Dissemination data are transmitted to Member States using TCP/IP protocol. Telecommunications network and line speeds are illustrated on http://rmdcn.ecmwf.int/. Each Member State is assigned topically one normal and one temporary destination designator, and any reasonable number of dissemination streams. For each dissemination stream, a set of dissemination requirements is maintained (either by ECMWF or by the Member State - see Section 13 for details). One file containing all requested products for a dissemination stream is transmitted per a verifying time for each of the available data streams.

For GRIB data, octets between the end of one message and the beginning of the next should be ignored. Messages are separated by padding (optionally could be disabled) to multiples of 120 octets to ensure word alignment at the beginning of each message.

The following dissemination filename convention is used for the transmission of ECMWF dissemination products:

ccSMMDDHHIImmddhhiiE where:

cc	is	Dissemination stream name;
S	is	data stream indicator:
		`D'	Main deterministic model products,
		`A'	Weather Parameter products,
		`P'	Global Wave Model products,
		`M'	Mediterranean (European) Wave Model products,
		`E'	EPS products (control and perturbed forecast);
		`B'	EPS Weather Parameter products,
		`Y'	EPS derived products (other then control and perturbed forecast)
		`W'	Wave EPS products;
		`U'	Wave EPS derived products (other then control and perturbed forecast);
		`Q'	Boundary Condition WAVE Project products;
		`S'	Boundary Condition Project products;
		`X'	Multi-Analysis Ensemble Data products.
		`L'	Seasonal Forecasting System products
		`C'	Tropical Cyclone deterministic trajectory forecast products
		`T'	Tropical Cyclone EPS trajectory forecast products
		`F'	Monthly Forecast real time atmospheric data
		`H'	Monthly Forecast hindcast atmospheric data
		`V'	Monthly Forecast real time wave data
		`Z'	Monthly Forecast hindcast wave data

MMDDHHII	is	is month, day, hour and minute on which the products are based;

mmddhhii	is	is month, day, hour and minute on which the products are valid at; ddhhii is set to "______" for Seasonal Forecasting System products; (ii is set to 01 for deterministic forecast time step zero, type=fc,step=0);

E	is	Experiment Version Number' (as EXPVER in MARS):
		`1'	All current operational products.

Should any test suite data be made available in dissemination in the future, E will represent the test suite EXPVER number which might be more than one digit.

16-04-2012