Check if channel exist before sending network map

[mlsmaycon]

Describe your changes

Check for connection channel before calculating and sending the network map

Issue ticket number and link

Checklist

• [ ] Is it a bug fix
• [ ] Is a typo/documentation fix
• [x] Is a feature enhancement
• [ ] It is a refactor
• [ ] Created tests that fail without the change (if possible)
• [ ] Extended the README / documentation, if necessary