Along with the ceaseless development of application of mobile networks

higher security is required by many jumped-up services of mobile networks

and therefore

sophisticated security protocols for special cases must be designed to fulfill the demand.Two of these are proposed by Yi Mu and Vijay Varadharajan for end-to-end secret communications between two mobile subscribers in same and different service area respectively.We first analyze the defects of them

then we design two new protocols for the same purpose between inter-domain and intra-domain subscribers respectively

and their performance

especially security

is discussed after this.Compared with original ones

ours are improved not only upon security and other performance

but also on universalism and oneness.