SRV, which is an abbreviation for Service, is a DNS record, which enables you to use a domain name for a particular service different from a site. By setting up a number of SRV records, you’ll be able to use the domain name with different providers and forward it to several servers at the same time, every single server handling a separate service. You are able to specify the port number for the connection to every single machine, so there will never be any interference. You may as well set different priorities and weight for 2 records that are employed for the same service, but point to different servers for redundancy or load balancing. Using an SRV record you can use your domain name or a subdomain under it for a Voice-Over-IP server, for example, and have the actual software running on various machines with different companies. Which one a client of yours is going to use depends on the priority and weight values you have set.