diff --git a/asn1/MAP-ExtensionDataTypes.asn b/asn1/MAP-ExtensionDataTypes.asn
new file mode 100644
index 0000000..ab4cb9c
--- /dev/null
+++ b/asn1/MAP-ExtensionDataTypes.asn
@@ -0,0 +1,65 @@
+MAP-ExtensionDataTypes {
+   itu-t identified-organization (4) etsi (0) mobileDomain (0)
+   gsm-Network (1) modules (3) map-ExtensionDataTypes (21) version9 (9)}
+
+DEFINITIONS
+
+IMPLICIT TAGS
+
+::=
+
+BEGIN
+
+EXPORTS
+
+	PrivateExtension,
+	ExtensionContainer,
+	SLR-ArgExtensionContainer;
+
+
+-- IOC for private MAP extensions
+
+
+MAP-EXTENSION  ::= CLASS {
+	&ExtensionType				OPTIONAL,
+	&extensionId 	OBJECT IDENTIFIER }
+	-- The length of the Object Identifier shall not exceed 16 octets and the
+	-- number of components of the Object Identifier shall not exceed 16
+
+-- data types
+
+ExtensionContainer ::= SEQUENCE {
+	privateExtensionList	[0]PrivateExtensionList	OPTIONAL, 
+	pcs-Extensions	[1]PCS-Extensions	OPTIONAL,
+	...}
+
+SLR-ArgExtensionContainer ::= SEQUENCE {
+	privateExtensionList	[0]PrivateExtensionList	OPTIONAL, 
+	slr-Arg-PCS-Extensions	[1]SLR-Arg-PCS-Extensions	OPTIONAL,
+	...}
+
+PrivateExtensionList ::= SEQUENCE SIZE (1..maxNumOfPrivateExtensions) OF
+				PrivateExtension
+
+PrivateExtension ::= SEQUENCE {
+	extId		MAP-EXTENSION.&extensionId
+				({ExtensionSet}),
+	extType		MAP-EXTENSION.&ExtensionType
+				({ExtensionSet}{@extId})	OPTIONAL}
+
+maxNumOfPrivateExtensions  INTEGER ::= 10
+
+ExtensionSet		MAP-EXTENSION ::=
+		{...
+		 -- ExtensionSet is the set of all defined private extensions
+	}
+	-- Unsupported private extensions shall be discarded if received.
+
+PCS-Extensions ::= SEQUENCE {
+	...}
+
+SLR-Arg-PCS-Extensions ::= SEQUENCE {
+	...,
+	na-ESRK-Request	[0]	NULL		OPTIONAL }
+
+END