proposal 133

i2p2www/spec/proposals/133-introducer-expiration.rst

+=====================
+Introducer Expiration
+=====================
+.. meta::
+    :author: zzz
+    :created: 2017-02-05
+    :thread: http://zzz.i2p/topics/2230
+    :lastupdated: 2017-02-05
+    :status: Open
+
+.. contents::
+
+
+Overview
+========
+
+Introducers expire after a certain time, but that info isn't published in the Router Info.
+Routers must currently use heuristics to estimate when an introducer is no longer valid.
+
+
+Motivation
+==========
+
+Improve success rate for introductions.
+
+
+Design
+======
+
+Include new parameters in a SSU Router Address containing introducers.
+
+
+Specification
+=============
+
+In a SSU Router Address containing introducers, the publisher may optionally include expiration times for each introducer.
+The expiration is specified as iexpX=nnnnnnnnnn where X is the introducer number (0-2)
+and nnnnnnnnnn is the time in seconds (not ms) since the epoch.
+
+Each expiration must be greater than the publish date of the Router Info,
+and less than 6 hours after the publish date of the Router Info.
+
+Publishing routers and introducers should attempt to keep the introducer valid until expiration,
+however there is no way for them to guarantee this.
+
+Routers should not use a published introducer after its expiration.
+
+Example: iexp0=1486309470
+
+
+Migration
+=========
+
+No issues. Implementation is optional.
+Backwards compatibility is assured, as older routers will ignore unknown parameters.
+
+
+
+See Also
+========
+
+Trac ticket 1352