摘 要: | The ALICE detector at LHC( CERN),will record raw data at a rate of 1.2 Gigabytes per second.Trying to analyse all this data at CRN will not be feasible.As originally proposed by the MONARC project,dta collected at CERN will be transferred to remote centres to use their computing infrastructure,The remote centres will reconstruct and analyse the events.and make available the results.Therefore high-rate data transfer between computing centres(Tiers)will become of paramount importance.This paper will present several tests that have been made between CERN and remote centres in Padova(Italy),Torino(Italy),Catania(Italy),Lyon(France),Ohio(United States),Warsaw(Poland)and Calcutta( India),These tests consisted,in a first stage,of sending raw data from CERN to the remote centres and back,using a ftp method that allows connections of several streams at the same time.Thanks to these multiple streams,it is possilble to increase the rate at which the data is transferred.While several “multiple stream ftp solutions“ already exist,our method is based on a parallel socket implementation which allows,besides files,also objects(or any large message)to be send in parallel.A prototype will be presented able to manage different transfers.This is the first step of a system to be implemented that will be able to take care of the connections with the remote centres to exchange data and monitor the status of the transfer.
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