in the book internet architectures by Sam Halabi, pg 228, this is the diagram link
it mentions
RTC receives the 0/0 via EBGP (from its own provider), IBGP, and OSPF. It ignores
the OSPF default, as mentioned earlier.
RTC prefers the 0/0 coming from RTD via IBGP because of the higher local
preference.
i understand that when you compare iBGP to eBGP AD does not come in picture because it is not part of path selection process, as the great Brian McGahan once said: even if you change iBGP AD to 19m BGP will still choose eBGP route if all attributes are equeal to the point where iBGP and eBGP is compared.
given above i get why BGP will choose iBGP route with high local_pref over eBGP, BUT why whould router choose iBGP over OSPF!!, ospf AD is lower than iBGP AD, HELP PLZ!!
