Some vendors, like Cisco, have proprietary routing protocols that don’t “play well with others” and don’t meet routing standards for interoperability. Other vendors use standard routing protocols. This article on routing protocols might help you better understand the various routing protocols and their differences/similarities. Don’t misunderstand me, Cisco does use standard routing protocols, but like Microsoft, they “embrace and extend” the protocols to “make them work better”.
There’s a lot of information on other questions here about NAT or at SearchEnterpriseWAN that can help you also understand this technology. There is a lot to consider when implementing NAT. These resources will help you.
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