47Provisioning Client User GuideFor example, using Nortel, you can have nortel.com as the root domain, withsubdomains of Richardson and Ottawa. Additional subdomains can exist undereach of these subdomains, as shown in the following figure.Foreign domainsWhen adding a domain, you must determine whether the domain is a foreigndomain. A foreign domain uses foreign routes, while a local domain uses SIProuting or telephony routes. You can add foreign domains at any time.A domain that is not local is considered foreign. Usually, a foreign domain isresolved through DNS and does not need to be provisioned. However, becausesome deployment scenarios cannot involve a DNS server, you can datafill routesfor a foreign domain.
