[ns] Bandwidth of wireless channel

[Vinod]

Dear Daniel,

Thanx for your reply.

Actually, my problem involves calculating the effective bandwidth of a 
wireless node (more specifically in a MANET). I guess the bandwidth_ 
variable of MAC or Phy layers dont give this value.

I am using the default parameters given in the AODV implementation.

To put it more clearly, suppose node 'S' wants to send a pkt to 'R'.
This pkt can either be forwarded through 'A' or 'B' (A & B are one hop 
neighbors of S) depending on the bandwidth. So, I am planning to calculate 
the effective bandwidths of A and B and choose the node based on it.

Can you (or anyone) suggest a way for this. I would be thankful

Vinod
----------------------
Vinod Kone,
Btech,Computer Science,
VIII sem,
Room 177,Kapili,
IIT Guwahati.

On Wed, 12 Apr 2006, Daniel Mahrenholz wrote:

> Vinod schrieb:
>> im working in qos routing in mobile adhoc networks.
>> 
>> can anyone tell me why the "default" value of bandwidth is 0 in link layer 
>> of type "LL" (wireless routing simulation). Does that mean its not used or 
>> something else? I can see that the "delay" value is set to 25us by 
>> default.
>> 
>> Also, can anyone tell me whether i can have "cost" param attached to 
>> wireless links as we can do in wired?
>> 
> The short answer - there is nothing like a "wireless link". Wireless 
> communication uses a broadcast medium. Links are only logically defined by 
> your MAC layer or routing protocol. Additionally you do not have something 
> like a universal "bandwidth of the wireless channel". This depends on your 
> technology, modulation schemes etc. So you have to setup this value depending 
> on your model technology (e.g. 2 Mbit/s for a WLAN using BPSK modulation).
>
> Daniel.
>