MeerKAT, the 64-dish radio telescope built in the arid Karoo region of South Africa, uses Commercial Off The Shelf (COTS) high-speed Ethernet networking equipment to distribute the high volume digitized and processed signal information between computing resources. On MeerKAT, the received analog signals (Horizontal and Vertical polarizations) are digitized at each dish and sent directly to the FX-Correlators data center network in the central processing facility via an extensive underground fiber network. This single data network is also used for data exchange between the correlator components, imager, archive and other instrumentation. MeerKAT welcomes external participation and contribution, and not all instrumentation reflects in-house development. For example, user-supplied equipment is used for pulsar timing, transient searches and even for the search for extraterrestrial life. Here, we describe the data-transfer characteristics of the equipment connected to the network, the network architecture, and the critical role of multicasting in the data distribution. We demonstrate how the flexible nature of the network allows for concurrent processing of the same data streams by different instrumentation and also for multiple, independent observations (subarrays). We conclude with preliminary research into the use of Software-Defined Networking (SDN) for this data network.
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