## 2 Literature Review  
This section explores some well-known existing schemes related to the security of TMIS and health care services. In this regard, different 3-PAKE and ECC-based schemes are reviewed to analyze the effectiveness, usefulness, and security strengths for providing reliable security solutions. [PERSON] et al. have proposed an ECC-based efficient 3-PAKE scheme [12] that overcomes the flaws mentioned above but suffers from offline password guessing attacks. [PERSON] et al. have proposed modular exponentiation on an ECC-based 3-PAKE scheme [13] to make it more complicated for the attacker, but these operations require huge computational cost as compared to existing counterparts. [PERSON] et al. have presented the concept of the secret password and smart card-based verification protocol [14] for TMIS by utilizing the discrete hard logarithm problem (DHLP). It pre-registers to stay away from the exponential mathematical computations during authentication stage. In three-party key exchanges (TPKE) [15], [PERSON] et al. has found some flaws in [14] and presented an improved scheme that handles impersonation and insider attacks which made the existing scheme vulnerable. Later on, in scheme [16], [PERSON] et al. explored both [14; 15] schemes and identified the vulnerability of these schemes for offline password guessing attacks, dictionary attacks, and inability to maintain user un-traceability. To overcome these drawbacks, [PERSON] et al. have improved protocols and presented a user authentication scheme for TMIS that can uphold different attacks. Moreover, [PERSON] et al. [17] also identified the offline password guessing attacks in these schemes. To overcome issues in [17], [PERSON] et al. [18] has devised a new user authentication scheme applying smart care which is a user password-based identification that provides user anonymity. This scheme is based on an elliptic curve cryptosystem that provides the same security level as RSA with less key size. [PERSON] et al. [11] highlighted the client anonymity of [PERSON] et al. 's technique [19] but it might be defenseless against insider attacks because all the lawful clients share the secret key. It presented an efficient and secret identity-based validation and secure protocol for TMIS that generates random identities for every exchange in a session to sustain a strategic distance bwetreen individual data about the client and the danger of identity theft attack and ensured that their protocol accomplished client privacy. The scheme is a successor and much preferable to the previous responses for use on mobile devices. The scheme does not provide anonymity of the user and is vulnerable for identity guessing and tracking attacks. In [20] [PERSON] et al. has presented a smart device authentication scheme in a WSN environment and found that these schemes are suitable for TMIS and fulfill all prerequisites for medical device networks. Later on, [PERSON] et al. [21] found that some special insider attacks in medical device networks such as offline password guessing attacks occurred and the system was unable to handle anonymity in [20]. A user anonymous authentication scheme has been presented to handle remote medical services applying in WSN to resolve this issues. [PERSON] et al. [22] pointed out some flaws in [21] for user anonymity and smart card theft. By exploiting symmetric encryption and secure key management for message integrity, [PERSON] et al. [23] presented a temporary credential-based secure key using a one-way hash function and XOR operations. It enhances security fundaments without considerably expanding the memory requirements. In [24], [PERSON] et al. pointed out that scheme [23] is unable to protect against stolen-verifier attacks, denial of service attacks, smart card theft, and participant's signing attacks. [PERSON] et al. presented a secure hash function-based user prediction and secure key management protocol [25] that ensures security with low energy consumption. [PERSON] et al.