Most XSEDE Service Providers (SPs) offer remote login services that provide a command-line (aka, "shell") interface on one or more dedicated login nodes. The command-line interface allows users to execute commands and scripts on the login nodes. These commands include job submission commands that add jobs to the resource's compute queue(s). The commands can also provide access to the mass storage system(s) provided by the SP. Remote login services are restricted to use by users with allocations on the resource. User authentication (login) is via a username and password assigned by the SP or a username and password assigned by XSEDE, and also usually requires two-factor authentication (TFA) with a hardware or software one-time code generator.