Re: how to only enable some node to use multiPath?

["Guo, Liang" <guol@cs.bu.edu>]

Thanks for fast responding.

On Tue, 9 Nov 1999, Lloyd Wood wrote:

> On Tue, 9 Nov 1999, Guo, Liang wrote:
> 
> > I want to only enable some nodes in the network to be able to
> > use multiPath (while others are not), according to NS document,
> > I should do something like:
> > 
> > set n1 [$ns Node]
> > $n1 set multiPath_ 1
> > 
> > however, these doesn't work, seems that "multiPath_" setting
> > can only be applied to all or none. Is that true? 
> 
> Shouldn't be the case; the documentation on that hasn't changed for
> well over a year, and the stuff in ~ns/tcl/lib/ns-node.tcl looks okay. 
> Try:
> 
> Node set multiPath_ 1
> set n1 [$ns Node]   ;# this node should be multipath-aware
> Node set multiPath_ 0
> set n2 [$ns Node]   ;# this node shouldn't be
> 
> etc. as a workaround, since that ought to work even in the new node
> API, whereas I'm no longer at all sure about the other method.
>

Nope, after doing this, all node will disable multiPath_, i.e.,
variable setting statement will override previous settings, and
it will affect all other objects. (Is this a fault of OTcl 
intepreter?)

 
> (you do need DV routing to boot.  multipath as an option with god-mode
>  perfect routing would be nice.)
> 

Yes, I did turn DV on, that's the only guy who allows multipath routing
(in standard package).

> 
> > If so, how to modify the code to enable partial "multiPath_" setting?
> 
> Should be working without modification already; examine the instprocs
> in ~ns/tcl/lib/ns-node.tcl.
> 
> Actually, this I-only-want-it-partially problem applies to a large
> number of bound variables use for global settings, where you want
> global default values, but settable per-node or per-link values - so
> the node will inherit the global value, but it can be explicitly
> overriden on a per-node basis. (okay, multiPath is handled in Tcl and
> only looks_ like a bound variable.)
> 
> This is something I was suggesting to Tom for the large number of
> bound global variables settable in OTcl that were introduced by the
> satellite code, because you'd e.g. want to set elevation_mask_ on a
> per-terminal basis, and not globally for all terminals via:
> 
> HandoffManager/Term set elevation_mask_ 40
> 

Well, maybe I should try this. (Although this is the last option I would
like to use).

> (or the sort of thing you find in  tcl/ex/wireless-demo-csci694.tcl)
> 


Thanks again, 


Guo, Liang.