diff --git a/liteeth/__init__.py b/liteeth/__init__.py
index 3a2180598..e69de29bb 100644
--- a/liteeth/__init__.py
+++ b/liteeth/__init__.py
@@ -1,12 +0,0 @@
-from liteeth.common import *
-from liteeth.mac import LiteEthMAC
-from liteeth.arp import LiteEthARP
-from liteeth.ip import LiteEthIP
-
-class LiteEthIPStack(Module, AutoCSR):
-	def __init__(self, phy, mac_address, ip_address):
-		self.phy = phy
-		self.submodules.mac = mac = LiteEthMAC(phy, 8, interface="crossbar", with_hw_preamble_crc=True)
-		self.submodules.arp = arp = LiteEthARP(mac, mac_address, ip_address)
-		self.submodules.ip = ip = LiteEthIP(mac, mac_address, ip_address, arp.table)
-		self.sink, self.source = self.ip.sink, self.ip.source
diff --git a/liteeth/core/__init__.py b/liteeth/core/__init__.py
new file mode 100644
index 000000000..fa0aaa934
--- /dev/null
+++ b/liteeth/core/__init__.py
@@ -0,0 +1,12 @@
+from liteeth.common import *
+from liteeth.mac import LiteEthMAC
+from liteeth.core.arp import LiteEthARP
+from liteeth.core.ip import LiteEthIP
+
+class LiteEthIPCore(Module, AutoCSR):
+	def __init__(self, phy, mac_address, ip_address):
+		self.phy = phy
+		self.submodules.mac = mac = LiteEthMAC(phy, 8, interface="crossbar", with_hw_preamble_crc=True)
+		self.submodules.arp = arp = LiteEthARP(mac, mac_address, ip_address)
+		self.submodules.ip = ip = LiteEthIP(mac, mac_address, ip_address, arp.table)
+		self.sink, self.source = self.ip.sink, self.ip.source
diff --git a/liteeth/arp/__init__.py b/liteeth/core/arp.py
similarity index 100%
rename from liteeth/arp/__init__.py
rename to liteeth/core/arp.py
diff --git a/liteeth/ip/__init__.py b/liteeth/core/ip.py
similarity index 100%
rename from liteeth/ip/__init__.py
rename to liteeth/core/ip.py
diff --git a/liteeth/udp/__init__.py b/liteeth/core/udp.py
similarity index 100%
rename from liteeth/udp/__init__.py
rename to liteeth/core/udp.py
diff --git a/liteeth/frontend/__init__.py b/liteeth/frontend/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/liteeth/etherbone/__init__.py b/liteeth/frontend/etherbone.py
similarity index 100%
rename from liteeth/etherbone/__init__.py
rename to liteeth/frontend/etherbone.py
diff --git a/liteeth/test/arp_tb.py b/liteeth/test/arp_tb.py
index 484230ec7..1bfd7289b 100644
--- a/liteeth/test/arp_tb.py
+++ b/liteeth/test/arp_tb.py
@@ -5,7 +5,7 @@ from migen.sim.generic import run_simulation
 
 from liteeth.common import *
 from liteeth.mac import LiteEthMAC
-from liteeth.arp import LiteEthARP
+from liteeth.core.arp import LiteEthARP
 
 from liteeth.test.common import *
 from liteeth.test.model import phy, mac, arp
@@ -15,7 +15,7 @@ mac_address = 0x12345678abcd
 
 class TB(Module):
 	def __init__(self):
-		self.submodules.phy_model = phy.PHY(8, debug=True)
+		self.submodules.phy_model = phy.PHY(8, debug=False)
 		self.submodules.mac_model = mac.MAC(self.phy_model, debug=False, loopback=False)
 		self.submodules.arp_model = arp.ARP(self.mac_model, mac_address, ip_address, debug=False)
 
diff --git a/liteeth/test/ip_tb.py b/liteeth/test/ip_tb.py
index 66927654b..1815c243b 100644
--- a/liteeth/test/ip_tb.py
+++ b/liteeth/test/ip_tb.py
@@ -4,7 +4,7 @@ from migen.bus.transactions import *
 from migen.sim.generic import run_simulation
 
 from liteeth.common import *
-from liteeth import LiteEthIPStack
+from liteeth.core import LiteEthIPCore
 
 from liteeth.test.common import *
 from liteeth.test.model import phy, mac, arp, ip
@@ -19,7 +19,7 @@ class TB(Module):
 		self.submodules.arp_model = arp.ARP(self.mac_model, mac_address, ip_address, debug=False)
 		self.submodules.ip_model = ip.IP(self.mac_model, mac_address, ip_address, debug=False, loopback=True)
 
-		self.submodules.ip = LiteEthIPStack(self.phy_model, mac_address, ip_address)
+		self.submodules.ip = LiteEthIPCore(self.phy_model, mac_address, ip_address)
 
 		# use sys_clk for each clock_domain
 		self.clock_domains.cd_eth_rx = ClockDomain()