SRV, which is an abbreviation for Service, is a DNS record, which allows you to use a domain name for a particular service different from an Internet site. By creating a few SRV records, you can use the domain with different companies and forward it to several servers at the same time, each and every server managing a different service. You can specify the port number for the connection to each machine, so there will not be any interference. You could also set individual priorities and weight for two records that are employed for the exact same service, but direct to different servers for redundancy or load balancing. Using an SRV record you can employ your domain name or a subdomain under it for a Voice-Over-IP server, for instance, and have the actual software running on a number of machines with different providers. Which one a client of yours will use depends on the priority and weight values which you have set.