SRV, which is an abbreviation for Service, is a DNS record, which allows you to employ a domain for a particular service different from a site. By setting up a few SRV records, you’ll be able to use the domain with different companies and point it to several servers at once, each and every server managing a different service. You can specify the port number for the connection to every machine, so there will never be any interference. You can even set individual priorities and weight for two records which are employed for the exact 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 instance, and have the specific software running on various machines with different companies. Which one a client of yours will use is determined by the priority and weight values you have set.