How to allow OSPF protocol communicate with EIGRP

Redistribute on both routers and ensure you specify the metrics of eigrp so that it can be installed on ospf . and ospf depending on requirements which roytes internal or external and set metrics so eigrp can install them properly you can go further but rule of thumb less distribution is best and most preferred method of good network design

redistribute on the edge of one routing protocol

You have to configure redistribution in order to inject OSPF/EIGRP routes into the routers that are using OSPF/EIGRP protocol.

Redistribution will be configured on the router running both routing protocols.

We need to configure one router to support both protocols i.e 1 interface of that router will run ospf and the other will interface will run eigrp and then you can redistribute between the two so both routing domains have each other networks if they need reachability.

dear all thanks for respond, just more inquire : 

redistribution in one router or both router ? I can do that in same router ?