Using /29 netblock with DSL modem, Cisco router and Netscreen Firewall

[confus9d]

Hello,

I'm setting up a new branch office. I have a DSL connection with /29 IP block. A cisco 2801 will be placed in between the DSL modem and a Netscreen 5GT firewall. All three devices need public ip. Now the issue is - I can't assign 2 IP address to the cisco on the same /29 block. One way to get this done is breaking my IP block to 2 seperate /30 blocks and eventually waste some public ips in the process. Is there a way to configure each of this devices to have only one public ip and still have 3 free IPs to be used for devices behind the firewall? Thanks.

 

[brianinms]

Why are you connecting a router in between the modem and your firewall?

 

[confus9d]

to brianms: I'll be connecting a t1 circuit to the router later. Then a vpn tunnel from the firewall will go to our central office. the router will provide failover between the dsl and t1 for my vpn tunnel. this is sort of standard configuration through out the company. hope this explains my situation. thanks.