Updated by RFC 1101, RFC 1183, RFC 1348, RFC 8490, RFC 8482, RFC 8767, RFC 2308, RFC 2137, RFC 2181, RFC 1982, RFC 2136, RFC 1996, RFC 1995, RFC 1876, RFC 2065, RFC 4034, RFC 4035, RFC 4343, RFC 5966, RFC 6604, RFC 2535, RFC 2673, RFC 2845, RFC 5936, RFC 3425, RFC 3658, RFC 4033, RFC 7766, RFC 9619 Network Working Group P. Mockapetris Request for Comments: 1035 ISI November 1987 Obsoletes: RFCs 88