M3G stands for “Metadata Management and distribution system for Multiple GNSS networks”. It is a software developed by the Royal Observatory of Belgium (ROB). Registered agencies can upload, validate, and distribute GNSS station metadata via the M3G website. The GNSS station metadata comprise IGS-style site log files, but also information about local networks, DOI, nominal data submissions, etc. M3G has been developed primarily to serve the EPOS, EPN, and EPN densification GNSS networks.
If the submitted metadata is part of the metadata present in the site log, then:
- the updated site log of EPN or EPN densification stations will automatically flow to the EPN Central Bureau. It will take up to 15 minutes for the updated site log to show up at the EPN Central Bureau web and FTP site.
- the updated site log of EPOS stations will automatically flow to the EPOS GNSS Data Gateway.
- the updated site log of IGS stations will have to be submitted to IGS by the Operational Centre (or station manager). M3G will not do this automatically. However, M3G will send a notification to the IGS Central Bureau informing them that the site log was updated.
At present, M3G does not provide this feature, but it will be included in future developments
M3G collects data license of use and embargo period of all stations, but the information is only mandatory for the stations included in the EPOS network. EPOS stations will get the CC BY 4.0 license by default, but this information can be changed by the user. For EPN stations, the embargo period will be automatically set to ‘no embargo period’.
All agencies acting as Operational Centre and maintaining GNSS station metadata of EPN, EPOS, or EPN densification stations have a login account for M3G. Each of these agencies (“Registered Agencies”) has a unique login/password. If the registered agency maintaining the metadata is not the same as the station owner, then the station owner has to formally agree that the registered agency maintains its station metadata in M3G. For EPN or EPN densification stations, one does not need to provide M3G with he agreement. However, for EPOS stations, the data owner has to provide information on who is maintaining the metadata in M3G by submitting the EPOS-GNSS data supplier letter.
Your LOGIN ID is the unique identification code of your agency. You can find it in Agencies under the column "Unique agency ID". If your agency is not in the list, please contact the M3G team. If you do not remember your password, use the button “Reset Password”. All the contacts listed in your agency will receive an email with instructions on how to reset the password.
This might be due to your spam filter or because you are not listed in M3G as one of the contacts in your agency. In the latter case, you need to contact one of your colleagues included in the contact list to ask him/her to reset the password, log in to M3G, and add you to the agency contacts.
You can access to the agency-specific tab (top right in the menu bar) and its submenus:
- "STATION METADATA”: all information related to the stations, e.g. site log, nominal data provision, networks to which the station belongs, data licenses, etc.
- “My agency”: information on your own agency and its contact persons. New contact persons can be added by clicking on
- “Third-party agencies”: information on all agencies (and its list of contacts) involved in the operation of your stations. They can be the on-site agencies, the agencies managing the local networks to which the station contributes, etc…. New third-party agencies can be added by clicking on .
- “Managed networks”: list of all the networks that you have created in M3G. Additional networks can be added by clicking on .
- Login to M3G
- Go to the agency-specific tab (top right in the menu bar) and click on "New station"
- Follow the on-line help (by clicking on the next to the title of the page)
- Update the site log by entering the date of removal of the equipment ("Date Removed") in the most recent (i.e. last) receiver and antenna sections
- Save and submit the site log.
- Send an email to the M3 team to inform us that the station has been decommissioned. We will then switch the status of your station from ACTIVE to FORMER.
- Send an email to the M3G team listing the stations that will be handed over to another agency.
- Put the agency that will take over in copy.
- Station name (9-char ID, e.g. BRUX00BEL)
- Network to which you want to propose the station (EPN, EPN densification, or EPOS network)
- RINEX data types: at present, for EPN and EPOS stations, it is mandatory to provide at least RINEX 2 or RINEX 3 data
For security reasons, starting with M3G v1.0, users cannot remove stations anymore from the list of stations for which they maintain the metadata. If you wish to remove a station, send an email to the M3G team including also the motivation why you wish to remove it e.g. your agency is not maintaining its metadata anymore.
While international and virtual networks can only be setup by the M3G administrator, a registered agency can define local or national networks in M3G, using the “Managed networks” menu in the agency-specific tab (top right in the menu bar), available after login. When defining a new network, the following information is mandatory:
- network abbreviation (must be unique throughout M3G)
- network name
- name of the agency that is responsible to include stations in the network (with a primary and secondary contact). The agency name is selected from a list of agencies that the user has set up already set up in M3G. This can be your own agency or another agency that has been defined as associated third-party agency.
- the DOI associated with the network
After login, go to the agency-specific tab (top right in the menu bar), click on “Update”. You will be redirected to the “Stations overview” table. Click on one of the icons in the column “Export/update information” for the station that you are considering and follow the instructions.
You first have to assign your station to one of the international networks (EPN, EPN densification, or EPOS) that M3G is serving. Indeed, M3G needs to know which metadata validation rules are applicable. To attribute your station to an international network:
- Login to M3G
- Go to the agency-specific tab (top right in the menu bar) available after login
- Click on “Link to networks”
- Once the new page loads, propose the station to at least one international network
In order to comply with GDPR, M3G is linking all the agency/contact information in the site logs with the information entered in "My agency" and "Third-party gencies" in the agency-specific tab (top right in the menu bar). Therefore, check the following information in the site log form:
- Responsible agency: For stations that you set up as third-party stations, you can select one of the third-party agencies. In case you own the station, only your own agency can be selected.
- On-Site Point of Contact Agency: you can select your own agency or one of the third-party agencies.
- the Primary and Secondary Contacts can be selected from the predefined contact list of the selected agency. If the contact is not in the list, click on the last item in the dropdown menu "Add contact to profile" and complete the information of the new contact.
- Login into M3G and go to "My agency" in the agency-specific tab (top right in the menu bar)
- Click on "Modify" below the contact you are interested in
- Change the phone number and clik on "Save"
- Create a new contact by going to "My Agency" (or "Third-party Agencies") in the agency-specific tab (top right in the menu bar) and clicking on in the upper right corner. Insert the contact name whose email you want to change, type the new email address and click on "Save".
- Now you can use the contact with the new email address:
- to update the email address in all the site logs whose contact information is already linked to your agency:
Go to "Link to agencies" in the agency-specific tab (top right in the menu bar), for those stations with under the preview column, change the "Primary/Secondary contact" by selecting the contact with the new email address (the ones you entered in step 1). Click on "Save" to update all site logs. For stations without under the preview column, proceed as below.
- to update the email address a site logs not yet linked to your agency:
Go to "Update" in the agency-specific tab (top right in the menu bar), click on the icon (in the "Export/update information" column) corresponding to the station of interest, and select the contact info with the new email address. Click on "Save" to update the site log. Repeat this for all site logs.
- to update the email address in all the site logs whose contact information is already linked to your agency:
- Delete the contact with the old email address by going again to "My Agency" (or "Third-party Agencies") in the agency-specific tab (top right in the menu bar) and by clicking on "Delete", below the section corresponding to the old contact. If the delete button is not active, it means that the contact with the old email address is still used in the site logs/networks/etc listed in the line "Used in" (above the "Delete" button).
- Edit, validate and submit your site log changes in M3G.
- After the submission, save your site log to your local disk.
- Go to the IGS Site Log Manager and upload the site log that you just saved.
If your agency does not own the station for which you maintain the metadata, that station has to be indicated as a ‘third-party station in M3G. You then need to follow these steps:
- Log in to M3G and select "Third-party agencies" in your agency-specific tab (top right in the menu bar)
- Click on (top right) of the table, enter the information for the agency owning the station, and save
- Go again to your agency-specific tab (top right in the menu bar), and select "Link to agencies"
- Look for the row corresponding to the station and under the column "Third-party station” click on the checkbox
- Indicate the responsible agency (the agency of the station owner that you just entered as an third-party agency), contact info (at the agency of the station owner) and on-site point of contact
- Refer to the FAQ on how to access the site log to update it.
- Go to the specific section and click on in the top right corner.
M3G does not require personal data. It needs however contact information for the agencies that are registered or set up in M3G. This information is entered in M3G by the registered agencies themselves through the “My agency” and “Third-party agencies” submenus, in the agency-specific tab (top right in the menu bar). The agencies can decide to use only a public central contact information (e.g. email aliases pointing to a team). The only mandatory information is the agency name (and abbreviation), address, name of the team (or person) and the corresponding email.
Go to “My agency” in the agency-specific tab (top right in the menu bar) and delete the contact clicking on “Delete”. If the delete button is not active, it means that the contact is still used in a site log, a network, etc. listed in the line "Used in". If the contact is used in a site log, you have to first update the site log by inserting a new contact. Once the contact that you wish to remove is not used anywhere else in M3G, the delete button will become active.
Your personal contact information has been entered in M3G. M3G then asks you if you agree to make this information publicly available without restrictions. M3G will be sending you these kind of emails as long as you do not reply. If you decline the request to make publicly available your personal data, M3G will remove your personal data from all the metadata that are publicly available and replace it with the public central contact of your agency.
- If your agency is registered in M3G, go to the "My agency" in the agency-specific tab (top right in the menu bar), look for your name in the list of contacts, click on "Ask the contact for permission/refusal" button corresponding to your name and you will get a new email request from M3G allowing you to change your decision.
- If your agency is not registered in M3G and, for example, your name has been provided as e.g. a contact person for a GNSS site, ask the appropriate registered agency to send you a new email. They can do this by logging into M3G, going to the “Third-party agencies” menu, and clicking on "Ask the contact for permission/refusal" button corresponding to your name. You will get a new email request from M3G allowing you to change your decision.