diff --git a/sisr1/tp07/files_firewall/current_ruleset_v1.nft b/sisr1/tp07/files_firewall/current_ruleset_v1.nft
index 5e456c3..3e35f9b 100644
--- a/sisr1/tp07/files_firewall/current_ruleset_v1.nft
+++ b/sisr1/tp07/files_firewall/current_ruleset_v1.nft
@@ -1,13 +1,17 @@
+define netif = enp0s3
+define dmzif = enp0s8
+define lanif = enp0s9
+
 table ip ipfilter {
 	chain routing {
 		type filter hook forward priority filter; policy accept;
-		icmp type echo-request iif { "enp0s3", "enp0s8" } drop
+		icmp type echo-request iif { $netif, $dmzif } drop
 		icmp type { echo-reply, echo-request } accept
 		drop
 	}
 
 	chain system_in {
 		type filter hook input priority filter; policy accept;
-		icmp type echo-request iif { "enp0s3", "enp0s8" } drop
+		icmp type echo-request iif { $netif, $dmzif } drop
 	}
 }