Lessons learnt these last 20 years show the incredible success of the "digital companies", that is to say companies that develop themselves the applications that are at the core of their business, and that do it based upon open source. In this sense, "digital companies" are not limited to companies delivering only digital services, but include companies manufacturing physical goods or moving goods or people. Telcos represent an interesting paradox. Core business of a Telco consist obviously in the applications running its network. However, due to history, due to the time when software and hardware were bundled into non-dissociable systems, the sharing of core applications between Telcos has not been done by means of open source, but via a small number of vendors, the Alcatel, Ericsson, Nokia or Huawai. Could this situation evolve in the future ?