EMDI Overview
Enhanced media delivery index (EMDI) allows E2E measurement of the multicast video service packets specified on each network node on an IP network so that performance indicators including the packet loss rate, packet out-of-order rate, and jitter can be obtained. eMDI has the advantages of easy deployment, full NE coverage, and high statistical precision.
Background
Multicast video services, including IPTV, are gradually deployed on carrier networks and have become a major opportunity to improve profitability for carriers. Quality monitoring of video services is of vital importance. Packet loss rate, packet out-of-order rate, and jitter are three major factors that may affect video quality. Even the packet loss rate and packet out-of-order rate of less than 0.01% may cause terminals to experience erratic display or mosaic. Jitter may also lead to black screen. These problems severely affect the service quality of experience (QoE) as well as the profitability and brand awareness of carriers. A video quality monitoring and fault locating solution is in need so that carriers can monitor and maintain service quality in real time and quickly demarcate faults and clarify responsibilities.
The eMDI detection solution is a quality monitoring and fault locating solution designed for multicast video services such as IPTV. This solution supports real-time detection of quality indicators (such as packet loss rate, packet out-of-order rate, and jitter) of real service packets, featuring high statistical precision and reliable data support. In addition, this solution can be deployed on all network nodes from edge devices to core devices. The detection results on multiple nodes help to rapidly locate the faulty network segment.
Detection Principles
The eMDI detection solution is a distributed board detection solution. During solution deployment, the channels to be detected are added to a channel group, the eMDI-capable boards are added to a board group, and the channel group is bound to the board group. With detection on the board NP, the video streams of specified channels can be detected in distributed mode.
This solution supports detection only of UDP-based Real-Time Transport Report (RTP) video streams. The NP of the board to be detected performs validity check and RTP check on the IP header, UDP header, and RTP header of RTP packets and calculates the packet loss rate and packet disorder rate based on the sequence number in the RTP header. Then, the NP calculates jitter based on the timestamp in the RTP header, achieving real-time monitoring of video quality.
- The NMS delivers eMDI monitoring instructions to a device.
- The device monitors eMDI indicators in real time.
- The device periodically reports the monitored eMDI indicators and alarms to the NMS.
- The NMS displays eMDI indicators in GUI mode and supports analysis on fault demarcation and locating.
Indicator Collection
eMDI can obtain monitoring data from a device on a regular basis and periodically send the data to the NMS in various modes such as telemetry. After analysis on the NMS, the monitoring data can be displayed in various forms, such as a trend chart.
eMDI also supports reporting of alarms to the NMS. The alarm thresholds and the number of alarm suppressions can be configured as required.
Indicators
The detection indicators supported by eMDI include the packet loss rate (RTP-LR), packet out-of-order rate (RTP-SER), and jitter. The packet loss rate and packet out-of-order rate are calculated based on the sequence number in an RTP packet header. The jitter is calculated based on the timestamp in an RTP packet header. For details, see eMDI Detection Indicators.