iSCSI with Multiple NICs

Can anyone point me to good documentation on setting up iSCSI port groups for multiple NICs?

We're using 4 interfaces on each host. Does that mean we need 4 IPs (one for each interface)? Or a single port group and IP that you can add all the interfaces to? Just not sure how to set up the vSwitches and port groups.

Also, do all interfaces get used to increase bandwidth or is it a single active connection?

Thanks,

Scott