Seems to me the problem is that your router's external address, a.b.c.6 and your firewall's external address, a.b.c.1 cannot be on the same IP subnet, given that your firewall is connected to your router's internal interface.
The a.b.c.1-5 subnet has to be used via NAT in the router.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.