diff --git a/net/arp/Make.defs b/net/arp/Make.defs
new file mode 100644
index 0000000000..2709b1256b
--- /dev/null
+++ b/net/arp/Make.defs
@@ -0,0 +1,53 @@
+############################################################################
+# net/arp/Make.defs
+#
+#   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 3. Neither the name NuttX nor the names of its contributors may be
+#    used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+NET_ASRCS =
+NET_CSRCS =
+
+ifeq ($(CONFIG_NET),y)
+
+# ARP supported is not provided for SLIP (Ethernet only)
+
+ifneq ($(CONFIG_NET_SLIP),y)
+NET_CSRCS += arp_inout.c arp_table.c arp_timer.c
+
+# Include arp build support
+
+DEPPATH += --dep-path arp
+VPATH += :arp
+CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)net$(DELIM)arp}
+
+endif
+endif
diff --git a/net/igmp/Make.defs b/net/igmp/Make.defs
new file mode 100644
index 0000000000..c401421221
--- /dev/null
+++ b/net/igmp/Make.defs
@@ -0,0 +1,52 @@
+############################################################################
+# net/igmp/Make.defs
+#
+#   Copyright (C) 2014 Gregory Nutt. All rights reserved.
+#   Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in
+#    the documentation and/or other materials provided with the
+#    distribution.
+# 3. Neither the name NuttX nor the names of its contributors may be
+#    used to endorse or promote products derived from this software
+#    without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+ifeq ($(CONFIG_NET),y)
+
+# IGMP source files
+
+ifeq ($(CONFIG_NET_IGMP),y)
+
+NET_CSRCS += igmp_group.c igmp_init.c igmp_input.c igmp_join.c igmp_leave.c
+NET_CSRCS += igmp_mcastmac.c igmp_msg.c igmp_poll.c igmp_send.c igmp_timer.c
+
+# Include igmp build support
+
+DEPPATH += --dep-path igmp
+VPATH += :igmp
+CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)net$(DELIM)uip}
+
+endif
+endif