Fragmentation support in IP

Hi Carsten,

I do understand that IP fragmentation has some serious downsides. Misassociated IP fragments should not be a concern with low data rate use cases though e.g. IoT. But fragment loss is a problem and can result in severely degraded performance especially because of redundant fragment transmissions. I was actually looking for more of a temporary solution to address transmission of payloads in the order of a few kilobytes which would mean 2-4 IP fragments. But it seems like RIOT doesn’t support it.

We don’t want to use CoAP as we are working with ICN (Information Centric Networking) protocols.

And we are working with Attribute-Based Encryption (ABE), a policy based encryption mechanism that may result in significantly increased data after encryption. The increase depends on the complexity of the policy employed.


Hi Adeel,

Hi Oleg,

Yes I looked into it. It did not seem to work right away. Seems like we will have to dig deeper into it. With the time constraints we have, we have a decision to make whether to rely on chunking in CCN-lite or rely on fragmentation in CCN-lite. The fragmentation approach implemented in CCN-lite is the "Begin-End" Hop by Hop Fragmentation scheme (draft-mosko-icnrg-beginendfragment-01) which if I understand correctly does not support recovery of lost fragments. So it seems like a more riskier option in terms of how our prototype will perform compared to using chunking in CCN-lite. With chunking we can retransmit only the lost chunk unlike fragmentation where a lost fragment will mean retransmitting the whole CCN object.