I`m sort of new in here, and would like to help me with one thing we need to accomplish as a home work. The question is: Let`s suppose there`s a network consisting of 1000 subnets. How many records would the routing table in each router need to have, if the optimatization doesn`t exist on either of them. The topology is not important here, but what is, is the fact, that every network is connected to two other networks ( it has two outgoing routers with two network interfaces). I`m sorry, but I`m a little bit confused here. Thank you all for help
what do you mean by "optimization doesn't exist on either of them". You mean mechanism like auto-summary or even manual summarization?
If I get your question right... If you want an router to know about every subnet, then you will need 1000 routes as mentioned above.
But if you don't consider summarization to be some optimization mechanism then you could use auto or manual summarization when using dynamic routing.
One more thing, you could add just single route to more networks by defining the route statically.
For example: You want to have an route to networks 192.168.0.0 /24, 192.168.1.0 /24, 192.168.2.0 /24, ..., 192.168.255.0 /24 and you know that these networks resides behind one single router (they are not distributed over more devices) then you could simply add just one ip route to all these networks with mask of /16:
ip route 192.168.0.0 255.255.0.0 next_hop_ip/outoging_interface
So instead of having 255 different entries in the routing table, you could have just one.