Re: [6tisch] The "BEFORE" and "AFTER"

["Pascal Thubert (pthubert)" <[e-mail]>]

This is correct Tengfei, and quite classical.

Headers are like a stack placed in front of the packet. One builds an LOWPAN-IPHC – compressed packet that does not have any RPL artifact in it. Then the RPL artifacts are added as 6LoRH headers. We have not imposed an order yet but it makes sense to place the RPI first if any, then the RH3 if any, then the 6LoRH.

Would you wish that we impose an order to simplify the parsing?

Pascal

From: 6tisch [mailto:[e-mail]] On Behalf Of Tengfei Chang
Sent: mercredi 20 janvier 2016 09:20
To: [e-mail]
Subject: [6tisch] The "BEFORE" and "AFTER"

Dear all,

As recently more discussion in the ML about the format of packet, sometimes we say some header after/before the IPv6 header. I would like to clarify this.

1. For me, I say with the way that mac header is the first header in the packet and then, several Routing Headers are AFTER mac header (no mesh header/fragmenet header in between).  IPHC header is AFTER those Routing Headers.

2. However, with the view of constructing a packet, IPHC is first added into packet, then RHs are placed AFTER IPHC, MAC header is constructed at the end. (I feel pascal is using this way to describe the order of header, right?)

What's the way when we describe something like this?

Thanks
Tengfei