To calculate a utilization percentage, two values are necessary: the measured usage (numerator) and the total capacity (denominator). Riverbed AppResponse measures the actual traffic volume for a defined Host Group from packet data. However, it has no inherent knowledge of the total bandwidth capacity of the physical or logical link that the Host Group's traffic traverses. Therefore, the administrator must manually configure the Inbound and Outbound bandwidth values within the Host Group's settings. AppResponse then uses these user-defined capacity values as the denominator to calculate and report the Link Utilization Percentage metric for that specific group.

A. SNMP Polling is enabled: SNMP is used to poll metrics from network infrastructure devices (e.g., routers, switches), not to define the capacity for a logical Host Group within AppResponse.

C. WMI polling is enabled: WMI is used to collect performance metrics directly from Windows servers (e.g., CPU, memory), which is unrelated to the network link's bandwidth capacity.

D. Flow collection is enabled: While flow data provides information about traffic volume, it does not contain the total bandwidth capacity of the link, which is essential for calculating a utilization percentage.

1. Riverbed AppResponse 11.13 User's Guide, Chapter 4: "Configuring AppResponse," Section: "Defining Host Groups," Page 101.

The guide details the configuration options for Host Groups. For the "Inbound Link Bandwidth" and "Outbound Link Bandwidth" settings, the description explicitly states: "Used to calculate Link Utilization % for this host group." This directly confirms that specifying the bandwidth is the prerequisite for this calculation.