Key Agreement Mean
A key memorandum of understanding is usually called after two parties have been authenticated. The common key agreement allows parties to communicate safely via unreliable communication networks. Definition 2. Protocol is a secure key protocol when (1) the opponent transmits accurate messages. Both and are always accepted and hold the same meeting key, which is evenly distributed; (2) is negligible. We offer a performance comparison between key agreement protocols based on attributes in  and our protocol. Some symbols are defined as: is defined by the number of attributes involved in the system. , are the time of the exhibition operation for an item in the group or in the group. is the time for interconnection. is the number of attributes associated with the data access policy. is the number of attributes associated with the private key. The comparison of computational costs is shown in Table 1.
The KA (Key Agreement) protocol is used to establish secure communication between two or more parties and authenticate entities in an open environment. With the advent of identity cryptography, Smart  introduced the first bipartisan identity-based key memorandum of understanding (ID-KA) that accepted the IBE scheme . Since then, many IDENTIFICATION-KA protocols have been presented successively [1, 8-11]. These IDENTIFICATION-KA protocols have been demonstrated as being safe in different models such as the BJM , br4, CK, etc. Huang and Cao  provided the first detectable IDENTIFICATION-AK protocol in the eCK model . Based on the BJM  model, Chen et al.  proposed the ID-BJM model and built key agreement protocols based on identity. In order to implement detailed access control, session keys are negotiated on the basis of mutual authentication of participant attribute information. many attribute-based Key Agreement (AB-KA) protocols [15-20] are presented. In AB-KA protocols, attribute-based encryption (ABE) plays an important role in protecting secret messages used to generate session keys. ABE  was divided mainly into two categories called ABE (CP-ABE) and key-policy ABE (KP-ABE) breakage codes.
In CP-ABE, the data owner selects an access structure for attributes and encrypts the data with the corresponding attribute of the public key. The access structure is integrated into the encryption text, while the secret key is created based on the data user`s attribute. If a user`s attributes fill the access structure built into the text, he decrypts that encryption text . The KP-ABE scheme is reversed. The encryptor selects descriptive attributes to encrypt the data. Recently, Li et al. [23, 24] presented two CP-ABE schemes with an effective waiver of the attribute that opposes the attack on Dieskokunden`s customers and supports fine grain access control. There are a few decentralized CP-ABE schemes that protect privacy, in which the size of the encryption text increases linearly with the number of attributes built into the access policy. To improve efficiency, Emura et al.  presented a CP-ABE scheme with a constant encryption size. Many EBA schemes [29-38] have been used in different areas of application, such as the EBA, with outsourced data encryption [29, 30, 37], ABE with effective attribute locking , fully verifiable EBA , ABE with keyword search function [29, 31], abeable abeable ABE [32, 33], ABE with leak resistance [34-36], ABE , verifiable, etc.
To solve the important trust problem, Li et al. [39, 40] presented two certificate-based encryption schemes with default security. ABE schemes have a wide application in cloud storage [41, 42], mobile social networks  and smart networks . The original AB-AK protocol  gave a secret handshake mechanism based on attributes. Subsequently, many AB-KA [15-20] protocols were presented. Wang et al.  presented a variant of the AB-KA protocol on the basis of the ABE scheme.