diff --git a/common/src/serialize.rs b/common/src/serialize.rs
index bc893f7d0..7b96316ee 100644
--- a/common/src/serialize.rs
+++ b/common/src/serialize.rs
@@ -107,6 +107,19 @@ impl FixedSize for u64 {
     const SIZE_IN_BYTES: usize = 8;
 }
 
+impl BinarySerializable for u128 {
+    fn serialize<W: Write>(&self, writer: &mut W) -> io::Result<()> {
+        writer.write_u128::<Endianness>(*self)
+    }
+    fn deserialize<R: Read>(reader: &mut R) -> io::Result<Self> {
+        reader.read_u128::<Endianness>()
+    }
+}
+
+impl FixedSize for u128 {
+    const SIZE_IN_BYTES: usize = 16;
+}
+
 impl BinarySerializable for f32 {
     fn serialize<W: Write>(&self, writer: &mut W) -> io::Result<()> {
         writer.write_f32::<Endianness>(*self)
diff --git a/src/fastfield/multivalued/reader.rs b/src/fastfield/multivalued/reader.rs
index 994c03c7e..67759b280 100644
--- a/src/fastfield/multivalued/reader.rs
+++ b/src/fastfield/multivalued/reader.rs
@@ -220,8 +220,8 @@ impl<T: MonotonicallyMappableToU128> MultiValueLength for MultiValuedU128FastFie
 ///
 /// Correctness: positions needs to be sorted.
 ///
-/// TODO: Instead of a linear scan we can employ a binary search to match a docid to its value
-/// position.
+/// TODO: Instead of a linear scan we can employ a expotential search into binary search to match a
+/// docid to its value position.
 fn positions_to_docids<T: MultiValueLength>(positions: &[u64], multival_idx: &T) -> Vec<DocId> {
     let mut docs = vec![];
     let mut cur_doc = 0u32;
@@ -250,8 +250,42 @@ fn positions_to_docids<T: MultiValueLength>(positions: &[u64], multival_idx: &T)
 mod tests {
 
     use crate::core::Index;
+    use crate::fastfield::multivalued::reader::positions_to_docids;
+    use crate::fastfield::MultiValueLength;
     use crate::schema::{Cardinality, Facet, FacetOptions, NumericOptions, Schema};
 
+    #[test]
+    fn test_positions_to_docid() {
+        let positions = vec![10u64, 11, 15, 20, 21, 22];
+
+        let offsets = vec![0, 10, 12, 15, 22, 23];
+
+        struct MultiValueLenghtIdx {
+            offsets: Vec<u64>,
+        }
+
+        impl MultiValueLength for MultiValueLenghtIdx {
+            fn get_range(&self, doc_id: crate::DocId) -> std::ops::Range<u64> {
+                let idx = doc_id as u64;
+                let start = self.offsets[idx as usize];
+                let end = self.offsets[idx as usize + 1];
+                start..end
+            }
+
+            fn get_len(&self, _doc_id: crate::DocId) -> u64 {
+                todo!()
+            }
+
+            fn get_total_len(&self) -> u64 {
+                todo!()
+            }
+        }
+
+        let idx = MultiValueLenghtIdx { offsets };
+        let docids = positions_to_docids(&positions, &idx);
+        assert_eq!(docids, vec![1, 3, 4]);
+    }
+
     #[test]
     fn test_multifastfield_reader() -> crate::Result<()> {
         let mut schema_builder = Schema::builder();
diff --git a/src/schema/value.rs b/src/schema/value.rs
index bbd6c4824..559b0f2ea 100644
--- a/src/schema/value.rs
+++ b/src/schema/value.rs
@@ -33,7 +33,7 @@ pub enum Value {
     Bytes(Vec<u8>),
     /// Json object value.
     JsonObject(serde_json::Map<String, serde_json::Value>),
-    /// Ip
+    /// Ip Address value
     IpAddr(IpAddr),
 }
 
@@ -53,7 +53,7 @@ impl Serialize for Value {
             Value::Facet(ref facet) => facet.serialize(serializer),
             Value::Bytes(ref bytes) => serializer.serialize_bytes(bytes),
             Value::JsonObject(ref obj) => obj.serialize(serializer),
-            Value::IpAddr(ref obj) => obj.serialize(serializer), // TODO check serialization
+            Value::IpAddr(ref obj) => obj.serialize(serializer),
         }
     }
 }
@@ -307,11 +307,11 @@ impl From<serde_json::Value> for Value {
 }
 
 mod binary_serialize {
-    use std::io::{self, ErrorKind, Read, Write};
+    use std::io::{self, Read, Write};
     use std::net::IpAddr;
-    use std::str::FromStr;
 
     use common::{f64_to_u64, u64_to_f64, BinarySerializable};
+    use fastfield_codecs::MonotonicallyMappableToU128;
 
     use super::Value;
     use crate::schema::Facet;
@@ -391,7 +391,7 @@ mod binary_serialize {
                 }
                 Value::IpAddr(ref ip) => {
                     IP_CODE.serialize(writer)?;
-                    ip.to_string().serialize(writer) // TODO Check best format
+                    ip.to_u128().serialize(writer)
                 }
             }
         }
@@ -445,7 +445,7 @@ mod binary_serialize {
                         _ => Err(io::Error::new(
                             io::ErrorKind::InvalidData,
                             format!(
-                                "No extened field type is associated with code {:?}",
+                                "No extended field type is associated with code {:?}",
                                 ext_type_code
                             ),
                         )),
@@ -464,10 +464,8 @@ mod binary_serialize {
                     Ok(Value::JsonObject(json_map))
                 }
                 IP_CODE => {
-                    let text = String::deserialize(reader)?;
-                    Ok(Value::IpAddr(IpAddr::from_str(&text).map_err(|err| {
-                        io::Error::new(ErrorKind::Other, err.to_string())
-                    })?))
+                    let value = u128::deserialize(reader)?;
+                    Ok(Value::IpAddr(IpAddr::from_u128(value)))
                 }
 
                 _ => Err(io::Error::new(