(1) by delivery of a copy of the summons and complaint in accordance with any special arrangement for service between the plaintiff and the foreign state or political subdivision; or
(2) if no special arrangement exists, by delivery of a copy of the summons and complaint in accordance with an applicable international convention on service of judicial documents; or
(3) if service cannot be made under paragraphs (1) or (2), by sending a copy of the summons and complaint and a notice of suit, together with a translation of each into the official language of the foreign state, by any form of mail requiring a signed receipt, to be addressed and dispatched by the clerk of the court to the head of the ministry of foreign affairs of the foreign state concerned, or
(4) if service cannot be made within 30 days under paragraph (3), by sending two copies of the summons and complaint and a notice of suit, together with a translation of each into the official language of the foreign state, by any form of mail requiring a signed receipt, to be addressed and dispatched by the clerk of the court to the Secretary of State in Washington, District of Columbia, to the attention of the Director of Special Consular Services—and the Secretary shall transmit one copy of the papers through diplomatic channels to the foreign state and shall send to the clerk of the court a certified copy of the diplomatic note indicating when the papers were transmitted.
(1) by delivery of a copy of the summons and complaint in accordance with any special arrangement for service between the plaintiff and the agency or instrumentality; or
(2) if no special arrangement exists, by delivery of a copy of the summons and complaint either to an officer, a managing or general agent, or to any other agent authorized by appointment or by law to receive service of process in the United States; or in accordance with an applicable international convention on service of judicial documents; or
(3)
(1) in the case of service under subsection (a)(4), as of the date of transmittal indicated in the certified copy of the diplomatic note; and
(2) in any other case under this section, as of the date of receipt indicated in the certification, signed and returned postal receipt, or other proof of service applicable to the method of service employed.