diff --git a/go.mod b/go.mod
index 5d762d7..bd42522 100644
--- a/go.mod
+++ b/go.mod
@@ -5,6 +5,7 @@ go 1.12
 require (
 	github.com/BurntSushi/toml v0.3.1
 	github.com/gorilla/handlers v1.4.0
+	github.com/infobloxopen/go-trees v0.0.0-20190313150506-2af4e13f9062
 	github.com/miekg/dns v1.1.22
 	golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 // indirect
 	golang.org/x/net v0.0.0-20191027093000-83d349e8ac1a
diff --git a/go.sum b/go.sum
index bf8e236..3a21191 100644
--- a/go.sum
+++ b/go.sum
@@ -2,6 +2,8 @@ github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
 github.com/gorilla/handlers v1.4.0 h1:XulKRWSQK5uChr4pEgSE4Tc/OcmnU9GJuSwdog/tZsA=
 github.com/gorilla/handlers v1.4.0/go.mod h1:Qkdc/uu4tH4g6mTK6auzZ766c4CA0Ng8+o/OAirnOIQ=
+github.com/infobloxopen/go-trees v0.0.0-20190313150506-2af4e13f9062 h1:d3VSuNcgTCn21dNMm8g412Fck/XWFmMj4nJhhHT7ZZ0=
+github.com/infobloxopen/go-trees v0.0.0-20190313150506-2af4e13f9062/go.mod h1:PcNJqIlcX/dj3DTG/+QQnRvSgTMG6CLpRMjWcv4+J6w=
 github.com/miekg/dns v1.1.14 h1:wkQWn9wIp4mZbwW8XV6Km6owkvRPbOiV004ZM2CkGvA=
 github.com/miekg/dns v1.1.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
 github.com/miekg/dns v1.1.22 h1:Jm64b3bO9kP43ddLjL2EY3Io6bmy1qGb9Xxz6TqS6rc=
diff --git a/json-dns/globalip.go b/json-dns/globalip.go
index 0122bd3..23b24e4 100644
--- a/json-dns/globalip.go
+++ b/json-dns/globalip.go
@@ -24,106 +24,107 @@
 package jsonDNS
 
 import (
+	"github.com/infobloxopen/go-trees/iptree"
 	"net"
 )
 
-// RFC6890
-var localIPv4Nets = []net.IPNet{
+var defaultFilter *iptree.Tree
+
+func init() {
+	defaultFilter = iptree.NewTree()
+
+	// RFC6890
 	// This host on this network
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{0, 0, 0, 0},
 		net.IPMask{255, 0, 0, 0},
-	},
+	}, struct{}{})
+
 	// Private-Use Networks
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{10, 0, 0, 0},
 		net.IPMask{255, 0, 0, 0},
-	},
+	}, struct{}{})
+
 	// Shared Address Space
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{100, 64, 0, 0},
 		net.IPMask{255, 192, 0, 0},
-	},
+	}, struct{}{})
+
 	// Loopback
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{127, 0, 0, 0},
 		net.IPMask{255, 0, 0, 0},
-	},
+	}, struct{}{})
+
 	// Link Local
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{169, 254, 0, 0},
 		net.IPMask{255, 255, 0, 0},
-	},
+	}, struct{}{})
+
 	// Private-Use Networks
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{172, 16, 0, 0},
 		net.IPMask{255, 240, 0, 0},
-	},
+	}, struct{}{})
+
 	// DS-Lite
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{192, 0, 0, 0},
 		net.IPMask{255, 255, 255, 248},
-	},
+	}, struct{}{})
+
 	// 6to4 Relay Anycast
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{192, 88, 99, 0},
 		net.IPMask{255, 255, 255, 0},
-	},
+	}, struct{}{})
+
 	// Private-Use Networks
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{192, 168, 0, 0},
 		net.IPMask{255, 255, 0, 0},
-	},
+	}, struct{}{})
+
 	// Reserved for Future Use & Limited Broadcast
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{240, 0, 0, 0},
 		net.IPMask{240, 0, 0, 0},
-	},
-}
+	}, struct{}{})
 
-// RFC6890
-var localIPv6Nets = []net.IPNet{
+	// RFC6890
 	// Unspecified & Loopback Address
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
 		net.IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xfe},
-	},
+	}, struct{}{})
+
 	// Discard-Only Prefix
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
 		net.IPMask{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-	},
+	}, struct{}{})
+
 	// Unique-Local
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{0xfc, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
 		net.IPMask{0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-	},
+	}, struct{}{})
+
 	// Linked-Scoped Unicast
-	net.IPNet{
+	defaultFilter.InplaceInsertNet(&net.IPNet{
 		net.IP{0xfe, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
 		net.IPMask{0xff, 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
-	},
+	}, struct{}{})
+
 }
 
 func IsGlobalIP(ip net.IP) bool {
 	if ip == nil {
 		return false
 	}
-	if ipv4 := ip.To4(); len(ipv4) == net.IPv4len {
-		for _, ipnet := range localIPv4Nets {
-			if ipnet.Contains(ip) {
-				return false
-			}
-		}
-		return true
-	}
-	if len(ip) == net.IPv6len {
-		for _, ipnet := range localIPv6Nets {
-			if ipnet.Contains(ip) {
-				return false
-			}
-		}
-		return true
-	}
-	return true
+	_, contained := defaultFilter.GetByIP(ip)
+	return !contained
 }
diff --git a/json-dns/globalip_test.go b/json-dns/globalip_test.go
new file mode 100644
index 0000000..330299f
--- /dev/null
+++ b/json-dns/globalip_test.go
@@ -0,0 +1,15 @@
+package jsonDNS
+
+import (
+	"fmt"
+	"net"
+	"testing"
+)
+
+func TestFindIp(t *testing.T) {
+
+	fmt.Println(IsGlobalIP(net.IP{127, 0, 0, 1}))
+	fmt.Println(IsGlobalIP(net.IP{192, 168, 0, 0}))
+	fmt.Println(IsGlobalIP(net.IP{110, 100, 100, 100}))
+
+}