SRV, which is an abbreviation for Service, is a DNS record, which permits you to use a domain for a certain service different from an Internet site. By setting up a few SRV records, you’re able to use the domain with different providers and direct it to several servers at a time, every single server managing a separate service. You could specify the port number for the connection to each machine, so there will not be any interference. You could also set different priorities and weight for 2 records which 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 or a subdomain under it for a Voice-Over-IP server, for example, and have the actual software running on a number of machines with different companies. Which one a client of yours will use depends on the priority and weight values you have set.