Performance Improvements

I am currently using the code below in an application which I am trying to enhance performance.  I am looking for suggestions for improving performance of this code. The database being used has one table named Country, with three columns named LIP1, LIP2, and countryname.

    Public Function IPLookup(ByVal DottedIP As String) As String
        Dim lngIP As Long
        Dim strCountry As String
        Dim con As New OleDbConnection
        Dim dtm As DataTableMapping
        Dim da As New OleDbDataAdapter
        Dim cmdSelect As New OleDbCommand
        Dim ds As New DataSet
        Dim dt As DataTable

        lngIP = Dot2LongIP(DottedIP)
        con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source = C:\resource\master.mdb"
        dtm = da.TableMappings.Add("Table", "Country")
        cmdSelect.CommandText = "SELECT countryname FROM Country WHERE " & lngIP.ToString & " >= ipl1 and " _
                   & lngIP.ToString & "  <= ipl2"

        cmdSelect.Connection = con
        da.SelectCommand = cmdSelect
        da.Fill(ds)
        dt = ds.Tables("Country")
        If dt.Rows.Count = 0 Then
            strCountry = "Unknown"
        Else
            strCountry = dt.Rows(0).Item("countryname")
        End If

        Return strCountry
    End Function
End Class


Thank you very time and expertise,
Gr8life