Where is latency measured?

Reuters Latency Monitor (RLM) provides RMDS clients with an end-to-end solution for real-time monitoring of system latency. The definition of endpoints is configurable, but for market data streams it is generally defined as from the exchange to the customer or from the Reuters Data Feed (RDF) to the consuming application.

For customer premises solutions, NinjaBox-LM connects to the span ports of enterprise switches or routers, or network taps and measures transit point delays between key components of the RMDS. This is achieved by measuring the delay experienced by a market data message moving between observer points. The message is tracked using a combination of specific identifiers such as ticker symbol and sequence number. The delay itself is calculated by Trading Metrics analysis software, based on the accurate time stamping applied to messages by the NinjaBox-LM at each observation point.

While this provides an accurate measurement of delays inside the customer's network, users are also interested in the delay incurred between the exchange itself and the customer location. A timestamp is typically inserted into market messages as they leave an exchange and can be extracted, with delay measured, upon arrival at the customer's premises.