Newbie to security and currently trying to design my home network. I came across an article that stated edge routers should be the first layers of defense, and then it went on in marketing-hype fashion about Cisco IOS Firewall Feature Set.

This had me a bit confused. Is there any real use to having an edge router? I mean some point out that it relieves the load on the firewall itself, but then the edge router would still be congested wouldn't it? If it does packet inspection / filtering, wouldn't it be acting in similar fashion to a firewall? But quite a few sources say an edge router should be the first layer of defense.

Wouldn't be easier, not to mention less expensive, to not place an edge router and instead have the firewall in its place?