SRV, which is an abbreviation for Service, is a DNS record, which permits you to employ a domain name for a specific service different from a website. By creating a number of SRV records, you will be able to use the domain address with different providers and direct it to a number of servers simultaneously, every single server handling a separate service. You could specify the port number for the connection to every single machine, so there won't be any interference. You can even set individual priorities and weight for two records that are used for the very same service, but direct to different servers for redundancy or load balancing. Using an SRV record you can employ your domain or a subdomain under it for a Voice-Over-IP server, for example, and have the specific software running on various machines with different providers. Which one a client of yours will use depends on the priority and weight values that you have set.