+ mobile (bool): if True then peer is "mobile" ie we assume it may
+ change its apparent IP address and port number without either it
+ or us being aware of the change; so, we remember the last several
+ port/addr pairs we've seen and send packets to all of them
+ (subject to a timeout). We maintain one set of addresses for key
+ setup exchanges, and another for data traffic. Two communicating
+ peers must not each regard the other as mobile, or all the traffic
+ in each direction will be triplicated (strictly, transmitted
+ mobile-peers-max times) and anyway two peers whose public contact
+ address may suddenly change couldn't communicate reliably because
+ their contact addresses might both change at once. [false]
+ mobile-peers-max (integer): Maximum number of peer port/addr pairs we
+ remember and send to. Must be at least 1 and no more than 5. [3]
+ mobile-peer-expiry (integer): For "mobile" peers only, the length
+ of time (in seconds) for which we will keep sending to multiple
+ address/ports from which we have not seen incoming traffic. [120]
+ local-mobile (bool): if True then other peers have been told we are
+ "mobile". This should be True iff the peers' site configurations
+ for us have "mobile True" (and if we find a site configuration for
+ ourselves in the config, we insist on this). The effect is to
+ check that there are no links both ends of which are allegedly
+ mobile (which is not supported, so those links are ignored) and
+ to change some of the tuning parameter defaults. [false]
+
+Links involving mobile peers have some different tuning parameter
+default values, which are generally more aggressive about retrying key
+setup but more relaxed about using old keys. These are noted with
+"mobile:", above, and apply whether the mobile peer is local or
+remote.
+
+** transform-eax
+
+Defines:
+ eax-serpent (closure => transform closure)