diff --git a/imrs/imrs_apnic_list.py b/imrs/imrs_apnic_list.py
new file mode 100644
index 0000000..4981377
--- /dev/null
+++ b/imrs/imrs_apnic_list.py
@@ -0,0 +1,99 @@
+#
+# This script will try to build a sample of the input file.
+# The purpose of the sample is, get a realistic test file
+# that is small enough for iterative development, measures,
+# etc., yet big enough to obtain statistically significant
+# results.
+#
+# Usage: imrs_sample.py <input_file> <sampling rate in %> <output_file>
+#
+
+import sys
+import traceback
+import random
+import time
+import concurrent.futures
+import math
+import os
+from os import listdir
+from os.path import isfile, isdir, join
+
+class imrs_apnic_item:
+    def __init__(self, ip, apnic_use, imrs_use):
+        self.ip = ip
+        self.apnic_use = apnic_use
+        self.imrs_use = imrs_use
+
+    def head():
+        s = "IP, apnic_use, imrs_use,"
+        return s
+
+
+    def text(self):
+        s = ip + "," + str(apnic_use) + "," + str(imrs_use) + ","
+        return s
+
+class apnic_record:
+    def __init__(self):
+        self.ip = ""
+        self.use_count = 0
+        self.seen_in_imrs = False
+        self.imrs_count = 0
+
+    def parse(self, line):
+        parts = line.split(",")
+        nb_parts = len(parts)
+        if nb_parts >= 4:
+            try:
+                self.ip = parts[0].strip()
+                self.use_count = int(parts[3].strip())
+            except Exception as e:
+                traceback.print_exc()
+                print("Cannot parse APNIC Record:\n" + line.strip()  + "\nException: " + str(e))
+                return False
+        return True
+
+def parse_imrs(line):
+    ok = False
+    ip = ""
+    count = 0
+    try:
+        parts = line.split(",")
+        ip = parts[0].strip()
+        count = int(parts[1].strip())
+        ok = True
+    except Exception as e:
+        traceback.print_exc()
+        print("Cannot parse IMRS Record:\n" + line.strip()  + "\nException: " + str(e))
+    return ok, ip, count
+
+
+# main
+
+if len(sys.argv) != 4:
+    print("Usage: imrs_apnic_list.py <imrs_file> <apnic_file> <output_file>")
+    exit(1)
+imrs_file = sys.argv[1]
+apnic_file = sys.argv[2]
+output_file = sys.argv[3]
+
+apnic_dict = dict()
+
+for line in open(apnic_file,"r"):
+    apnic = apnic_record()
+    if apnic.parse(line):
+        apnic_dict[apnic.ip] = apnic
+
+for line in open(imrs_file,"r"):
+    ok, ip, count = parse_imrs(line)
+    if ok:
+        if ip in apnic_dict:
+            apnic_dict[ip].seen_in_imrs = True
+            apnic_dict[ip].imrs_count = count
+
+with open(output_file, "w") as F:
+    F.write("IP, apnic_use, imrs_use,\n")
+    for ip in apnic_dict:
+        apnic_entry = apnic_dict[ip]
+        if apnic_entry.seen_in_imrs:
+            F.write(apnic_entry.ip + "," + str(apnic_entry.use_count) + "," + str(apnic_entry.imrs_count) + "\n")
diff --git a/imrs/imrs_frequency.py b/imrs/imrs_frequency.py
new file mode 100644
index 0000000..97dca88
--- /dev/null
+++ b/imrs/imrs_frequency.py
@@ -0,0 +1,78 @@
+#
+# This script will try to build a sample of the input file.
+# The purpose of the sample is, get a realistic test file
+# that is small enough for iterative development, measures,
+# etc., yet big enough to obtain statistically significant
+# results.
+#
+# Usage: imrs_sample.py <input_file> <sampling rate in %> <output_file>
+#
+
+import sys
+import traceback
+import random
+import time
+import concurrent.futures
+import math
+import os
+from os import listdir
+from os.path import isfile, isdir, join
+
+def parse_imrs(line):
+    ok = False
+    ip = ""
+    count = 0
+    try:
+        parts = line.split(",")
+        ip = parts[0].strip()
+        count = int(parts[1].strip())
+        ok = True
+    except Exception as e:
+        traceback.print_exc()
+        print("Cannot parse IMRS Record:\n" + line.strip()  + "\nException: " + str(e))
+    return ok, ip, count
+
+
+# main
+
+if len(sys.argv) < 3 or len(sys.argv) > 4:
+    print("Usage: imrs_frequency.py <imrs_file> <output_file> [load_step%]")
+    exit(1)
+imrs_file = sys.argv[1]
+output_file = sys.argv[2]
+load_step = 0
+if len(sys.argv) == 4:
+    s_load_step = sys.argv[3]
+    if not s_load_step.endswith("%"):
+        print("Load step should be %, e.g. 1%, 0.1%, not " + s_load_step)
+        exit(1)
+    else:
+        load_step = float(s_load_step[:-1])/100.0
+
+load_vec = []
+
+total_load = 0
+for line in open(imrs_file,"r"):
+    ok, ip, use_count = parse_imrs(line)
+    if ok:
+        load_vec.append(use_count)
+        total_load += use_count
+
+load_vec.sort(reverse=True)
+
+with open(output_file, "w") as F:
+    cumulative_use = 0
+    cumulative_count = 0
+    delta_threshold = int(total_load*load_step)
+    threshold = 0
+    last_written = 0
+    F.write("Count, Queries, frequency,\n")
+    for use_count in load_vec:
+        cumulative_count += 1
+        cumulative_use += use_count
+        if cumulative_use >= threshold:
+            F.write(str(cumulative_count) + "," + str(cumulative_use) + "," + str(cumulative_use/total_load) + ",\n")
+            threshold += delta_threshold
+            last_written = cumulative_count
+    if last_written < cumulative_count:
+        F.write(str(cumulative_count) + "," + str(cumulative_use) + "," + str(cumulative_use/total_load) + ",\n")
\ No newline at end of file
diff --git a/imrs/imrs_record.py b/imrs/imrs_record.py
new file mode 100644
index 0000000..9a6984c
--- /dev/null
+++ b/imrs/imrs_record.py
@@ -0,0 +1,90 @@
+#
+# This script will try to build a sample of the input file.
+# The purpose of the sample is, get a realistic test file
+# that is small enough for iterative development, measures,
+# etc., yet big enough to obtain statistically significant
+# results.
+#
+# Usage: imrs_sample.py <input_file> <sampling rate in %> <output_file>
+#
+
+import sys
+import traceback
+import random
+import time
+import concurrent.futures
+import math
+import os
+from os import listdir
+from os.path import isfile, isdir, join
+
+
+def imrs_parse_one_number(parts, parsed):
+    v = 0
+    p = parts[parsed].strip()
+    v = int(parts[parsed])
+    parsed += 1
+    return v, parsed
+
+def imrs_parse_one_vector(parts, parsed, v):
+    for i in range(0, len(v)):
+        v[i],parsed = imrs_parse_one_number(parts, parsed)
+    return parsed
+
+class imrs_hyperloglog:
+    def __init__(self):
+        self.E = 0.0
+        self.hllv=[0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.0]
+        pass;
+    def parse(self, parts, parsed):
+        self.E = float(parts[parsed].strip())
+        parsed += 1
+        for i in range(0, len(self.hllv)):
+            self.hllv[i], parsed = imrs_parse_one_number(parts,parsed)
+        return parsed
+
+class imrs_record:
+    def __init__(self):
+        self.ip = ""
+        self.query_volume = 0
+        self.hourly_volume = [ 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
+        self.daily_volume = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
+        self.arpa_count = 0
+        self.no_such_domain_queries = 0
+        self.no_such_domain_reserved = 0
+        self.no_such_domain_frequent = 0
+        self.no_such_domain_chromioids = 0
+        self.tld_counts = [0,0,0,0,0,0,0,0]
+        self.tld_hyperlog = imrs_hyperloglog()
+        self.sld_counts = [0,0,0,0,0,0,0,0]
+        self.sld_hyperlog = imrs_hyperloglog()
+        self.name_parts = [0,0,0,0,0,0,0,0]
+        self.rr_types = [0,0,0,0,0,0,0,0]
+        self.locales = [0,0,0,0,0,0,0,0]
+
+    def parse_imrs(self, line):
+        ok = False
+        try:
+            parts = line.split(",")
+            self.ip = parts[0].strip()
+            parsed = 1
+            self.query_volume, parsed = imrs_parse_one_number(parts, parsed)
+            parsed = imrs_parse_one_vector(parts, parsed, self.hourly_volume)
+            parsed = imrs_parse_one_vector(parts, parsed, self.daily_volume)
+            self.arpa_count, parsed = imrs_parse_one_number(parts, parsed)
+            self.no_such_domain_queries, parsed = imrs_parse_one_number(parts, parsed)
+            self.no_such_domain_reserved, parsed = imrs_parse_one_number(parts, parsed)
+            self.no_such_domain_frequent, parsed = imrs_parse_one_number(parts, parsed)
+            self.no_such_domain_chromioids, parsed = imrs_parse_one_number(parts, parsed)
+            parsed = imrs_parse_one_vector(parts, parsed, self.tld_counts)
+            parsed = self.tld_hyperlog = imrs_hyperloglog(parts, parsed)
+            parsed = imrs_parse_one_vector(parts, parsed, self.sld_counts)
+            parsed = self.sld_hyperlog = imrs_hyperloglog(parts, parsed)
+            parsed = imrs_parse_one_vector(parts, parsed, self.name_parts)
+            parsed = imrs_parse_one_vector(parts, parsed, self.rr_types)
+            parsed = imrs_parse_one_vector(parts, parsed, self.locales)
+            ok = True
+        except Exception as e:
+            traceback.print_exc()
+            print("Cannot parse IMRS Record after " + str(parsed) + " parts:\n" + line.strip()  + "\nException: " + str(e))
+        return ok
diff --git a/src/imrs_instances.py b/src/imrs_instances.py
new file mode 100644
index 0000000..6051d40
--- /dev/null
+++ b/src/imrs_instances.py
@@ -0,0 +1,95 @@
+#!/usr/bin/python
+# coding=utf-8
+#
+# This computes the montly totals for all the instances found
+# in the east and west folders. The raw data is organized as:
+# - ipstats / west / one folder per instance / files per date
+#           / east / one folder per instance / files per date
+# The first processing step is to collect the list of file names
+# for each instance: one file per date, possibly more if the
+# same instance is present in east and west.
+#
+#
+
+import sys
+import traceback
+import random
+import time
+import concurrent.futures
+import os
+from os import listdir
+from os.path import isfile, isdir, join
+
+def prepare_instances_list(ipstats_folder, month):
+    instances = dict()
+    for pole in [ "east", "west" ]:
+        pole_dir = join(ipstats_folder, pole)
+        folder_pole = listdir(pole_dir)
+        for instance_id in folder_pole:
+            instance_folder = join(pole_dir, instance_id)
+            if isdir(instance_folder):
+                if not instance_id in instances:
+                    instances[instance_id] = []
+                file_list = listdir(instance_folder)
+                for file_name in file_list:
+                    instances[instance_id].append(join(instance_folder, file_name))
+    return instances
+
+def check_or_create_dir(dir_path):
+    if not isdir(dir_path):
+        try:
+            os.mkdir(dir_path)
+        except Exception as e:
+            traceback.print_exc()
+            print("Cannot create <" + dir_path  + ">\nException: " + str(e))
+            return False
+    return True
+
+def process_instance(instance_id, month, result_folder, tmp_folder, ithitool, instances, do_debug):
+    result_file = instance_id + "_" + month + "-ipstats.csv"
+    result_path = join(result_folder, result_file)
+    tmp_file = instance_id + "_" + month + "-file-list.txt"
+    tmp_path = join(tmp_folder, tmp_file)
+    with open(tmp_path,"wt") as F:
+            for file_name in instances[instance_id]:
+                F.write(file_name + "\n")
+    merge_cmd = ithitool + ' -I ' + result_path + " " + tmp_path
+    cmd_ret = os.system(merge_cmd)
+    if cmd_ret == 0:
+        if do_debug:
+            print(result_file + ": computed.")
+    else:
+        print(result_file + ": computation failed, error:" + str(cmd_ret))
+        return False
+    return True
+
+# main
+if len(sys.argv) < 4 or len(sys.argv) > 5 or \
+    (len(sys.argv) == 5 and sys.argv[4] != "debug"):
+    print("Usage: imrs_instances <ipstats_folder> <yyyymm> <ithitool> [debug]")
+    print("There are just " + str(len(sys.argv)) + " arguments.")
+    exit (1)
+ipstats_folder = sys.argv[1]
+month = sys.argv[2]
+ithitool = sys.argv[3]
+do_debug = len(sys.argv) == 5
+
+print("Writing instance monthly files for: " + ipstats_folder)
+try:
+    instances = prepare_instances_list(ipstats_folder, month)
+    result_folder = join(ipstats_folder, "instances")
+    tmp_folder = join(ipstats_folder, "tmp")
+    if check_or_create_dir(result_folder) and \
+       check_or_create_dir(tmp_folder):
+        for instance_id in instances:
+            if len(instances[instance_id]) > 0:
+                if not process_instance(instance_id, month, result_folder, tmp_folder, ithitool, instances, do_debug):
+                    exit(1)
+except Exception as exc:
+   traceback.print_exc()
+   print('\nCode generated an exception: %s' % (exc))
+
+
+
+
+
diff --git a/src/imrs_monthly_ip.py b/src/imrs_monthly_ip.py
new file mode 100644
index 0000000..7b365c1
--- /dev/null
+++ b/src/imrs_monthly_ip.py
@@ -0,0 +1,110 @@
+#!/usr/bin/python
+# coding=utf-8
+#
+# This processes a list of monthly files (instances or clusters)
+# and extracts a table, with entries:
+# instance, nb_ip, nb_queries
+# or
+# cluster, instances, nb_ip, nb_queries
+# where "nb_ip" is the number of IP addresses seens by this cluster,
+# and "nb_queries" is the total number of queries
+#
+# usage: imrs_montly_ip input_folder output_file
+
+import sys
+import traceback
+import random
+import time
+import concurrent.futures
+import os
+from os import listdir
+from os.path import isfile, isdir, join
+
+def parse_imrs(line):
+    ok = False
+    ip = ""
+    count = 0
+    try:
+        parts = line.split(",")
+        if len(parts) >= 2:
+            ip = parts[0].strip()
+            count = int(parts[1].strip())
+            ok = True
+        else:
+            print("Line <" + line.strip() + " has only " + str(len(parts)) + " parts.")
+    except Exception as e:
+        traceback.print_exc()
+        print("Cannot parse IMRS Record:\n" + line.strip()  + "\nException: " + str(e))
+    return ok, ip, count
+
+# main
+if len(sys.argv) != 3:
+    print("usage: imrs_montly_ip input_folder output_file")
+    exit(1)
+input_folder = sys.argv[1]
+output_file = sys.argv[2]
+is_instances = not input_folder[:-1].endswith("monthly")
+if is_instances:
+    print("From instances monthly, " + input_folder + " compute " + output_file)
+else:
+    print("From cluster monthly, " + input_folder + " compute " + output_file)
+clusters = dict()
+nb_files = 0
+if is_instances:
+    file_list = listdir(input_folder)
+    for file_name in file_list:
+        parts = file_name.split("_")
+        first_parts = parts[0].split('-')
+        if len(first_parts) != 3 or \
+           len(first_parts[0]) != 4 or \
+           len(first_parts[1]) != 2 or \
+           len(first_parts[2]) != 3:
+            print("Cannot get cluster ID from: " + file_name)
+        else:
+            cluster_id = first_parts[1] + "-" + first_parts[2]
+            if not cluster_id in clusters:
+                clusters[cluster_id] = []
+            clusters[cluster_id].append(file_name)
+            nb_files += 1
+else:
+    file_list = listdir(input_folder)
+    for file_name in file_list:
+        parts = file_name.split(".")
+        cluster_id = parts[0]
+        if not cluster_id in clusters:
+            clusters[cluster_id] = []
+        clusters[cluster_id].append(file_name)
+        nb_files +=1
+
+print("Found " + str(len(clusters)) + " clusters, " + str(nb_files) + " files.")
+
+id_list = sorted(list(clusters.keys()))
+
+with open(output_file, "w") as F:
+    F.write("Cluster, Instance, nb_IP, nb_queries,\n")
+    for cluster_id in id_list:
+        sys.stdout.write(cluster_id)
+        total_ip = 0
+        total_queries = 0
+        ip_list = set()
+        for file_name in clusters[cluster_id]:
+            sys.stdout.write(".")
+            sys.stdout.flush()
+            file_path = join(input_folder, file_name)
+            nb_queries = 0
+            nb_ip = 0
+            for line in open(file_path, "r"):
+                ok,ip,count = parse_imrs(line)
+                if ok:
+                    nb_ip += 1
+                    if not ip in ip_list:
+                        ip_list.add(ip)
+                    nb_queries += count
+            if is_instances:
+                file_parts = file_name.split("_")
+                instance_id = file_parts[0]
+                F.write(cluster_id + "," + instance_id + "," + str(nb_ip) + "," + str(nb_queries) + ",\n")
+            total_queries += nb_queries
+        total_ip = len(ip_list)
+        F.write(cluster_id + ",total," + str(total_ip) + "," + str(total_queries) + ",\n")
+    print("\nAll done.")