Standard Edition server

An internal A record that resolves the fully qualified domain name (FQDN) of the server to its IP address.

Automatic client sign-in

For each supported SIP domain, an SRV record for _sipinternaltls._tcp.<domain> over port 5061 that maps to the FQDN of the Standard Edition server that authenticates and redirects client requests for sign-in. For details, see DNS requirements for automatic client sign-in.

Device Update Web service discovery by unified communications (UC) devices

An internal A record with the name ucupdates-r2.<SIP domain> that resolves to the IP address of the Standard Edition server hosting Device Update Web service. In the situation where a UC device is turned on, but a user has never logged into the device, the A record allows the device to discover the server hosting Device Update Web service and obtain updates. Otherwise, devices obtain the server information though in-band provisioning the first time a user logs in.

A reverse proxy to support HTTP traffic

An external A record that resolves the external web farm FQDN to the external IP address of the reverse proxy. Clients and UC devices use this record to connect to the reverse proxy. For details, see Determine DNS requirements in the Planning documentation.