These thesis report deals with a range of secure high-speed networking over a metropolitan or wide area. Since this is quite active research area, a full report is given of the interfaces that thrive in removing the bandwidth burden from long distance networks. Only those with the status or potential of a standard are taking into consideration. Next, the position of security is evaluated. It is recommended that the access Interface enjoys certain advantages over the upper layers. Hence, the results of this work are directly applicable to virtually any layered communication architecture. Amongst the security protocols that are available, the IEEE802.11 represents the only viable solution to have the CLS service properly secured. This protocol is designed for a different type of environment and the implications of this are known. In the real sense, IEEE802.11 proves to be a very valuable tool to built multi-level secure private and public networks using the most recent MAN/WAN technologies. Furthermore, it shows how to enhance the security issues related to Metropolitan and Wide Area Network considering the required security services and mechanism.