[1] [CITE@en[RFC 5050 - Bundle Protocol Specification]]
( ([TIME[2010-09-26 05:17:42 +09:00]] 版))
<http://tools.ietf.org/html/rfc5050#section-4.4>

[FIG(quote)[
[FIGCAPTION[
[2] [CITE@en[RFC 5050 - Bundle Protocol Specification]]
([TIME[2015-06-21 13:26:12 +09:00]] 版)
<https://tools.ietf.org/html/rfc5050>
]FIGCAPTION]

> 
>    o  The "dtn" scheme, which is used at minimum in the representation
>       of the null endpoint ID "dtn:none".  The forwarding of a bundle to
>       the null endpoint is never contraindicated, and the minimum
>       reception group for the null endpoint is the empty set.
> 

]FIG]