diff --git a/ryu/lib/packet/bpdu.py b/ryu/lib/packet/bpdu.py
index 0c293cd1..91aefa25 100644
--- a/ryu/lib/packet/bpdu.py
+++ b/ryu/lib/packet/bpdu.py
@@ -145,6 +145,15 @@ TYPE_TOPOLOGY_CHANGE_BPDU = 128
 TYPE_RSTBPDU = 2
 DEFAULT_BRIDGE_PRIORITY = 32768
 DEFAULT_PORT_PRIORITY = 128
+PORT_PATH_COST_100KB = 200000000
+PORT_PATH_COST_1MB = 20000000
+PORT_PATH_COST_10MB = 2000000
+PORT_PATH_COST_100MB = 200000
+PORT_PATH_COST_1GB = 20000
+PORT_PATH_COST_10GB = 2000
+PORT_PATH_COST_100GB = 200
+PORT_PATH_COST_1TB = 20
+PORT_PATH_COST_10TB = 2
 DEFAULT_MAX_AGE = 20
 DEFAULT_HELLO_TIME = 2
 DEFAULT_FORWARD_DELAY = 15