QoS of Media Streams

Media Stream QoS applications measure the quality of media streams, e.g. VoIP or IPTV. Such applications are passive applications that measure quality parameters of a media stream. The application will typically report results and suggest improvements but cannot directly improve the QoS.

Media Stream QoS applications are supported by the Napatech Network Adapters via functionality, such as:

• Time-stamping: Captured frames are time-stamped, enabling the retrieval of exact timing of the frames on the network.
• Packet Classification: The adapter can classify the frames before they are delivered to the host CPU (e.g. recognize the type of frame and find the byte offset to the IP, TCP or UDP payload), whereby the host processing can be accelerated.
• Packet Coloring / Tagging: Captured frames can be colored/tagged depending on frame type. This can accelerate host CPU processing.
• Channel Merging: Enables network frames from several ports to be merged in reception time order and placed in one host buffer. This functionality simplifies merging and retransmit of network frames from several ports to a single port.
• Programmable Filtering: Adapter filters can be set up so that only relevant frames, e.g. VoIP frames, are captured.
• Hash Key Generation: Supports generation of either 2-tuple hash keys (identifying IP-to-IP flows) or 5-tuple hash keys (identifying application-to-application flows). The generated hash keys can be used for Multi-CPU Buffer Splitting but can also be used as part of the frame information to the host, enabling the host CPU to quickly identify a flow.
• Multi-CPU Buffer Splitting: The Napatech Multi-CPU Buffering functionality enables the distribution of the QoS Media Stream Analysis for up to 32 CPU cores.