Re: [v6ops] WGLC: draft-ietf-v6ops-unique-ipv6-prefix-per-host-02 - multiple prefixes per device

[Fred Baker <[e-mail]>]

On Mar 16, 2017, at 10:24 AM, [e-mail] wrote:
> 
> A little flippant perhaps, but can you give an example of a node that isn't a router anymore?
> I think the statement "All hosts are routers" is almost true.
> 
> Certainly my phones, laptops, lightbulbs are all routers.

</hat>

I'd like to understand your meaning, if you don't mind.

A router, per RFC 2460, is a system that receives a message, does no processing on its content, but repeats it to another system. A host is one that receives messages and processes their application layer content.

I think it's fair to say that an iPhone etc has more than one interface; WiFi and LTE, perhaps. A laptop often has several interfaces such as physical and wireless Ethernet, USB, Bluetooth, and other things. Having multiple interfaces, however, does not qualify it as a router; what qualifies it as a router is when it receives a message and repeats it, usually on another interface.

Yes, an iPhone acting as a hot spot can route between its WiFi and LTE ports. If it is not configured as a hot spot, however, it generally uses its many interfaces as ways to receive messages, pass them to applications, and respond to them. Absent a specific (and unusual) configuration, an iPhone therefore is a host, not a router.

Are you and I using the words in the same way? I get the feeling that you see multiple interfaces and infer "router".