Explanation
According to the Default policy settings document for Citrix Virtual Apps and Desktops 7 2308, the default compression policies are stored in the site database and are applied to the VDAs when they register with the broker or when a user connects to them. To use the default compression policies, a Citrix administrator needs to bind them to the virtual server that handles the ICA traffic. This can be done using the Web Studio console or the Local Group Policy Editor. The other options are not related to the default compression policies.

Explanation
Citrix Gateway can be hosted in Citrix Cloud or in a customer-controlled resource location. It provides secure remote access to Citrix Virtual Apps and Desktops service deployments.

Explanation
According to the Citrix documentation1, nslog is a log that records detailed information such as statistics, metrics and debug information on the Citrix ADC in a proprietary binary format. Nstrace is a log that captures network traffic on the Citrix ADC in a standard pcap format. Syslog is a log that records system events and messages on the Citrix ADC in a standard text format. Nsconfig is a file that contains the configuration settings of the Citrix ADC.