1. Erasure codes: next steps
> CCSDS Meeting > Tomaso de Cola
Erasure codes: next steps
Tomaso De Cola
CCSDS Spring Meeting 2014, Noordwijkerhout, 31 March – 3 April 2014

2. Recap from last CCSDS meetings
> CCSDS Meeting > Tomaso de Cola
Recap from last CCSDS meetings
Erasure codes are a powerful means to provide reliability in case of:
DTE optical links (fade events duration ms)
Large propagation delay (Moon+)
RF synchronisation errors because of sun interference
Architecture perspective:
Erasure coding implemented in a layered way, as an independent shim layer (EC shim layer)
Particularly promising as complementary reliability measure implemented below LTP
Implementation status:
LDPC-based erasure codes with fixed code-rate implemented in ION (soon also available for version 3.2.0)

3. The integrated architecture
> CCSDS Meeting > Tomaso de Cola
The integrated architecture

4. 01.04.2014 > CCSDS Meeting > Tomaso de Cola
EC for which services?
EC intrinsically appealing for telemetry and file transfer applications
In terrestrial domain, EC particularly promoted for multimedia (A/V) streaming:
DVB
3GPP
Video streaming also available for space communications (MIA wg):
EC could be powerful to make video streaming more robust ( result from last joint CCSDS DTN-MIA meeting in Fall 2013)
EC could need an ad-hoc code configuration based on A/V codec used by the streaming application

5. 01.04.2014 > CCSDS Meeting > Tomaso de Cola
Some more thoughts…
Future plans to enable video streaming in DTN-based architecture consider the implementation and specification of the Bundle Streaming Service (BSS):
Real-time streaming
The video is played real-time with some erasures, out-of-order stream bundles are stored in the BSS database but not displayed
Later re-play
The entire video can be played later when the missing bundles (available in the BSS database) are eventually received
EC can be used to enable:
Real-time stream with no bundle erasures at the cost of minor delay (encoding, decoding, buffering for jitter issues)
Next steps  to test ION-EC sw with a (video) streaming application

6. Thanks for your attention
> CCSDS Meeting > Tomaso de Cola
Thanks for your attention