Refer to the exhibit. A company recently deployed Cisco Jabber. Users log in to Jabber by using their email address in a domain named company.com. The users report that they cannot register their…

The `company.com` domain must be resolvable by both Expressway-C (internally) and Expressway-E (for external resolution via public DNS) to facilitate proper client discovery and routing.

When Jabber clients connect from outside the corporate network (e.g., from home without VPN), they rely on public DNS to discover the Expressway-E for various services, including telephony. A missing SRV (Service Record) for the `company.com` domain prevents Jabber from finding the necessary service entry points, thus failing registration without a VPN.

While an incorrect TTL value can cause intermittent issues, it's less likely to completely prevent service registration for all remote users than a missing record. A short TTL would cause frequent lookups, not a failure to find the service.

The number of responses for a domain is generally not the direct cause of Jabber telephony service registration failure. Multiple responses are common for load balancing or redundancy.