There is no interconnect between ISP router and there is interconnect between eigrp red routers then topolgy is star and the center is eigrp two router.
There is interconnect between ISP router and there is no interconnect between eigrp router then it as i mention before hub and spoke and spoke is eigrp router but also
Daisy chain between ospf and eigrp router.
Looks like a "real world" hodgepodge (laugh), or a (very) partial mesh, assuming sites with two routers per site also have connectivity to each other, or a hub and spoke if we just consider topology of "sites".
In the "real world", actual topologies, like this, aren't all that uncommon, although such a mixture of static (?) and different routing protocol is not as common (well, except when merging different companies).
I.e. in the "real world" actual networks seldom conform to pristine network topology models, the common reason being, for many reasons, we cannot often just interconnect devices as we might like.
Thank you so much for this explanation. I kept scratching my head when we were asked to mention which network design model we're using. The site with two routers indeed has a dedicated link between them. In case the link fails, traffic is sent via ISP.
The requirements state that two of the locations already have their own infrastructure and would not want to change the routing protocols. I initially thought about a hub and spoke approach where the ISP is in the middle, but the requirement is to have redundancy at Bahrain, so if primary link to the ISP is down than backup can be utilized to get the connectivity to Saudi Arabia and Dubai. In this case, would the hodgepodge approach work or do I have to change it?