Route
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... identify an intermediate hop towards that resource (in which case,
the URI is found in the Route header). The procedures defined here
in no way affect this URI ...
... requirement that it be delivered
to the same server that received the original request (indeed, if
that server did not record-route, it will not get the ACK).
...
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then should the element fail, there is no way to route the request or
response through a backup.
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