Backwards and forwards compatibility of ETCS baselines

A first baseline compatibility assessment undertaken by the sector (UNIFE/UNISIG and ERTMS Users Group) has checked the compatibility between ETCS baseline 3 MR1 and ETCS baseline 2 (release 230d).

Within the scope of this assessment and provided that its recommendations are taken into account, the ETCS baseline 3 MR1 is backwards compatible with ETCS baseline 2.

A second baseline compatibility assessment has checked that:

• ETCS baseline 3 R2 is fully backward/forward compatible with ETCS baseline 3 MR1
• Both the backward compatibility between ETCS baseline 3 R2 vehicles and ETCS Baseline 2 trackside and the compatibility between ETCS baseline 3 R2 trackside operated with system version X=1 (i.e. ETCS Baseline 3 R2 trackside using only baseline 2 functions) and ETCS baseline 2 vehicles.

The second baseline compatibility assessment also includes the analysis of the compatibility between trackside and onboard both within ETCS baseline 3 MR1 and within ETCS baseline 2, in the light of the problem description of the Change Requests included in ETCS baseline 3 R2.

This second baseline compatibility assessment confirms that the ETCS baseline 3 R2 is fully backwards and forwards compatible with the ETCS baseline 3 MR1, i.e. that ETCS baseline 3 R2 vehicles can run a normal service on ETCS baseline 3 MR1 trackside and ETCS baseline 3 MR1 vehicles can run a normal service on ETCS baseline 3 R2 trackside.