Why is reverse DNS lookup important?

Related questions

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Tags

1. #particular
2. #application
3. #incoming
4. #address
5. #however
6. #registering
7. #reject
8. #domain
9. #reverse
10. #which
11. #forward
12. #configured
13. #servers
14. #important
15. #server
16. #internet
17. #registrar
18. #mails
19. #point