Interconnecting BIP-IPs sites | WOM or IPSec?

1) When you say "four BigIP devices", do you mean two pairs (a pair at each site) or four single boxes (4 boxes - 4 sites)?

 

 

2) Please make the goal clearer? Do you want to optimize specific application traffic and use a secure tunnel to do so (WOM)? More of a limited DCI/extended_layer2_vlan situation (WOM)?Or do you want to eventually have many/all subnets route to each other (IPSec) ?

 

 

3) Do you have a VPN network currently? Do you have routers as the demarc for your ISP connections?