{HEAD ~ The source address} of {TAIL ~ the first packet} is set to the first address when the first packet is related to the first service and to the second address when the first packet is related to the second service 
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{ HEAD ~ The source address } of { TAIL ~ the first packet } is set to the first address when the first packet is related to the first service and to the second address when the first packet is related to the second service
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH