points directly to the corresponding passage in the text, making the area to which the comment refers clearly visible. Using a small three-line (hamburger) menu on the right side of the comment window, other users now reply directly to the comment. The answers appear below the first comment. The comments can be deleted, resolved, or edited within the options of the menu.
Versions
Collabora Online has a version history that makes it possible to trace the creation process of a document and can be put into effect via Edit | Track changes. The user starts the version recording by activating the Recording option.
Collabora Online then creates separate entries in text boxes to the right of the document display in a column for each modification of a document. This shows the type of change, the time, and the person who made it (Figure 2). In the document, the relevant changes appear in different colors, but only until the user clicks on Accept change in the text box. Then the text box disappears and the document displays the area as before.

Etherpad and Ethercalc
Etherpad [2] and Ethercalc [3] are two separate, independently developed office applications for word processing and spreadsheet applications, respectively. As a unique selling point, the two programs written in JavasScript let several users edit documents on the intranet in real time and simultaneously. The modifications appear in real time on the screens of all participants. Both programs use a server that provides the user interface in the form of a web page. The individual clients therefore do not need any special native software.
Word Processing
The user opens the Etherpad editor in the web browser and creates a new pad here. After a short loading time, the page display appears with a sample text. Using the URL shown there, the user then invites other users to work on the same text. Etherpad assigns a different color to each invited user. Modifications to the text appear in this color. This allows each participant to immediately assign changes to the text to the appropriate author.
Every change appears on all involved workstations in real time. Additionally, the software displays line numbers so that readers can quickly locate specific points in the text. This numbering can also be switched off by the user if desired.
Communication
Etherpad has a small chat module for communication, which is hidden in the settings menu. The user can access the menu by clicking on the gear symbol in the upper right corner of the browser window. From the menu, you can activate the Show Chat and Users option with a slider, which displays a new vertical bar on the right side of the browser window. The bar contains the communication history and an input line at the very bottom (Figure 3). On low resolution screens, Etherpad displays the communication in a small separate window to not limit the workspace.

Foreign Language
Etherpad has only rudimentary import and export filters, which the user cannot extend with plugins. Currently, it supports only import and export of simple text or HTML documents. Where third-party formats are involved, the developers recommend using LibreOffice or another office suite to first convert the source format into a form readable for Etherpad. However, because Etherpad supports relatively few attributes for text formatting, it is not useful for sophisticated documents, such as ones that contain tables, formulas, or images.
Versions
To keep different versions separate, Etherpad also has an editing history. Editing states can be saved and played back via a timeline. Each change appears as a separate edit version. Saved versions are marked with an asterisk in the timeline to allow users to jump quickly to them.
Users can save individual versions by clicking on the asterisk in the top right corner of the browser window toolbar. To the left, you then call up the version history by clicking on Editing history. The software switches to the version view, which shows the timeline at the top and the document below (Figure 4).

Jumping back in the timeline also updates the assigned version of the document. The user can also play back the entire edit history of the document via the Play button. Clicking on the Back to Pad button takes the user back to edit mode.
Ethercalc has a far larger feature set than Etherpad and also a menubar – although this is admittedly fairly rudimentary. Ethercalc also implements teamwork via individual URLs, which the respective user calls up in the web browser.
After typing the IP address of the server followed by the port number 8000 into the URL box, you are taken to a start page where you can either create a new spreadsheet or import an existing one. Ethercalc supports CSV, ODS, and XLSX files. In the test, however, it was unable to correctly read several simple ODS sample documents, making them unusable (Figure 5).

Communicative
Ethercalc does not have a chat module, but participants can talk to each other via a comment function. To do this, you can click on the Comment entry at the top of the menubar, which opens a multiline field for free-text input. After typing in the comment, press the Save button.
Please note that the comment function is cell sensitive. To enable other users to understand comments, the author of the comment must place the cursor in the table cell to which their comment refers.
In the table itself, Ethercalc does not mark comments and does not indicate them by symbols or color changes. To view comments, team members instead must explicitly select the Check menu item in the table view. Only then does Ethercalc list all the comments and show the cell number in front of each comment (Figure 6). Other users assign individual remarks using this number. The software adopts the comments in real time.

Google Docs
Docs, developed by the Internet giant Google, is a component of Google Docs, Sheets, and Slides. The office suite includes programs for managing texts, tables, presentations, drawings, and forms [4]. The package is exclusively available as a SaaS solution, and users need a free account with Google. Google Docs automatically saves the documents on Google Drive, a cloud-based storage solution also operated by Google. Google Docs exclusively runs in standard web browsers and can therefore be used across platforms. There are separate apps for widely used smartphone operating systems.
Teamwork
Google Docs offers numerous functions for collaborative work. Several users can edit a document simultaneously, and all users can track changes. To share a document, the author first presses the Share button (Figure 7) top right in the browser window. This opens a small dialog, through which to invite other users to edit the document.

Two options are available. If the owner of the document sends a specially generated link, all users who have this link are allowed to view the document. However, you cannot edit it in this mode.
Using the option Share with Persons and Groups, the owner can invite specific persons or groups to collaborate on the document. These people also will need a Google account. After entering the email address, Google sends a link it generates to the recipient. The recipient then starts Google Docs by clicking an activation button in the email and calling up the corresponding document.
Various options for working on the document in a team are displayed at the top right in the browser window. A speech bubble icon lets you send and view comments. To the left of this, the names of the users who are currently working on the document online appear in the form of short symbols. They can also be addressed directly via the chat function.
Comments
A mouse click on the Open Comment History button shows the previous comments. You can add your own comments by clicking on the Comment button. Once you do this, the term in the document where the cursor is positioned will appear with yellow highlighting, and Google Docs will open the comment area vertically on the right. You can then post your comment in a field for free-text input.
After clicking on the Comment button, the comment is displayed in real time for all participants. Google stores these flags in the document in color. In this way, all recipients can see at a glance to which part of the document the comment refers.
If a user wants to mark a comment as edited or resolved, they simply click on the check mark to the right of the comment window. Google Docs will then hide this note in the comment column.
Chat Function
Users working on the document may also want to chat to each other. This option is especially helpful if individual participants want to exchange information beyond the scope of the comment function.
The chat appears in an ongoing session when a user clicks on the Show Chat button to the right of the respective participant. You can then type your message in an input box that appears in another column on the right side of the browser window (Figure 8). Because Google Docs maintains the chat column independently of the document and the comment column linked to it, problems can occur – especially on screens with lower resolution. The user then needs to scroll back and forth to view the columns to the right of the document.

Formats
Google Docs can handle various file formats. In addition to RTF, these include ODT and DOCX for word processing, XLSX and ODS for spreadsheets, and PPTX and ODP for presentations. Docs also supports PDF files, and users can also save individual slides of a presentation as JPG, BMP, or PNG images.
The formats can be imported and exported. In some cases, however, this requires manual reworking of the document, because Google Docs, like other office packages, does not support all attributes of the third-party formats.
Because the suite stores all the data in the Google Cloud, users need to store files to be imported in the cloud using the File | Open | Upload menu. To download a file in progress in a specific format to a local workstation, access the File | Download dialog. Then select the desired target format and destination in a selection box.
Versions
Google Docs also offers users a version history, which is available in all modules in the File | Version History menu. In this submenu, you can save the current version of the document, to which you then assign a meaningful version name in an overlapping window.
To access the version history, select the View version history option. On the right side of the window, a tabular column shows the saved versions of the document. Then select an entry from this list. Google Docs displays the corresponding version on the left side of the browser window and visually highlights changes to the document compared to the previous version. In this way, users can see at a glance what changes have been made.
Onlyoffice
Onlyoffice [5], developed by Latvia's Ascensio System SIA, is an extremely flexible office package that adapts to almost any requirement profile. The Onlyoffice Online Editors variant runs both on on-premise servers in the enterprise and in a cloud environment as part of a third-party-hosted SaaS solution. There are also integrations with traditional cloud storage systems, such as Nextcloud, ownCloud, Pydio, and Seafile, as well as with LMS systems, such as Moodle, or various content and process management platforms, such as Alfresco, Plone, or Agorum.
Onlyoffice Online Editors run in the web browser; a native client is not required. This makes the software ideally suited for heterogeneous infrastructures with clients running different operating systems.
In the form of Onlyoffice Desktop Editors [6], the package also offers a competitor to the conventional locally installed office suites. It shares a uniform interface with the browser-based online package and can also be connected to on-premise servers. Thus, users receive a similar range of functions in the locally installed version to that of the browser-based version.
Third-Party Formats
Onlyoffice internally works with the Office Open XML (OOXML) format developed by Microsoft. However, the software converts older Microsoft formats, ODF as well as PDF, HTML, or RTF.
When uploading a document to Onlyoffice Online Editors, users can also specify individually for all files whether they want to store files in the current source format. If you check the box to enable this function, the software saves the respective file in the cloud in the original file format in addition to the OOXML format.
When downloading a file, you can use the Download or Download as options in the file manager. In the case of a conventional download, Onlyoffice saves the marked file in OOXML format on the local workstation. The Download as option additionally offers to convert to another supported file format in a selection field (Figure 9).

The results of the conversion from OOXML to ODF are impressive even with more demanding layouts. In most cases, however, you will need to make some simple manual adjustments to the documents. This is also true for converting in the opposite direction.
Teamwork
Onlyoffice Online Editors supports a collaborative work approach on documents through individual File Sharing. The user can share any file in the file manager by clicking the corresponding button. It can be found to the right of each file name. The software supports the release for individual users but also for user groups.
The program displays a small dialog where you stipulate the users and groups with whom you want to share a file. In the Document Editor, you will also see the Collaboration option in the menubar (Figure 10). This option provides a wealth of options for editing the document with several users.

Editing Modes
Onlyoffice supports two modes for editing documents collaboratively. In the Collaboration ribbon bar, you can click on Set Collaboration Edit Mode to choose whether to save all changes immediately or trigger saving manually. If you enable Fast mode by checking this option, the software automatically saves all changes in real time. The Formal option, on the other hand, expects the user to save the document manually in order to synchronize it with the other editors.
Comments
Onlyoffice also comes with a comment function. You can access this via the Add Comment option, which can be found both in the Collaboration menu and in the right-click context menu that appears at the current position in the document.
Onlyoffice then displays a window to the right of the document view. This is where you type your comments. The software positions the individual annotations, even in multiple-page documents, at the same height as the cursor position to which the annotation refers.
Users who are editing the document can respond directly to a comment without having to add a new comment window each time. To do this, simply click on the Add Response option and then type a text in the input box. A longer dialog prompts a chronological view so users can grasp the complete comment history at a glance.
Changes
Onlyoffice not only tracks modifications to documents but also presents them visually in different ways. In the Collaboration menu, you will find the Display Mode option. Markup mode shows all changes with different font attributes and in different colors. Markup mode is the default for collaborative editing of a document.
Final mode accepts all changes and displays the document without any previous editing status. Original mode lets a user restore the original state of a document. In this case, the software will not accept any changes.
For multiple-page documents, you can also use the two buttons Go to previous change and Go to next change in the document to jump backward or forward. Accept and Reject let the document owner confirm or reject any edits made, always referring to the current change.
Version History
Onlyoffice also offers a version history. The button for this is found in the Collaboration menu; pressing it opens a column on the left of the document view. Onlyoffice lists the individual versions of the document one below the other. The history arranges the versions chronologically top-down and also shows the editors.
Clicking on one of the version entries opens the corresponding version on the right side of the window. To switch back to edit mode, click on the Close History link at the top left in the version column.
Chat
The Onlyoffice chat function is activated via a separate entry in the Collaboration menu. The software then opens a column to the left of the document view; at the bottom it displays an input field for text messages. The latter sorts the messages in the column by submission time, including the responses submitted by the other members of the team. To end the chat and make the column disappear again, press the Chat button at the top right in the ribbon bar again.
Conclusions
All of the office suites looked at here offer the typical set of functions for collaborative working (see Table 1), but they serve different target groups.
Tabelle 1: Collaborative Work with Documents
Collabora Online |
Etherpad / Ethercalc |
Google Docs |
Onlyoffice |
|
---|---|---|---|---|
License |
MPL |
Apache 2/MPL |
SaaS |
AGPLv3 |
Functions |
||||
Modules |
Text, tables, presentation |
Text, tables |
Text, tables, presentation, drawings |
Text, tables, presentation |
Web-based client |
Yes |
Yes |
Yes |
Yes |
Native client |
No |
No |
No |
Yes |
On-premise server |
Yes |
Yes |
No |
Yes |
Externally hosted cloud solution |
Yes |
No |
Yes |
Yes |
Integration into groupware |
Yes |
No |
Yes (Google services) |
Yes |
Third-party formats |
PDF, RTF, HTML, DOCX, XLSX, PPTX, ODT, ODS, ODP, TXT |
TXT, HTML, CSV, ODS, XLSX |
PDF, RTF, HTML, DOCX, XLSX, PPTX, ODT, ODS, ODP, TXT |
PDF, RTF, HTML, DOCX, XLSX, PPTX, ODT, ODS, ODP, TXT |
Collaborative Functions |
||||
Comments |
Yes |
Yes |
Yes |
Yes |
Chat |
No |
Yes/no |
Yes |
Yes |
Version history |
Yes |
No |
Yes |
Yes |
Etherpad and Ethercalc focus on user data sovereignty, whereas Google Docs, as an integral part of the Google universe, also uses its cloud storage and, due to its close integration with other Google services, is not a genuine option for privacy-conscious users.
Collabora Online and Onlyoffice, however, appear to be solid all-rounders, with the Onlyoffice package offering a more structured interface for collaborative functions.
All packages still show weaknesses when converting third-party formats. In many cases, after importing and exporting from and into other file formats, manual rework is required to put the document back into shape on the target system. Although simpler texts and tables can usually be converted without problems, more complex documents usually require intensive post-processing.
Macros pose a totally different problem. They are usually limited to a certain office format and cannot be used in others. Therefore, companies and organizations need to mandate a file format, if possible, even in heterogeneous environments.