FAQ MLUconf/en

General Questions

What kind of video conferencing systems are available at the MLU?

The MLU offers two systems: MLUconf and Webex. MLUconf is fully accessible to both students and MLU-staff. It is based on the open source system BigBlueButton and runs on our own server, ensuring complete compliance with data protection regulations.

On Webex, only MLU staff members have access to configuring and starting a conference. Please refer to our Wiki for a brief comparison between MLUconf and Webex.

What is the maximum number of participants for a MLUconf meeting?

After testing, we have found that a meeting with a maximum of 250 participants is possible. To ensure this, please avoid private chats and the use of more than one camera. Additionally, only the presenter should actively use their microphone and camera. Instead of using the screensharing option, please upload the presentation slides for better performance.

Meetings held with Stud.IP and ILIAS are automatically limited to 250 participants. However, meetings set up directly on mluconf.uni-halle.de do not have this limitation, theoretically allowing for more than 250 participants.

Video conferences with all participants actively using both their microphones and their cameras can accommodate up to 25 people. If this number is exceeded, connectivity issues may arise. Explanations for this are provided in the general documentation of BigBlueButton, the open source software utilized for MLUconf.

Concerning accessibility: Do screen readers work with MLUconf?

Yes, MLUconf and its software BigBlueButton are compatible with screen readers. We recommend using the Firefox or Chrome browser. Tutorials for using a screen reader with BigBlueButton can be found on this [site].

For the hearing-impaired, automatically generated subtitles can be enabled. For this, click on the little ‘settings’ symbol and select the subtitles-function. However, please note that the automatically generated subtitles may not be reliable.

When should I use which system?

If you are a member of the MLU, we recommend using MLUconf. Its system is tailored to the needs of the MLU, designed to match the common MLU colours, and hosted on our own servers to ensure compliance with data protection regulations.

Students
Students can only use MLUconf, while Webex is exclusively available for staff members.

Lecturers
MLUconf should be the primary platform for video conferences. Additionally, Cisco Webex can be used by staff members.

The meeting should take place during the course.

• Please use the MLUconf plugin on Stud.IP or ILIAS

External participants should be able to easily access the meeting.

• Set up your meeting on MLUconf at mluconf.uni-halle.de and share the link with the participants.

The conference has over 100 attendees.

• Consider using Webex for meetings as it can accommodate up to 1000 participants without connectivity issues. MLUconf meetings can support up to 100 participants without connectivity problems if the webcams are not used. The ITZ is still testing the definite maximum on MLUconf.

The conference should be hosted on an internal MLU server.

• Use MLUconf for meetings as they are hosted on our own servers, ensuring compliancy with data protection regulations.
• Webex is a software developed by Cisco Systems. Its servers are located in different countries.

What are the technical requirements for MLUconf?

To actively participate in a video conference, a stable internet connection, microphone, and web-camera are required. For optimal speech quality and to reduce background noise, it is recommended to use a headset. Web-cameras are often integrated into tablets or notebooks.

Does MLUconf offer long-term meetings where all the material remains in the online room?

Currently, there is no option to set up long-term or permanent meetings where participants can leave the room and return the next day to find all the material and the chats still available.

Who do I contact if I have any questions or problems?

Please email mluconf@itz.uni-halle.de with your details:

• When the error occurred
• What type of video conference was held
• If possible, the concrete error message
• Which node you were on (you can find the node in the address bar of your browser, e.g. node5.conf.uni-halle…)
• Which system you are using (browser, software system)
• Which network you were using (MLU w-lan, an external network) and if possible your IP-address

We will get back to you as soon as possible. We guarantee a close support from the ITZ and LLZ.

Current fault report can be found here.

Access to MLUconf

Which login data is required for mluconf.uni-halle.de?

Students: Please visit https://mluconf.uni-halle.de and use your Stud.IP login details.

Lecturers and other members of the MLU: Please use your central university login details (e.g. for mail and W-LAN) which consists of your 5-digit user ID and your password. If the password is not accepted at mluconf.uni-halle., a new password must be set in the 'Serviceportal'. Please note that this new password will then apply to all central services.

If you are a guest lecturer and only have access to Stud.IP, please contact support@elearning.uni-halle.de for assistance.

Can external users who are not members of the MLU use MLUconf? How can I invite guests to my meetings?

External users can join any meeting using a link, provided that the meeting was not created using Stud.IP or ILIAS with the guest function disabled (please refer to “When should I use meetings with Stud.IP and ILIAS?” for further information). The invitation link can be found at mluconf.uni-halle.de in the specific room under “Invite participants” or in the room settings on Stud.IP/ILIAS.

External users have the permissions assigned to them by the presenter/ moderator (s. Functions in MLUconf).

Is it possible to add external users as moderators before a meeting?

This is only possible in a meeting created on Stud.IP. There you can find a specific link for moderators in the section “Data protection settings”.

Can external users create an account on MLuconf?

No, external users can only participate in MLUconf meetings to which they have been invited with a link. They cannot create or start their own video conferences. If it is necessary for external users to create their own conference room, they must use Webex. For temporary access to Webex, please contactwebex@itz.uni-halle.de.

Guest accounts can fully utilize the MLUconf service.

For information on guest membership at the MLU refer to:

Can I join a meeting by dialling in with a telephone?

No, this is not possible at the moment. This function is still in progress.

When should I use meetings with Stud.IP and ILIAS? When should I create a meeting directly at mluconf.uni-halle.de?

Meetings created on Stud.IP or ILIAS can only host a limited group of participants. These metings can only be joined by the people who are enrolled in the specific Stud.IP course. This applies to ILIAS es well. Even if an invitation link is sent, it can only be used by those who are part of the course.

On the other hand, meetings created at https://mluconf.uni-halle.de/ can be utilized by external participants as well. All users with the invitation link can join the meeting.

Internet Connection, Audio, and Video

recommended test sites Bandwidth: http://speedtest.net WebRTC: https://webrtc.github.io/test-pages/, in Firefox, enter "about:webrtc" into the search bar official test installation from BigBlueButton https://test.bigbluebutton.org/

What bandwidth is required to use MLUconf?

This depends on the number of participants and the type of meeting. MLUconf offers different opportunities for communication and exchange, resulting in different types of conference meetings that can cause varying levels of CPU and net load. This not only effects the MLUconf server but also the internet connection of the participants, who may need to share their internet connection with household members or neighbours.

The official BigBlueButton documentation states that a minimum upstream bandwidth of 0,5 Mbit/s (500Kbit/s) and a minimum download bandwidth of1 Mbit/s are required. The upstream bandwidth is used for data transfer to the BigBlueButton server. It is important to note that these are not fixed requirements and the necessary bandwidth may vary depending on the type of communication used by the participants. For instance, if the participants do not use their webcams, less than 0,5 Mbit/s may be sufficient.
To check your bandwidth, visit http://speedtest.net.

As a presenter, it is important to have a high bandwidth for optimal performance of functions such as screen sharing, which require larger amounts of data to be transferred per second. The following functions are listed in order of the amount of server load they cause:

1. Presentation + audio transfer of the presenter
2. Presentation + audio and video transfer of the speaker
3. Screen sharing + audio transfer of the presenter
4. Screen sharing + audio and video transfer of the presenter
5. In addition to 1-4: audio and/or video transfer of one participant (e.g. a question)
6. Audio conference: all participants have their microphone enabled and take turn speaking
7. Panel discussion: just a few participants share their audio and video while everyone else silently follows the discussion
8. Video conference: all participants share their audio and video

(Source: Johannes Gutenberg University Mainz)

What options does the presenter have to reduce the required bandwidth and improve the transmission performance?

Consider which functions are really necessary for your meeting. Do all participants need use their cameras? Less video transmission requires less bandwidth. Can you upload a presentation instead of sharing your screen? Screen sharing requires a lot of bandwidth, while the presentation and the whiteboard requires significantly less.

To improve your audio quality, use a headset and mute your microphone when not speaking. Ask the participants to do the same.

How can I participate in MLUconf meetings with a poor internet connection?

To avoid connectivity issues, refrain from using VPN during meetings.
If you are at home, it is recommended to connect your PC to your router using LAN to ensure that your W-LAN is not causing problems due to multiple users. MLUconf provides an option to reduce the data volume during transfer. To utilize this, access the settings in the digital conference room. Click on ‘reduction of data transfer’, where you can disable your own screen sharing and video transfer. This will prevent your webcam from being shared and other participants’ videos from being displayed. Remember to mute your microphone when not speaking.

During the meeting you should refrain from filesharing, streaming, etc.

What browser should I use for online meetings?

For optimal performance, we recommend using the latest version of Mozilla Firefox, Google Chrome, or Chromium. Microsoft Edge from version 83 is also a viable option.

Currently, we do not recommend the Safari browser for MLUconf meetings due to frequent audio and video issues.

Can I use MLUconf with mobile devices such as a tablet or smartphone?

Yes, MLUconf is compatible with Android or iOS mobile devices. Please ensure that you are using the latest version of your browser.

What should I do when my microphone, camera, or screen sharing function suddenly stops working?

This can have multiple reasons. One possibility is connectivity issues. It is important to note that only one software on your PC can access your camera, so check if another app is currently using it. If you experience a sudden disconnect, the simplest solution is usually to restart your PC. Additionally, you can try switching your browser.
MLUconf utilizes the WebRTC standard (Web Real Time Communication) for real-time sharing of audio, video and desktop. This standard is widely supported by most browsers and does not have specific requirements. Your browser just needs the permission to access the webcam, microphone, and the speakers.

To test WebRTC functionality for your browser and detect possible errors, use the online test at https://webrtc.github.io/test-pages/. Firefox users can access this test by entering "about:webrtc" in the search bar.

What should I do if I cannot use/ enable my microphone?

It could be that your data protection settings of your system software need to be adapted by explicitly allowing a specific browser to use your microphone.

Windows 10

Enter “Data Protection Settings” into the search bar (usually in the bottom left corner). Alternatively, you can open your settings and go to “Privacy”. Under “Microphone” the utilization of your microphone on your device needs to be enabled, as well as the access of your apps. Check if your browser is listed under the apps that have access to your microphone.

MacOS

Go to your data protection settings: System settings > Security > Data Protection. Go to ‘Microphone’ and check if your browser has access to your microphone. Safari does not have to appear in that list. If this does not solve the issue, please check the page authorisation of your browser:

• Chrome: Settings > Privacy > Website settings > Microphone
• Firefox: Settings > Privacy > Authorisation
• Microsoft Edge: Settings > Website authorisation > Microphone

iPhone/iPad

• Open ‘settings’
• Go to the settings for Safari
• Settings for Websites > Microphone
• Authorize the access

What should I do if I cannot enable my camera?

You may need to change some privacy settings in your system software to allow your browser to use the camera.

Windows 10

To access your privacy settings, either use the search bar or navigate to the 'Privacy' section in your settings. In the 'Camera' section, ensure that both the camera has access to your apps and the apps have access to your camera. Also, make sure that your browser is listed among the apps that can access your camera (e.g. Google Chrome or Firefox).

MacOS

To access your privacy settings, navigate: system settings -> security -> privacy. Select ‘camera’ from the options on the left-hand side. Check if your browser has access to your camera. Note that Safari does not have to appear in the list. If the issue persists, ensure that your connection is correctly encrypted (no yellow exclamation mark on the lock symbol) and that you are using the most up-to-date version of your browser. If all this is provided, please check the authorisation in your browser:

• Chrome: Settings > Privacy > Website Settings > Camera
• Firefox: Settings > Privacy > Section ‘Authorisation’
• Microsoft Edge: Settings > Website Authorisation > Camera

If one site is not allowed to access your camera, you will receive the report “NotAllowedError: The request is not allowed by the user agent or the platform in the current context.”

If you authorize the use of your camera, click on ‘remember settings’. This will allow your browser to automatically authorize the camera use when access is requested again.

Why do other participants only hear me delayed, cut off, or not at all?

This can have multiple reasons. Is your microphone functioning correctly? Can you hear yourself during the ‘Echotest’? It could also be due to low bandwidth (refer to FAQ “What Bandwidth is required to use MLUconf?”). Additionally, ensure that you have the latest version of your browser.

Another possible source of error is the speaking volume. The system may not transmit sound if the volume is too low due to internal throttling. This can cause delays, interruptions, or no sound at all. Check your microphone level and adjust it as needed.

Microphone level in Windows 10:

System Settings > Sound Settings > Section ‘Input’ – Device Properties. There you can adjust the volume of your microphone. Microphone level in MacOS: System Settings > Sound > Input > Adjust Volume

If all your settings are correct and the others still cannot hear you, your microphone may be muted in the Windows audio settings. To check, go to: System settings > Sound Settings > Section ‘Input’ – Device Properties > Additional Properties > Tab ‘Level’. Ensure that the speaker symbol is NOT be crossed /deactivated.

What do the Error Codes Mean?

2001: Media server is offline

The cause of this error is currently unclear. It affects the camera connection and the screen sharing option. However, a conference can still be held without these functions. Nevertheless, if you encounter this error, please contact mluconf@itz.uni-halle.de. and provide the following information:

• When the error occurred
• What video conference it was/ the name of the room
• Which node you were on (check your address bar, e.g. node5.conf.uni-halle…)
• Which system you use (browser, system software)
• Your network (MLU W-LAN, external network) and, if possible, your IP address

If the error occurs, try switching into another MLUconf room or create a new meeting room in Stud.IP and try holding your meeting there.

1020: Media cloud could not reach the server

This error may indicate that your router’s firewall is too restrictive and blocks data flows when you attempt to enable your webcam or your screensharing. Your browser is unable to establish a video connection to the meeting.

If you receive this error code in a larger meeting with multiple audio and video streams, it could be that the MLUconf server is at capacity and cannot accept all video streams. If this is the case, please contact mluconf@itz.uni-halle.de and provide the following information:

• When the error occurred
• What video conference it was/ the name of the room
• Which node you were on (check your address bar, e.g. node5.conf.uni-halle…)
• Which system you use (browser, system software)
• Your network (MLU W-LAN, external network) and, if possible, your IP address

If the error occurs consistently, we recommend trying to create a room on the official BigBlueButton testing site. If everything works well there, the problem is likely not related to your device or your internet connection.
To improve your connection to MLUconf, consider switching to a different browser and ensuring it is up to date.

Additionally, try connecting to MLUconf using a different network, such as a VPN or a mobile hotspot.

1004: Incompatible SDP

This error message suggests that your browser’s security settings prevent access. Try using the standard security settings. If you have additional security extensions, such as adblockers, privacy badgers, or NoScript, please try deactivating them while using MLUconf.

If this does resolve the issue and you were previously able to use MLUconf, consider whether you have installed any programs or add-ons that may have affected your browser. If so, please uninstall them.

1006 bzw. 1010 : Call timed out

This error message is related to an unstable internet connection. If the error persists, try switching to a different connection (such as VPN) and/or reducing the amount of data being transmitted.

To reduce data usage, MLUconf provides different options:

• To activate data reduction:

settings (the three dots in the top right corner) > settings > data reduction > deactivate cameras and screen sharing

This will prevent the transmission of videos and screens from other participants. The setting only affects your view.

• If you have to participate with your camera, choose the option to reduce the camera quality

If this does not resolve the issue, try switching your browser.

1007: ice negotiation failed

This error occurs when the server and client are unable to establish a connection. This issue is most common with the Safari browser. If you are using Safari, try switching to an up-to-date version of Chrome, Firefox, or another Chromium-based browser.
It is also possible that your router’s firewall is blocking the connection or that the network address translation (NAT) is enabled, especially if you are using multiple connected routers. Please disable these settings during a meeting.

If these settings are disabled and you are still receiving the error message, please contact mluconf@itz.uni-halle.de and provide the following information:

• When the error occurred
• What video conference it was/ the name of the room
• Which node you were on (check your address bar, e.g. node5.conf.uni-halle…)
• Which system you use (browser, system software)
• Your network (MLU W-LAN, external network) and, if possible, your IP address

You can also attempt to connect via VPN to participate in the online meeting.

1002: Could not make a WebSocket connection

If the WebSocket connection has failed, it is possible that the transfer protocol has been blocked by your firewall or that the server has failed.

If this does not apply, please contact mluconf@itz.uni-halle.de and provide the following information:

• When the error occurred
• What video conference it was/ the name of the room
• Which node you were on (check your address bar, e.g. node5.conf.uni-halle…)
• Which system you use (browser, system software)
• Your network (MLU W-LAN, external network) and, if possible, your IP address

You can also attempt to connect via VPN to participate in the online meeting.

Before the Meeting

How to prepare for an online meeting?

Ensure that your internet connection is stable and that your microphone and camera are functioning properly. For optimal stability and reliability, we recommend using a LAN connection.

How long will uploaded presentations be saved before the meeting?

Do not upload your presentation more than two hours before the meeting. After the upload, log out of the meeting in the top right corner. Do not close the window or end the meeting, as your presentation will not be available if you re-enter the online room.

During the Meeting

Can I record my MLUconf meeting?

Yes, meetings can be recorded. For further information, please refer to Portal:Onlinebetrieb/Synchrone Onlineformate/Audio- und Videokonferenzen durchführen/Aufzeichnungen in MLUconf.

What is the maximum number of participants who can activate their cameras?

It is recommended that no more than twenty cameras actively used. Depending on the connection, performance issues can still occur even before that limit is reached. This is why we recommend that only the moderators of the meeting should use their camera.

Can I specify the number and identity of participants in my meeting?

Yes, as the creator of an online room or the presenter of the meeting, you can save a list of participants. To do so, click on the settings symbol located above the list of participants and select 'Participant administration'. From there, you will be able to save the list of participants.

Can I conduct a survey during a meeting? Will that survey responses be anonymous?

Yes, you can conduct a survey. For detailed instructions, please refer to our wiki. The results of that survey are not anonymous, as the presenter can see the initials of the participants next to their answers.

The results can be shared with the participants. Once the meeting ended, the results are not available any longer.

Does MLUconf have an option to automatically generate subtitles?

No, MLUconf does not have an automatic speech recognition to display subtitles below the speaker’s video. However, the moderators of the meeting can create an additional note section where meeting attendees can write translations or transcripts.

Can I use emojis in the chat?

BigBlueButton does not have this function. Instead, you can use the emojis provided by your software system.

Windows: [windows key] + [.]

MacOS: [command] + [control] + [space]

After the Meeting

Who has the authority to conclude a meeting?

Online meetings can be ended by creators, presenters, or moderators. Once the meeting has ended, all participants will be removed from the online room.

If the creator, presenter, or moderator simply logs out, the meeting will continue.

Will the presentations be available after the meeting?

No, will not be available.

Will the chat history be available after the meeting?

No, you have to manually save the chat before concluding the meeting. (Chat window > settings > save)

What data will be saved?

For statistical purposes the time and number of participants will be recorded. There will not be any record of the specific participants, the content or personal data such as the chat history or the presentation.

Presentations and Screen Sharing

I am using the Safari browser and screen sharing does not work

To avoid any issues with screen sharing, we recommend using a different browser. Several versions of Safari browser have been known to cause problems with this feature, and Safari mobile does not support it at all.

For MacOS systems: Please ensure that the screen sharing option is enabled for your browser in your system settings. To do this, go to your system settings, then select Security and Privacy. In the table on the left, navigate to ‘screen capture’ and enable both Firefox and Chrome.

I cannot share my screen. The button for this function is not displayed.

Please ensure that you have presenter rights for the meeting. You can identify this by your icon: as a presenter, you will have an icon with rounded corners and a presentation icon in the top left corner. We recommend using an up-to-date version of either Firefox or Google Chrome when using MLUconf. Screen sharing also works with Microsoft Edge version 83 or higher. Please note that the Safari browser does not support the screen sharing option.

MacOS systems: Please ensure that the screen sharing option is enabled for your browser in your system settings. To do this, go to your system settings, then select Security and Privacy. In the table on the left, navigate to ‘screen capture’ and enable both Firefox and Chrome.

I cannot share my screen. I get the message that I do not have the necessary authorisation for screen sharing.

Please ensure first that your browser is up-to-date. We recommend the use of either Firefox or Chrome for MLUconf.

It is likely that the issue is that your browser does not have the authorization to share your screen. Similarly, to your microphone and camera, you have to authorise your browser for this. Your browser will typically prompt you with a pop-up message asking for permission to share your screen. If you do not receive a pop-up message, authorize your browser in your system settings or your browser settings.

Which mobile devices support screen sharing?

The screen sharing function is supported on Android 6.0 or higher. On iOS 12 or higher you can use screen sharing on the iPhone 6s, iPad Air2, iPad mini 2019, iPod Touch 7th generation or on all newer devices.

However, please note that screen sharing is not supported on mobile versions of Chrome Mobile and Safari Mobile browsers. We recommend using the desktop version of the browser.

Is there a limit on the size of the uploaded presentation?

Yes, the presentation should not exceed 30MB or 100 slides. Because each presentation is converted into a PDF, we recommend saving your presentation as a PDF file yourself. That way, you can ensure that your pages/slides are converted correctly so that no display errors occur.

Is it possible to download the presentations?

Yes, this is possible. However, this function has to be explicitly enabled during the upload. However, any annotations made using the whiteboard tool during the meeting will not be downloaded. To save the annotations as well, a screenshot is necessary.

Will the annotations in the presentation be saved?

No, you will have to make a screenshot of the annotations.

Can I show a video during a meeting?

Playing a video with the screen sharing option is only possible without sound due to BigBlueButton’s security measures to prevent illegal streaming.

If you do not mind making your video publicly available, you can upload it to Vimeo or Youtube and share it using the "share external video" button. This also applies if you upload a video to Vimeo and secure it with a password.

If you prefer to upload the video to the university’s servers, you can use the download platform https://filer.itz.uni-halle.de/. Please note, that this is not a platform specifically designed to play videos. Therefore, you may encounter issues while playing videos.

Alternatively, you can upload the video using the Opencast plugin in your Stud.IP course. For instructions, please refer to our wki.

1. Upload your video on Opencast
2. Click on ‘Media Download’
3. Choose a resolution. Click right on the desired quality and choose ‘copy link’
4. Insert that address in MLUconf in the bar ‘external video URL’

Can I show a video with the screen sharing function?

Yes, but the video will be shared without sound.

I am using Firefox and cannot share specific windows of the Microsoft Edge browser.

UWP apps – apps owned by Windows, such as Cortana, the Edge browser or the calculator tool – run in a sandbox and their windows cannot be shared in Firefox.

If it is necessary to use of these specific apps and you cannot upload screenshots of them as a presentation, we recommend switching to the Chrome or Edge browser for the meeting.