Re: [netmod] 6991bis: address-with-prefix-length

Kristian Larsson <kristian@spritelink.net> Thu, 18 April 2019 21:11 UTC

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From: Kristian Larsson <kristian@spritelink.net>
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Subject: Re: [netmod] 6991bis: address-with-prefix-length
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On 2019-04-18 18:02, Juergen Schoenwaelder wrote:
> On Thu, Apr 18, 2019 at 03:14:20PM +0200, Per Hedeland wrote:
> 
>> Agreed - except the not entirely minor nit that the thing after the
>> "/" is not a prefix but a *prefix-length*. Another way of putting it
>> is that the IP address is a property of an interface, while the
>> prefix-length or subnet mask is a property of the network that an
>> interface is connected to.
> 
> The property relevant for the network is the _prefix_, not the
> prefix-length. 

Agreed.


> The prefix-length 12 does not tell the system the
> network prefix that is valid on the link, the prefix tells it. In
> other words, you have a single value that gives you an address and a
> prefix, hence ip-address-and-prefix. The question is whether we name
> it according to the pieces that go into the combined value or whether
> we name it according to the meaning of the combined value. What goes
> in is "address + prefix length" and the meaning is "address + prefix".

Very good analysis on why we have different opinions for the name :)

I can tell someone "enter the address and prefix-length" and they will 
understand what I mean. I don't think it is clear what to enter if 
someone says "enter the address and prefix".. this is why I think 
ip*-address-and-prefix-length is the more natural name :)

Kind regards,
    Kristian.