An example of R190(3)(f): A foreign national in possession of a TRV valid for 1 year, who is subsequently issued a four-year SP at a POE, may leave and return to Canada after the expiry of the TRV as long as they have only visited the U.S. or St. Pierre and Miquelon and the SP is still valid.
Dynamic DNS (DDNS or DynDNS) is a method of automatically updating a name server in the Domain Name System (DNS), often in Not Real Time, with the active DDNS configuration of its configured hostnames, addresses or other information.he term is used to describe two different concepts. The first is dynamic DNS updating which refers to systems that are used to update traditional DNS records without manual editing. These mechanisms are explained in RFC 2136, and use the TSIG mechanism to provide security.
In computer networking, reverse DNS lookup or reverse DNS resolution (rDNS) is the determination of a domain name that is associated with a given IP address using the Domain Name System (DNS) of the Internet. Computer networks use the Domain Name System to determine the IP address associated with a domain name. This process is also known as forward DNS resolution. Reverse DNS lookup is the inverse process, the resolution of an IP address to its designated domain name. The reverse DNS database of the Internet is rooted in the Address and Routing Parameter Area (. ) top-level domain of the Internet. IPv4 uses the. domain and the. domain (previously. ) is delegated for IPv6. The process of reverse resolving an IP address uses the pointer DNS record type (PTR record).