Home | Reports | Technical Documents | Tech-Blog | One-Shot Gallery | Korea ICT News | Korea Communication Market Data | List of Contributors | Become a Contributor |    
Section 5G 4G LTE C-RAN/Fronthaul Gigabit Internet IPTV/Video Streaming IoT SDN/NFV Wi-Fi KT SK Telecom LG U+ Network Protocol Samsung   Korean Vendors
Real World Private 5G Cases   4 Deployment Models On-Premise Cases 5G Core Control Plane Sharing Cases

5G Core Sharing Cases

Private 5G Deployment   • Private 5G Frequency Allocation Status in Korea  South Korean government's regulations on private 5G and KT's strategy for entering the market
Cases in Korea   Private 5G Operators |   SK Networks Service (SI) Sejong Telecom (Wire-line Carrier) KT MOS (Affiliate of KT) • Newgens (SI) • NAVER Cloud more >>  
    Enterprise DIY |   Korea Hydro & Nuclear Power (Power Plant) Korea Electric Power Corporation (Energy) • Republic of Korea Navy more >>
CHANNELS     HFR Private 5G Solution (my5G)       my5G Solution Components       my5G Key Features        my5G Resources        my5G News          
What is a Mobile Network composed of
August 28, 2017 | By Abdulaziz Khan @ Mobily
Online viewer:
Comments (9)

We are pleased to share with you all an interesting article contributed by Abdul Aziz Khan who is a Telecom Professional having more than 18 years of diverse Telecom Experience of Planning, Project Management, Optimization and Operations, he is currently working in Network Optimization team of Mobily KSA.


Abdulaziz Khan

Technical Consultant at Mobily



All Articles by Abdulaziz Khan

  How to contribute your article to Netmanias.com !  
  List of Contributors  



An expert mobile user who has good command over his Smartphone often lacks the knowledge of the underlying mobile technology which is helping him in making calls, connecting him to his favorite video or music streaming services, etc. 


Also sometimes I come across my friends who have good command over their mobiles, much more than me at least, and they even work for some mobile companies in a non-technical department, however their knowledge of the technology and the connectivity is quite weak.


When I tried to search internet to find a simple tutorial then I found many good articles on Wikipedia, etc but they were a bit more technical which forced me to contribute to this field, I hope some people will like it, in shaa Allah. 


In order to keep the article brief technical terms used in the tutorial are not explained in further details, the readers who are more interested in these may find Wikipedia and other internet resources more informative.


What is a Mobile Network composed of


A generic Telecom network is composed of different components supplied by a long list of vendors, these networks are organized in an interwoven topology based on the needs of inter-connectivity, Network Security and resilience.


However in order to understand the Telecom Network it can be segregated in a number of Building Blocks each with distinct capabilities and offering different and distinct services to other blocks, also these blocks have distinct interfaces to connect to other blocks with detailed specifications written and agreed through internationally accepted and agreed governing bodies like ITU, IEEE, etc.


Below is a list of generally known blocks and the service they offer and the interfaces they have:


RAN  (Radio Access Network)



RAN is comprised of the equipment that connects the user on Air Interface, in simple words it connects any mobile phone  or data device like tablets to the wireless network, further it aggregates the data from a large number of users and send it towards the core network where the user can get access to different services offered by the Network Operator.


Based on the Wireless Technology RAN equipment can have different names, however from a user's point of view all these components have the similar usability, i.e. to allow the users to use the network services.


RAN network looks very simple in the picture however it is very complex in nature as the connectivity of user to the network is on wireless media and it needs a lot of planning and optimization and thorough drive tests to ensure full network availability in coverage areas because any problem in RAN has its immediate effect on the end user experience.




Transmission is an essential part of Telecom Network, it provides the backbone on which all other blocks connect to each other, in many cases it also provides the connectivity within then blocks as well.


Even though it is not separately mentioned in any of the pictures however the connecting lines in these picture which are within the blocks connecting small blocks and between the blocks may be passing through Transmission devices especially if the entities are not co-located geographically.


Transmission is comprised of many flavors; Physical Infrastructure wise from Coaxial Cables to Microwave Radio to Optical Fiber to VSAT, Technology wise from SDH to ATM to IP/MPLS, capacity wise from Fractional E1 to STM64 and from FE to 400GBPS.


Core Network



Core Network is the heart of the Network and it is most crucial as well because this is where many entities meet. Financially this is most vulnerable area because this is where all data is stored and where charging/billing takes place.


Each component of Core network has a specific thing to do, below we will briefly describe the function of each component:


MSC: Mobile Switching Center, this is where the calls are connected, however this connection is on Circuit Switch basis generally referred as the 2G/3G voice calls.


HLR/VLR: Even though it is not separately shown in the picture but the MSC is connected with two Database servers which hold the User Information, HLR has all the User which are local to the MSC while VLR has the data of the Users that are currently attached to the MSC even if they are not local but on roaming to this network.


HLR/VLR is for 2G and 3G users only, 4G users are provisioned in a different Database name HSS as mentioned below.


SGSN: Serving GPRS Support Node, this is where the data sessions are handled, browsing internet, making video calls is handled here, these sessions/calls are generally referred as Packet Switched as they are based on data packets not mere voice signals.


GGSN: Gateway GPRS Support Node, this is the equipment by which the users are connected to the Internet.


Charging is the component which keeps track of the billing of pre-paid and post paid customers.


ePC: Evolved Packet Core, this is the place where the 4G eNodeBs connect, there is no Packet or Circuit based segregation in ePC as all the users are handled in a data only manner, all voice, video and services are packet data based or generally speaking IP based.


One special ability of ePC is the offloading to the Wi-Fi network, if the LTE network is in congestion or the user is in a area of a better coverage of Wi-Fi or Femtocell then it can be smoothly offloaded to this network bringing ease to the precious LTE air interface to serve other customers.


HSS: This is almost the same Database like HLR/VLR and hold the User Information, the difference is that this Database is for 4G users, it is pertinent to note that a User SIM may be registered on any one or both of the Databases and based on it the services will be provided to him as per the operator's charging policies.


EIR: Equipment Identity Register is a database of the all active mobile handsets, this can be used to track the mobile theft and providing device based services.


AAA: Authentication, Authorization, Accounting server, this is the server where all user records are maintained, the users are authenticated, granted permission to use different resources.


Services/Application Network



These are different entities providing different services to the end users, i.e. the mobile user.


Whatever we do in our Smartphone, from making calls to browsing the internet, sending SMS to chatting on social network, making of video calls to streaming videos is called a service and each service is provided through the services network.


PSTN: Public Switched Telephone Network, this is the service which the user uses to make calls to landline network of the same company whose Mobile service is being used by him.


PLMN: Public Land Mobile Network, this is the interface from where you connect to other Mobile or Fixed Line operators, if you call to other networks then your call is connected through this entity.


Internet: As the name suggests this is from where you connect to the Internet


IMS: IP Multimedia Subsystem, this is your gateway to your operator's IP network, in the present day architecture all the IP services are being converged to an all IP network through IMS, this architecture will ease the way for managing and delivering new services to the end user.


Application Servers: This is the area where your mobile operators has put all the application servers and any user who is trying to access any service is connected to the Application Servers through the IP Multimedia Subsystem.


I hope this topic was useful for a general user to understand the Mobile network in a brief, below is the whole picture integrated together to fully understand end to end.


Picture Source: LTE Testing Brochure from Spirent www.spirent.com

mmsd100 2017-08-28 16:44:28

Excellent report. It is nicely written in a clearer and digestible way, making it easier to understand without getting deeper into 3GPP specifications.

Abdul Aziz Khan 2017-09-17 13:09:58

A must read for the people who want to know the technology wihtout going in the details of it.

Arup (Telstra) via LinkedIn 2017-10-18 19:42:06

Must Read

Tim (Keysight) via LinkedIn 2017-10-23 10:41:29

Excellent! Well-written back to basics.

Roohullah 2018-04-26 16:24:28

Excellent! Thank you so much.


bpaulsson 2018-09-25 18:49:43

Thanks! Very informative!

IDDI SELEMANI 2018-10-22 22:07:08

Well presented..nice and clear..Thanks so much for sharing. Stay blessed chief.

Mohammad Javed 2018-11-20 15:15:48

I must appreciate it, well written and explained.


Farzad Safavinejad 2021-11-27 04:58:03

I appreciate, is there the PDF format of this useful document as well?

Thank you for visiting Netmanias! Please leave your comment if you have a question or suggestion.

[HFR Private 5G: my5G]


Details >>







Subscribe FREE >>

Currently, 55,000+ subscribed to Netmanias.

  • You can get Netmanias Newsletter

  • You can view all netmanias' contents

  • You can download all netmanias'

    contents in pdf file







View All (858)
4.5G (1) 5G (102) AI (8) AR (1) ARP (3) AT&T (1) Akamai (1) Authentication (5) BSS (1) Big Data (2) Billing (1) Blockchain (3) C-RAN/Fronthaul (18) CDN (4) CPRI (4) Carrier Ethernet (3) Charging (1) China (1) China Mobile (2) Cisco (1) Cloud (5) CoMP (6) Connected Car (4) DHCP (5) EDGE (1) Edge Computing (1) Ericsson (2) FTTH (6) GSLB (1) GiGAtopia (2) Gigabit Internet (19) Google (7) Google Global Cache (3) HLS (5) HSDPA (2) HTTP Adaptive Streaming (5) Handover (1) Huawei (1) IEEE 802.1 (1) IP Routing (7) IPTV (21) IoST (3) IoT (56) KT (43) Korea (20) Korea ICT Market (1) Korea ICT Service (13) Korea ICT Vendor (1) LG U+ (18) LSC (1) LTE (78) LTE-A (16) LTE-B (1) LTE-H (2) LTE-M (3) LTE-U (4) LoRa (7) MEC (4) MPLS (2) MPTCP (3) MWC 2015 (8) NB-IoT (6) Netflix (2) Network Protocol (21) Network Slice (1) Network Slicing (4) New Radio (9) Nokia (1) OSPF (2) OTT (3) PCRF (1) Platform (2) Private 5G (11) QoS (3) RCS (4) Railway (1) Roaming (1) SD-WAN (17) SDN/NFV (71) SIM (1) SK Broadband (2) SK Telecom (35) Samsung (5) Security (16) Self-Driving (1) Small Cell (2) Spectrum Sharing (2) Switching (6) TAU (2) UHD (5) VR (2) Video Streaming (12) VoLTE (8) VoWiFi (2) Wi-Fi (31) YouTube (6) blockchain (1) eICIC (1) eMBMS (1) iBeacon (1) security (1) telecoin (1) uCPE (2)
Password confirmation
Please enter your registered comment password.