SRV, which is an abbreviation for Service, is a DNS record, which enables you to employ a domain name for a certain service different from a website. By creating a couple of SRV records, you’ll be able to use the domain address with different companies and direct it to numerous servers simultaneously, each server handling a separate service. You'll be able to specify the port number for the connection to every single machine, so there won't be any interference. You may as well set individual priorities and weight for two records which are employed for the very same service, but point to different servers for redundancy or load balancing. By having an SRV record you can employ your domain address or a subdomain under it for a Voice-Over-IP server, for example, and have the real software running on various machines with different providers. Which one a client of yours is going to use will depend on the priority and weight values which you have set.