SRV, which is an abbreviation for Service, is a DNS record, which enables you to use a domain name for a specific service different from an Internet site. By setting up a couple of SRV records, you can use the domain name with different companies and point it to several servers at a time, each server handling a different service. You are able to specify the port number for the connection to each and every machine, so there won't be any interference. You could also set different priorities and weight for 2 records that are employed for the exact same service, but forward to different servers for redundancy or load balancing. By having an SRV record you can use your domain address or a subdomain under it for a Voice-Over-IP server, for instance, and have the real software running on several machines with different companies. Which one a client of yours is going to use is determined by the priority and weight values that you have set.