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 number of SRV records, you will be able to use the domain with different companies and point it to a number of servers at once, each server handling a separate service. You can specify the port number for the connection to each machine, so there won't be any interference. You can also set different priorities and weight for two records that are employed for the same service, but direct to different servers for redundancy or load balancing. With 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 actual software running on a number of machines with different companies. Which one a customer of yours is going to use depends on the priority and weight values which you have set.