DNS
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1.1. Slow propagation of new and changed data in a DNS zone can be
due to a zone's relatively long refresh times. Longer refresh ...
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1.2. The DNS NOTIFY transaction allows master servers to inform slave
servers when the zone has changed -- an interrupt as opposed to poll
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3.2. NOTIFY uses the DNS Message Format, although it uses only a
subset of the available fields. Fields not otherwise described
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... NOTIFY as a means of synchronizing an SOA query and UDP/DNS
spoofing as a means of forcing a zone transfer. ...