In a network system where a switching exchange accommodating an ISDN provides TDMoIP packet communication over an IP network, measures for packet loss prevention need to be taken during a period during which a TDM service is packet-transferred over the IP network. The configuration algorithm creates a command procedure comprising a plurality of physical configuration commands to establish a physical configuration for the data storage system. Ring A is an aryl or a heteroaryl optionally further substituted with one or more substituents in addition to R3. The sampling clock generator may generate the reception sampling clock signal based on the frequency difference detection signal and a first reference clock signal. Such means are much smaller in size, but are extremely flexible as to the flow rate and reaction conditions, so that they can be adjusted to suit the reaction, without compromises dictated by attempting to perform other reactions in the same vessel.