[arin-ppml] What is a "host"?

[William Herrin]

On Thu, Sep 9, 2010 at 1:50 PM, Loki Jorgenson <ljorgenson at inetco.com> wrote:
> "Host" tends to be rather over-loaded semantically and in general has
> connotation that ties it to a physical or virtual machine.  It will likely
> be problematic if you don't get your key terms defined, particularly as it
> appears in policy and will need to be interpreted.  "Host" doesn't map well
> to IP addresses except in the simplest case.  And in an increasingly sensor
> network, mobile, and cloud-based world, this won't fit well.


Classically (read: not IPv6), a host is any device that speaks TCP/IP.
Node is used interchangeably while other terms are used to specify
specific types of host, such as a router.


Officially in IPv6: http://www.ietf.org/rfc/rfc4294.txt

      Description of an IPv6 Node
         -  a device that implements IPv6.

      Description of an IPv6 router
         -  a node that forwards IPv6 packets not explicitly addressed
            to itself.

      Description of an IPv6 Host
      -  any node that is not a router.


Obligatory limerick:

A host is a host,
>From coast to coast
And nobody talks to a host that's close,
Unless the host that isn't close
Is busy, hung, or dead.



Regards,
Bill Herrin


-- 
William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
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