diff --git a/backup/export.ldif b/backup/export.ldif
index 9b1ad56..f9f72a8 100644
--- a/backup/export.ldif
+++ b/backup/export.ldif
@@ -35,6 +35,7 @@ dn: cn=seiichi takimoto,cn=users,ou=groups,dc=example,dc=org
 active: TRUE
 cn: seiichi takimoto
 fakecn: FALSE
+device: unknown
 gidnumber: 501
 givenname: seiichi
 homedirectory: /home/users/seiichi
@@ -46,4 +47,4 @@ objectclass: accountsManagement
 sn: takimoto
 uid: seiichi
 uidnumber: 1000
-userpassword: {MD5}Xr4ilOzQ4PCOq3aQ0qbuaQ==
\ No newline at end of file
+userpassword: {MD5}Xr4ilOzQ4PCOq3aQ0qbuaQ==
diff --git a/schema/custom.schema b/schema/custom.schema
index d40bf34..3f8e234 100644
--- a/schema/custom.schema
+++ b/schema/custom.schema
@@ -19,6 +19,11 @@ attributetype     ( 2.25.330098197460787237907941808102951680393.1.1 NAME 'fakeC
         SYNTAX 1.3.6.1.4.1.1466.115.121.1.7
 		SINGLE-VALUE )
 
+attributetype     ( 2.25.330098197460787237907941808102951680393.1.2 NAME 'device'
+		DESC 'Trusted devices info from user-agent'
+        EQUALITY caseIgnoreMatch
+        SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 )
+
 #attributetype     ( 2.25.330098197460787237907941808102951680393.1.2 NAME 'lastAccess'
 #		DESC 'Last access timestamp'
 #        EQUALITY generalizedTimeMatch
@@ -27,5 +32,5 @@ attributetype     ( 2.25.330098197460787237907941808102951680393.1.1 NAME 'fakeC
 
 objectclass 	( 2.25.330098197460787237907941808102951680393.1.2.0 NAME 'accountsManagement' SUP top AUXILIARY
 		DESC 'Accounts management'
-		MUST ( cn $ uid $ active $ fakeCn )
+		MUST ( cn $ uid $ active $ fakeCn $ device )
 		MAY ( userPassword $ description ) )