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(obsolete) All-in-one OpenAirInterface eNB+EPC

(updated: 2017, May 8th)

This document explains how to install and configure OAI EPC+eNB on one single Ubuntu 17.04 64 bits machine connected with a regular UE (a Huawei E3272), routing the UE traffic to internet.

The description uses a USRP B210 board.

We also explain how to simplify, fix existing issues, to make a single computer as a full LTE network: EPC+eNB.

Known limitations fixed in the hereafter description

  • OAI EPC require kernel >= 4.7, so we have to use Ubuntu 17.04
  • GTP UDP ports are in conflict for eNB and SGW
  • Useless link between OAI and the Ubuntu/Linux hostname

Install Ubuntu

  • Prepare a machine: a 4 actual cores, no hyper-threading.
    All other configuration OAI Wiki (C1 states, …) describes is about useless.
  • Download Ubuntu 17.04n 64 bits version iso file
  • create a usb key to boot on it
  • install Ubuntu: choose to install Third party SW, and to upgrade all packages while installing
  • do: apt update; apt upgrade until the machine is up-to-date
  • install git and configure your identification in git:
    apt install git
    git config –global user.name “Laurent”
    git config –global user.email “laurent.thomas@open-cells.com”
  • Add the OAI repository as authorized remote system
    echo -n | openssl s_client -showcerts -connect gitlab.eurecom.fr:443 2>/dev/null | sed -ne ‘/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p’ | sudo tee -a /etc/ssl/certs/ca-certificates.crt
  • if you are upset with sudo password, add this line in /etc/sudoers
    • xxxxxxxxxxx ALL=(ALL) NOPASSWD: ALL
    • (xxxxxxxxxxx is your login name)
    • sudo will not ask anymore for a password

Install USRP drivers

Ettus has not yet released their driver for Ubuntu 17.04, we take it from source:

  • sudo apt-get install libboost-all-dev libusb-1.0-0-dev python-mako doxygen python-docutils python-requests cmake build-essential
  • git clone git://github.com/EttusResearch/uhd.git
  • cd uhd; mkdir host/build; cd host/build
  • cmake -DCMAKE_INSTALL_PREFIX=/usr ..
  • make -j4
  • sudo make install
  • sudo ldconfig
  • sudo /usr/lib/uhd/utils/uhd_images_downloader.py

Download & Compile the eNB on 17.04

  • git clone https://gitlab.eurecom.fr/oai/openairinterface5g.git
  • cd openairinterface5g
  • git checkout develop
  • As we already tested and merged in develop updates for Ubuntu 16.10
  • A few updates are required for Ubuntu 17.04
    replace the file cmake_targets/tools/build_helper by: build_helper
  • Now, you should be able to build as usual the eNB
    • source oaienv                                    # configure the shell
    • ./cmake_targets/build_oai -I       # install SW packages from internet
    • ./cmake_targets/build_oai -c -w USRP –eNB –UE # compile eNB

Download and patch EPC

First, clone OAI EPC:
git clone https://gitlab.eurecom.fr/oai/openair-cn.git

I detached the OAI code from any relation between the Linux host name, DNS and the Diameter protocol identifiers such as Realm and end point identifier for diameter protocol

For this, you need to replace with  openair-cn-fixes these files

  • SRC/GTPV1-U/gtp_mod_kernel.[ch] and SRC/GTPV1-U/gtpv1u_task.c
    To use the SPGW destination address parameter. This parameter is already in the config file (but not used in the present EPC code). This enhancement removes the conflict on the same port with the eNB, therefore we can run both SPGW and eNB in the same machine.
  • SRC/S6A/s6a_peer.c
    The modification is only to remove the code that reads Linux host name to overwrite the (correct, already read from the configuration file) diameter id.
  • build_helper: for Ubuntu 17.04 support

Install third party SW for EPC

  • cd openair-cn; source oaienv; cd SCRIPTS
  • ./build_hss -i
    • Answer yes to install: freeDiameter 1.2.0
    • for mysql and phpmyadmin, remember the password you set, it will be mandatory to configure the hss
  • Install 3PP SW for mme and spgw
  • ./build_mme -i ; ./build_spgw -i
    When questions pop-up

    • Don’t re-install ans1c (should have been installed correctly for eNB)
    • Don’t re-install what is already installed
  • Install the GTP kernel module
    • The kernel you have should be 4.10, it contains the Osmocom gtp module
    • This archive contains the module source, patched with the OAI improvements done for kernel 4.7: gtp
      • NO need to download the whole kernel in source to compile a module
        • tar xf gtp_mod.4.10.tgz; cd gtp_mod.4.10
        • make -C /lib/modules/`uname -r`/build M=$PWD
        • sudo cp gtp.ko /lib/modules/`uname -r`/kernel/drivers/net/gtp.ko
      • If you keep Ubuntu up-to-date automatically (default Ubuntu behavior), you’ll need to update the module after each Ubuntu kernel upgrades (each time “uname -r” changes)
      • If you want to use another kernel, you’ll have to merge the file gtp.c with your kernel version source code of gtp.c.
        To help, I’ve let origin 4.10 code in gtp.c.orig

Compile the EPC nodes

No difficulty found in this phase.

  • cd openair-cn; source oaienv; cd SCRIPTS
  • ./build_hss
  • ./build_mme
  • ./build_spgw

Our Network setup description

I’ve made a simple configuration for this all-in-one setup.

Each node is on a separate IP address, this address is used for all it’s interfaces. In our case of all-in-one, we take addresses on the loopback: this will be fine on all your machines.

  • HSS is on localhost: 127.0.0.1
  • eNB is on 127.0.0.10
  • MME is on 127.0.0.20
  • SPGW is on 127.0.0.30

Thanks to the above patch: the diameter configuration is now isolated from Linux hostname.

I’ve chosen: realm for the EPC: “OpenAir5G.Alliance”
So, full distinguish names are:

  • hss.OpenAir5G.Alliance
  • mme.OpenAir5G.Alliance

Install this configuration for eNB

In your eNB configuration file, the network is now fixed, as lo interface always exists and our computer internal addresses also:

////////// MME parameters:
 mme_ip_address = ( { ipv4 = "127.0.0.20";
 ipv6 = "192:168:30::17";
 active = "yes";
 preference = "ipv4";
 }
 );

NETWORK_INTERFACES : 
 {
 ENB_INTERFACE_NAME_FOR_S1_MME = "lo";
 ENB_IPV4_ADDRESS_FOR_S1_MME = "127.0.0.10/8";

ENB_INTERFACE_NAME_FOR_S1U = "lo";
 ENB_IPV4_ADDRESS_FOR_S1U = "127.0.0.10/8";
 ENB_PORT_FOR_S1U = 2152; # Spec 2152
 };

In the eNB config file, you need also to set the MCC and MNC as per your SIM card:

tracking_area_code = “1”;
mobile_country_code = “208”;
mobile_network_code = “92”;

And obviously, your radio parameters.

Install this configuration for EPC

For the EPC, we install in OAI default directory: /usr/local/etc/oai this tar file: oai.config

Then, you should generate the cyphering certificates:

  • cd openair-cn; source oaienv; cd SCRIPTS
  • ./check_hss_s6a_certificate /usr/local/etc/oai/freeDiameter hss.OpenAir5G.Alliance
  • ./check_mme_s6a_certificate /usr/local/etc/oai/freeDiameter mme.OpenAir5G.Alliance

Only the SGi output to internet need to be configured.
In /usr/local/etc/oai/spgw.conf,
your should set the Ethernet interface that is connected to Internet, and,
to tell to the PGW to implement NAPT for the UE traffic

 PGW_INTERFACE_NAME_FOR_SGI = "enp3s0"; 
 PGW_MASQUERADE_SGI = "yes";

For the SIM card, you’ll have more to do:

  • SIM MCC/MNC should be duplicated
    • eNB: See above in eNB configuration chapter
    • MME
      • file: /usr/local/etc/oai/mme.conf to update
        • GUMMEI_LIST = ( MCC=”208″ ; MNC=”92″; MME_GID=”4″ ; MME_CODE=”1″; } );
        • TAI_LIST = ({MCC=”208″ ; MNC=”92″; TAC = “1”; } );
        • S-GW_LIST_SELECTION = (
          {ID=”tac-lb01.tac-hb00.tac.epc.mnc092.mcc208.3gppnetwork.org” ; SGW_IPV4_ADDRESS_FOR_S11=”127.0.0.30/8″;}
          );
    • HSS
      • Configure the password for MySQL
        • in /usr/local/etc/oai/hss.conf, set user as root and password as the password you created during MySQL installation
      • A HSS database in text is in: /usr/local/etc/oai/opencells_db.sql
        • It is preconfigured with the mme id, the pgw id
        • A SIM user in network 001/01 (the test network defined by 3GGP) is already created.
        • 10 users is network 208/92 (a French test network) are also created
        • Each time you import this db, it erases the entire database
          (example: mysql user=root, password=linux)

          • ./hss_db_import 127.0.0.1 root linux oai_db /usr/local/etc/oai/opencells_db.sql
        • One can modify the db either with a text editor of this file, or ,
          by sql: http://localhost/phpmyadmin
        • The important values to set are:
          • table pdn:
            • all IMSI are listed, with the APN: these values are in UE/SIM
          • table users:
            • all IMSI are, key (Ki) and OPc must be the same in USIM card.
              Sqn increments when the UE authenticate,
              it should be set as per USIM internal incrementation
      • SIM card update
        • will be described later, for Open cells UICC and card reader

Final test and verification

open 4 terminal windows

  1. in first window
    • cd openair-cn; source oaienv; cd SCRIPTS; ./run_hss
  2. in second window
    • cd openair-cn; source oaienv; cd SCRIPTS; ./run_mme
  3. in third window
    • cd openair-cn; source oaienv; cd SCRIPTS; sudo -E ./run_spgw
  4. in last windows
    • sudo bash
    • cd openairinterface5g; source oaienv;
    • export LD_LIBRARY_PATH=/usr/local/lib/:./targets/bin;
    • ./cmake_targets/lte_build_oai/build/lte-softmodem -d -O <your config file>
  5. Connect the UE, it should attach to network and be able to reach internet through OAI network
  6. Enjoy