# Authentication Securing Methods for Mobile Identity: Issues, Solutions and Challenges
## 2 Mobile Authentication Method and Issues
### Securing Authentication for Mobile Networks  
Authentication and key management are critical components of cellular network security because they establish mutual authentication between users and the network \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Authentication** & **Method** & **Issues** & **Risk Level** & **Study** \\ \hline Static password & User enters the username and authenticates using a secret password. & — & Depends on user to memorize, is easy to forget, lose, or leak. & & \\  & Register username and & — & Exposed to guessing, dictionary attack, brute force cracking, stealing, replay attacks, Trojan horse attacks and others. & High & [2,7,11] \\ Dynamic password & Register username and mobile phone number as a primary key. & — & Code is sent in plain text. & \\  & The user’s identification & — & Vulnerability is constantly exposed to high-risk threats. & High & [7] \\  & server’s generated PIN or token. & — & Once breached, it is not available for recovery. The data are not renewable. & & \\  & User captures their biometric information, then preprocess and bind it with user information. & — & Requires high computational cost, accuracy, and usability during the unlocked state, plus hardware sensor devices that are not practical for frequent logins/authentications. & Low & [12,14, 15] \\ Biometric & User registers coordinates of home and office and the trip routes as the initial template, dynamically extended trip regularities. Data acquisition uses mobile GPS to collect the daily trip trajectories, calculate the similarity between the sample and the template trajectories. & — & Frequent changes in user coordinates and stay points for users that travel a lot. & \\ Trajectory & User registers coordinates of home and office and the trip routes as the initial template, dynamically extended trip regularities. Data acquisition uses mobile GPS to collect the daily trip trajectories, calculate the similarity between the sample and the template trajectories. & — & The system has an overhead to be borne when the number of users increases. & Low & [8] \\ Trajectory & User registers coordinates of home and office and the trip routes as the initial template, dynamically extended trip regularities. Data acquisition uses mobile GPS to collect the daily trip trajectories, calculate the similarity between the sample and the template trajectories. & — & The system has an overhead to be borne when the number of users increases. & \\  & User’s geographical location as the identity of the user. Data to be encrypted for a specific location obtained using an anti-spoof GPS receiver that can be identified in terms of space and time. & — & Cost increases and increasingly complex maintenance. & Low & [8] \\ Multi-factor & Combines authentication method used with another layer of authentication. & — & Only applicable when there is a requirement for disabling decryption outside specified geo-location. & Low & [13] \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Authentication comparison. and generate cryptographic keys for the protection of both signaling and user plane data. Each generation of cellular networks has specified at least one type of authentication [19]. For instance, the fourth-generation mobile network (4G) specified 4G EPS-AKA, but the fifth-generation mobile network (5G) specifies three authentication methods: 5G-AKA, EAP-AKA [20], and EAP-TLS (transport layer security) [20]. Because 5G defines additional authentication techniques, wireless practitioners frequently inquire about the rationale for 5G's adoption of these new authentication methods and how they differ from 4G authentication [21]. The purpose of this section is to address those problems by performing a comparative analysis of 4G and 5G mobile authentication methods [22].