Which two methods are used by the Expressway for bandwidth control?

The Expressway uses subzones and pipes to control the bandwidth used by endpoints on the network. Subzones are logical groups of endpoints that share the same bandwidth policies and settings. Pipes are logical connections between subzones or zones that limit the total or per-call bandwidth available for calls. The Expressway allows the administrator to configure the bandwidth limits for each subzone and pipe, as well as the behavior when the bandwidth is insufficient or not specified. The other options are not valid methods for bandwidth control on the Expressway. References: Cisco Expressway Administrator Guide (X14.0) - Bandwidth Control, Cisco Expressway Basic Configuration Deployment Guide (X14.0) - Configuring Bandwidth Management