IALA is establishing the S-200 domain, in consultation with IHO. This domain uses the range S-201 to S-299 for product specifications compliant with the IHO S-100 standard, covering fields within the IALA remit, including Aids to Navigation (AtoN), Vessel Traffic Services (VTS), positioning systems and communication systems.

IALA has worked closely with IHO and other bodies to develop S-200 product specifications within its areas of responsibility, in particular AtoNs and VTS. A supervisory structure (IALA Guideline 1087) has been established within IALA to manage its domain, which, with the approval of IHO, has been allocated the numbering series S-201 to S-299.

The IALA eNAV Committee oversees this work through the Harmonization Working Group (WG1). IALA Guideline 1106 sets out the process for preparing S-200 product specifications and has been revised and updated as experience has been gained. 2 product specifications (S-201 and S-240) are ready for review and approval and several others are under development.

PS No.	Title	Developer	Field Manager	Status	Edition
S-201	Aids to Navigation Information	KRISO/CCG for ARM WG2	Sewoong OH osw@kriso.re.kr	Draft Completed for review	Draft 0.0.7 for review
S-210	Inter VTS Exchange Format	VTS WG2	R Hoogendoorn	Pending changes to S-100 to allow for data streaming applications
S-211	Port Call Messages	IPCDMC	M Bergmann	Draft Completed for review
S-230	Application Specific Messages	ENAV WG1	P Hooijmans	Planned
S-240	DGNSS Station Almanac	KRISO for ENG	Cho Yonghun	Completed for review	Draft 0.0.2
S-245	eLoran ASF Data	KRISO for ENG	P Williams	Under development
S-246	eLoran Station Almanac	KRISO for ENG	P Williams	Under development
S-247	Differential eLoran Reference Station Almanac	KRISO for ENG	P Williams	Under development