SRV, which is an abbreviation for Service, is a DNS record, which permits you to employ a domain name for a certain service different from an Internet site. By setting up a few SRV records, you can use the domain name with different companies and forward it to many servers at a time, each and every server managing a different service. You'll be able to specify the port number for the connection to every machine, so there won't be any interference. You can also set different priorities and weight for two records which are employed for the same service, but forward 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 real software running on a number of machines with different providers. Which one a customer of yours is going to use is determined by the priority and weight values which you have set.