Evolution of Cellular Systems 27
The authentication server sends the EAP‐Request/AKA‐Challenge message encrypted
by the UE’s public key to the UE. The UE then decrypts the EAP‐Request/AKA‐
Challenge message using its own private key, and then sends the EAP‐Response/
AKA‐Challenge to the authentication server. The authentication server decrypts the
information using the server’s private key and verifies the EAP‐response/AKA‐
Challenge message using the AKA algorithm. If the message is correct, the EAP server
sends the EAP success message to the UE [18].
1.7.5 Security in WiMAX
The IEEE 802.11 security issues were merged by the WiMAX group into IEEE 802.16
standards. This was done because as the WiMAX standard evolved from 802.16 to
802.16a to 802.16e, the requirements evolved from the line‐of‐sight to mobile WiMAX.
Hence, the requirements for security and corresponding standards also evolved to
address the changing demands. In order for the security features of the initial IEEE 802.16
standard to work for the IEEE 802.16e standard, additional features are added [29].
The key new features are listed as follows:
1) Privacy Key Management Version2 (PKMv2) protocol;
2) User authentication is carried out using Extensible Authentication Protocol (EAP)
method;
3) Message authentication is carried out using Hash‐based Message Authentication
Code (HMAC) or Cipher‐based Message Authentication Code (CMAC) scheme; and
4) Confidentiality is achieved using Advance Encryption Standards (AES) [2].
When it comes to WiMAX, over‐the‐air security is a major concern ensuring end‐to‐
end network security. While security architecture has been developed to mitigate
against threats over the air, there still remain a number of challenges. The main challenge seems to be the balance of security needs with the cost of implementation, performance and interoperability. Since WiMAX uses IP transport mechanisms in handling
control/signaling and management traffic, network operators will also have to defend
against general IP security threats [30].
1.8 Conclusion
In this chapter, we presented the evolution of cellular systems. We focused on the development related to radio interface, network architecture and security measurements for
different generation of cellular systems. The very first 1G system to the most recent 4G
system were briefly discussed. The fifth generation (5G) cellular system is the next major
phase of cellular communication, also referred to as wireless technologies beyond 2020.
The 5G standard has to cope with the demand of a 1000‐fold capacity and seamless
connectivity for at least 100 billion devices. A stand‐alone technology will not be able to
cope up with such a demand.
A combination of spectral efficiency, spectrum enhancement and network efficiency,
etc. will meet the challenges of 5G. Various efficient networking technologies, such as
small cells, device‐to‐device (D2D), and software‐defined networks (SDN) technologies
will be adopted. As a part of the spectrum enhancement, the unlicensed bands will be
The authentication server sends the EAP‐Request/AKA‐Challenge message encrypted
by the UE’s public key to the UE. The UE then decrypts the EAP‐Request/AKA‐
Challenge message using its own private key, and then sends the EAP‐Response/
AKA‐Challenge to the authentication server. The authentication server decrypts the
information using the server’s private key and verifies the EAP‐response/AKA‐
Challenge message using the AKA algorithm. If the message is correct, the EAP server
sends the EAP success message to the UE [18].
1.7.5 Security in WiMAX
The IEEE 802.11 security issues were merged by the WiMAX group into IEEE 802.16
standards. This was done because as the WiMAX standard evolved from 802.16 to
802.16a to 802.16e, the requirements evolved from the line‐of‐sight to mobile WiMAX.
Hence, the requirements for security and corresponding standards also evolved to
address the changing demands. In order for the security features of the initial IEEE 802.16
standard to work for the IEEE 802.16e standard, additional features are added [29].
The key new features are listed as follows:
1) Privacy Key Management Version2 (PKMv2) protocol;
2) User authentication is carried out using Extensible Authentication Protocol (EAP)
method;
3) Message authentication is carried out using Hash‐based Message Authentication
Code (HMAC) or Cipher‐based Message Authentication Code (CMAC) scheme; and
4) Confidentiality is achieved using Advance Encryption Standards (AES) [2].
When it comes to WiMAX, over‐the‐air security is a major concern ensuring end‐to‐
end network security. While security architecture has been developed to mitigate
against threats over the air, there still remain a number of challenges. The main challenge seems to be the balance of security needs with the cost of implementation, performance and interoperability. Since WiMAX uses IP transport mechanisms in handling
control/signaling and management traffic, network operators will also have to defend
against general IP security threats [30].
1.8 Conclusion
In this chapter, we presented the evolution of cellular systems. We focused on the development related to radio interface, network architecture and security measurements for
different generation of cellular systems. The very first 1G system to the most recent 4G
system were briefly discussed. The fifth generation (5G) cellular system is the next major
phase of cellular communication, also referred to as wireless technologies beyond 2020.
The 5G standard has to cope with the demand of a 1000‐fold capacity and seamless
connectivity for at least 100 billion devices. A stand‐alone technology will not be able to
cope up with such a demand.
A combination of spectral efficiency, spectrum enhancement and network efficiency,
etc. will meet the challenges of 5G. Various efficient networking technologies, such as
small cells, device‐to‐device (D2D), and software‐defined networks (SDN) technologies
will be adopted. As a part of the spectrum enhancement, the unlicensed bands will be