Re: [ipwave] Hidden terminal problem

[Abdussalam Baryun <[e-mail]>]

On Tue, Apr 16, 2019 at 5:50 PM Charlie Perkins <
[e-mail]> wrote:

> Hello Alex,
>
> Consider the following three nodes with radio links as shown:
>
> A----------B----------C
>
> Suppose that A and B are at 80% of their signal range, and also that B
> and C are at 80% of their signal range.
>
> So A and C are not in range.  So A is 'hidden' from C, and C is 'hidden'
> from A.
>
> That's the hidden terminal problem.  It's not specific to OCB or WiFi,
> and it is not a hypothetical problem.  It's just physics. It's not at
> all difficult to understand, but it is very important to understand.
>

Yes but it has been reduced its effects of collisions by CSMA/CA, and by
using control frames,


>
> One question below...
>
> On 4/16/2019 3:18 AM, Alexandre Petrescu wrote:
> >
> > ...
>
> >
> > I do not know how the hidden terminal problem works.  I feel like if I
> > start looking into it I will grow additional white hairs.  I feel like I
> > better avoid  it.
>

usually it is the IEEE problem to solve not this WG problem. I believe they
solved it.


> >
> > I think other people have some experience with the hidden terminal
> > problem in non-OCB WiFi and 802.15.4.  I am listening to them.
>

usually MIMO technology has change many issues, but 802.15.4 is big
different MAC than 802.11,

> >
> > I think nobody has any experience with the hidden terminal problem in
> > OCB settings.  I have some doubts, but still I think it is almost nobody.
> >
> >
> I find this very surprising!  What do others think?
>

I think usually this hidden terminal is old problem now IEEE802.11 has been
updated, solving many old problems including that. It is called now hidden
station in IEEE802.11 new docs. In old sunets and terminals they have no
intelligence but now the stations are smart especially when it is a Car not
a sensor, because a Car has big storage and power capabilities that can
help to increase intelligence and decision making.

AB


> Regards,
> Charlie P.
>
> _______________________________________________
> its mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/its
>