diff --git a/modules/net-ncc/main.tf b/modules/net-ncc/main.tf
index 7b861bab..02db91d7 100644
--- a/modules/net-ncc/main.tf
+++ b/modules/net-ncc/main.tf
@@ -15,17 +15,13 @@
  */
 
 locals {
-  spoke_vms = flatten([
-    for spoke_key, spoke in var.spokes : [
-      for nva in spoke.nvas : {
-        ip        = nva.ip
-        vm        = nva.vm
-        vm_name   = element(split("/", nva.vm), length(split("/", nva.vm)) - 1)
-        spoke_key = spoke_key
-        spoke     = spoke
-      }
-    ]
-  ])
+  spoke_vms = [
+    for ras in var.ras : {
+      ip      = ras.ip
+      vm      = ras.vm
+      vm_name = element(split("/", ras.vm), length(split("/", ras.vm)) - 1)
+    }
+  ]
 }
 
 resource "google_network_connectivity_hub" "hub" {
@@ -34,69 +30,65 @@ resource "google_network_connectivity_hub" "hub" {
   description = var.description
 }
 
-resource "google_network_connectivity_spoke" "spoke" {
-  for_each = var.spokes
+resource "google_network_connectivity_spoke" "spoke-ra" {
   project  = var.project_id
   hub      = google_network_connectivity_hub.hub.id
-  location = each.value.region
-  name     = "${var.name}-${each.key}"
+  location = var.region
+  name     = var.name
   linked_router_appliance_instances {
     dynamic "instances" {
-      for_each = each.value.nvas
+      for_each = var.ras
       content {
         virtual_machine = instances.value["vm"]
         ip_address      = instances.value["ip"]
       }
     }
-    site_to_site_data_transfer = false
+    site_to_site_data_transfer = var.data_transfer
   }
 }
 
 resource "google_compute_router" "cr" {
-  for_each = var.spokes
-  project  = var.project_id
-  name     = "${var.name}-${each.key}-cr"
-  network  = each.value.vpc
-  region   = each.value.region
+  project = var.project_id
+  name    = "${var.name}-cr"
+  network = var.vpc
+  region  = var.region
   bgp {
     advertise_mode = (
-      each.value.router.custom_advertise != null ? "CUSTOM" : "DEFAULT"
+      var.custom_advertise != null ? "CUSTOM" : "DEFAULT"
     )
     advertised_groups = (
-      try(each.value.router.custom_advertise.all_subnets, false)
+      try(var.custom_advertise.all_subnets, false)
       ? ["ALL_SUBNETS"] : []
     )
     dynamic "advertised_ip_ranges" {
-      for_each = try(each.value.router.custom_advertise.ip_ranges, {})
+      for_each = try(var.custom_advertise.ip_ranges, {})
       content {
         description = advertised_ip_ranges.key
         range       = advertised_ip_ranges.value
       }
     }
     asn                = var.asn
-    keepalive_interval = try(each.value.router.keepalive, null)
+    keepalive_interval = try(var.keepalive, null)
   }
 }
 
 resource "google_compute_router_interface" "intf1" {
-  for_each           = var.spokes
   project            = var.project_id
   name               = "intf1"
-  router             = google_compute_router.cr[each.key].name
-  region             = each.value.region
-  subnetwork         = each.value.subnetwork
-  private_ip_address = each.value.router.ip1
+  router             = google_compute_router.cr.name
+  region             = var.region
+  subnetwork         = var.subnetwork
+  private_ip_address = var.ip_intf1
 }
 
 resource "google_compute_router_interface" "intf2" {
-  for_each            = var.spokes
   project             = var.project_id
   name                = "intf2"
-  router              = google_compute_router.cr[each.key].name
-  region              = each.value.region
-  subnetwork          = each.value.subnetwork
-  private_ip_address  = each.value.router.ip2
-  redundant_interface = google_compute_router_interface.intf1[each.key].name
+  router              = google_compute_router.cr.name
+  region              = var.region
+  subnetwork          = var.subnetwork
+  private_ip_address  = var.ip_intf2
+  redundant_interface = google_compute_router_interface.intf1.name
 }
 
 resource "google_compute_router_peer" "peer1" {
@@ -105,10 +97,10 @@ resource "google_compute_router_peer" "peer1" {
   }
   project                   = var.project_id
   name                      = "peer1-${each.value.vm_name}"
-  router                    = google_compute_router.cr[each.value.spoke_key].name
-  region                    = each.value.spoke.region
-  interface                 = google_compute_router_interface.intf1[each.value.spoke_key].name
-  peer_asn                  = each.value.spoke.router.peer_asn
+  router                    = google_compute_router.cr.name
+  region                    = var.region
+  interface                 = google_compute_router_interface.intf1.name
+  peer_asn                  = var.peer_asn
   peer_ip_address           = each.value.ip
   router_appliance_instance = each.value.vm
 }
@@ -119,10 +111,10 @@ resource "google_compute_router_peer" "peer2" {
   }
   project                   = var.project_id
   name                      = "peer2-${each.value.vm_name}"
-  router                    = google_compute_router.cr[each.value.spoke_key].name
-  region                    = each.value.spoke.region
-  interface                 = google_compute_router_interface.intf2[each.value.spoke_key].name
-  peer_asn                  = each.value.spoke.router.peer_asn
+  router                    = google_compute_router.cr.name
+  region                    = var.region
+  interface                 = google_compute_router_interface.intf2.name
+  peer_asn                  = var.peer_asn
   peer_ip_address           = each.value.ip
   router_appliance_instance = each.value.vm
 }
diff --git a/modules/net-ncc/variables.tf b/modules/net-ncc/variables.tf
index 2115e2f8..c2639b01 100644
--- a/modules/net-ncc/variables.tf
+++ b/modules/net-ncc/variables.tf
@@ -15,45 +15,78 @@
  */
 
 variable "asn" {
-  description = "ASN for all CRs in the hub."
+  description = "Autonomous System Number for the CR. All spokes in a hub should use the same ASN."
   type        = number
 }
 
+variable "custom_advertise" {
+  description = "IP ranges to advertise if not using default route advertisement (subnet ranges)."
+  type = object({
+    all_subnets = bool
+    ip_ranges   = map(string) # map of descriptions and address ranges
+  })
+}
+
+variable "data_transfer" {
+  description = "Site-to-site data transfer feature, available only in some regions."
+  type        = bool
+}
+
 variable "description" {
   description = "An optional description of the NCC hub."
   type        = string
   default     = "Terraform-managed."
 }
 
+variable "ip_intf1" {
+  description = "IP address for the CR interface 1. It must belong to the primary range of the subnet."
+  type        = string
+}
+
+variable "ip_intf2" {
+  description = "IP address for the CR interface 2. It must belong to the primary range of the subnet."
+  type        = string
+}
+
+variable "keepalive" {
+  description = "The interval in seconds between BGP keepalive messages that are sent to the peer."
+  type        = number
+}
+
 variable "name" {
   description = "The name of the NCC hub being created."
   type        = string
 }
 
+variable "peer_asn" {
+  description = "Peer Autonomous System Number used by the router appliances."
+  type        = number
+}
+
 variable "project_id" {
   description = "The ID of the project where the NCC hub & spokes will be created."
   type        = string
 }
 
-variable "spokes" {
-  description = "List of NCC spokes."
-  type = map(object({
-    vpc        = string
-    region     = string
-    subnetwork = string # URI
-    nvas = list(object({
-      vm = string # URI
-      ip = string
-    }))
-    router = object({
-      custom_advertise = optional(object({
-        all_subnets = bool
-        ip_ranges   = map(string) # map of descriptions and address ranges
-      }))
-      ip1       = string
-      ip2       = string
-      keepalive = optional(number)
-      peer_asn  = number
-    })
+variable "ras" {
+  description = "List of router appliances this spoke is associated with."
+  type = list(object({
+    vm = string # URI
+    ip = string
   }))
 }
+
+variable "region" {
+  description = "Region where the spoke is located."
+  type        = string
+}
+
+variable "subnetwork" {
+  description = "The URI of the subnetwork that CR interfaces belong to."
+  type        = string
+}
+
+variable "vpc" {
+  description = "A reference to the network to which the CR belongs."
+  type        = string
+}