Can a user associate and use his own DNS with ELB instead of the DNS provided by AWS ELB?
Yes, by creating a CNAME with the existing domain name provider
Yes, by configuring DNS in the AWS Console
Yes, only through Route 53 by mapping ELB and DNS
The AWS ELB allows mapping a custom domain name with ELB. The user can map ELB with DNS in two ways:
1) By creating CNAME with the existing domain name service provide
2) By creating a record with Route 53