Re: [Teas] [netmod] Typedefs for bandwidth

[Juergen Schoenwaelder <[e-mail]>]

I assume it is best to settle this in teas. Form a programmatic point
of view, you likely want to have a single unit. Even if you go for bps
(bits per second), a uint64 still allows you to express quite big data
rates (I think 16777216 terra bits per second but please check
yourself). From a human point of view, having a notation that supports
different units may be desirable. But if you have multiple
representations, this surely increases implementation cost and it gets
you into answer questions whether there should be a canonical format
or a way to decide which unit is selected. Writing constraints in when
or must statements will also become much more fun.

Whether you really need the range of a floating point number, I can't
tell. Perhaps check what the realistic smallest and biggest bandwidth
is that you need to represent. Generally, floating point numbers seem
to be a no-brainer for management application writers but I have been
told that they are less frequently found in line cards or OS kernels.

/js

On Fri, May 14, 2021 at 10:08:00AM +0000, Italo Busi wrote:
> Reshad, Juergen,
> 
> Actually, there is some on-going discussion within TEAS because some packet technology-specific YANG modules are not using the bandwidth-ieee-float32 but prefers using some uint type:
> 
> https://github.com/tsaad-dev/te/issues/116
> 
> The ietf-te-packet-types already defines bandwidth-kbps, bandwidth-mbps and bandwidth-gbps but during the discussion of this open issue it was pointed out that it would be desirable to specify both the bandwidth and the units (Kbps/Mbps/Gbps)
> 
> Italo
> 
> > -----Original Message-----
> > From: Juergen Schoenwaelder [mailto:[e-mail]]
> > Sent: giovedì 13 maggio 2021 19:25
> > To: Reshad Rahman <reshad=[e-mail]>
> > Cc: '[e-mail]' <[e-mail]>
> > Subject: Re: [netmod] Typedefs for bandwidth
> > 
> > On Thu, May 13, 2021 at 11:57:26AM -0400, Reshad Rahman wrote:
> > > Hi,
> > >
> > >
> > >
> > > Has there been any discussions wrt adding new  bandwidth types e.g. the
> > bandwidth-xxx types in draft-ietf-teas-yang-te-types? I see RFC8294 has
> > bandwidth-ieee-float32 but it doesn’t have units (Kbps/Mbps/Gbps).
> > >
> > 
> > The description of bandwidth-ieee-float32 says:
> > 
> >           The units are octets per second.
> > 
> > Note that draft-ietf-teas-yang-te-types has been published as RFC 8776 in June
> > 2020, it should be safe to use these definitions.
> > 
> > /js
> > 
> > --
> > Juergen Schoenwaelder           Jacobs University Bremen gGmbH
> > Phone: [phone]         Campus Ring 1 | 28759 Bremen | Germany
> > Fax:   [phone]         <https://www.jacobs-university.de/>
> > 
> 

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: [phone]         Campus Ring 1 | 28759 Bremen | Germany
Fax:   [phone]         <https://www.jacobs-university.de/>