SRV, which is an abbreviation for Service, is a DNS record, which enables you to employ a domain name for a particular service different from a site. By creating a number of SRV records, you’re able to use the domain name with different companies and forward it to several servers simultaneously, every single server handling a separate service. You could specify the port number for the connection to each and every machine, so there will never be any interference. You could also set different priorities and weight for two records that are employed for the exact same service, but direct to different servers for redundancy or load balancing. By having 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 real software running on various machines with different companies. Which one a client of yours is going to use depends on the priority and weight values that you've set.