Packet Tags

[Lina]

Hi all,

I'm wondering if it is possible to add two different tags (SNR tags) to a packet??

Thanks in advance.

Lina

[Tommaso Pecorella]

Hi,

you can add two DIFFERENT tags to a packet. You can not add the same tag twice.

Cheers,

T.

[Lina]

Hi Tommaso,

That's exactly what I need to do, adding two different tags to a packet.

So far I only have the SNR tag as follow:

/ **********  SNR TAG  *********** //
      SnrTag tag;
      tag.Set(signalDbm - noiseDbm);
      if (! packet->PeekPacketTag (tag))
        {
          packet->AddPacketTag (tag);
          NS_LOG_DEBUG("Add SNR Tag with value :" << tag.Get());
        }

 // *********  SNR TAG  *********** //

Reference: https://groups.google.com/forum/#!searchin/ns-3-users/snr$20tag/ns-3-users/eLAgrrd1aw4/MAhJEYUj60oJ

and I need to add another tag for the received signal. how can I do that? 

Thanks.

Lina

[Konstantinos]

You could simply update the SnrTag code to hold two values (snr and received signal).

That would be easier to implement than a new tag. 

Regards,

K.

[Tommaso Pecorella]

That's called RSSI.

About extending the actual tag vs making a new one, I have different opinions. Extending the actual SnrTag is easier. However it is also a bit more painful when you try to upgrade ns-3. Moreover it can lead to hard to find bugs (e.g., you forgot to set the RSSI value). A missing tag is easy to spot, a default value isn't.

Anyway, defining a new tag is a matter of copy-paste end renaming. So the two options are not that different.

Cheers,

T.

[Lina]

Thanks all for your help.

I've created a new tag and its working.