Threats: Threats to WiMAX

Data Link Layer Threats to WiMAX

In a typical Wi-Fi mechanism, a digital subscriber line (DSL) feeds a packet-ized bit stream into a modem or access point, which in turn broadcasts a radio signal; often encrypted to Wi-Fi enabled clients that de-packet this data into information. In a WiMAX installation, a fixed wireless base station, similar in concept to a cell phone tower, serves an always-on radio signal directly accessible by WiMAX enabled clients, with no need for leased lines or an intermediate access point.

Like Wi-Fi, the WiMax Media Access Control (MAC) protocol, a sub layer of the data link layer, manage the consumer’s access to the physical layer. However, the scheduling algorithm within the WiMAX MAC protocol offers optimal prioritization of this traffic based on First-In First-Out (FIFO) scheduling, in which clients seeking access to the base station are allocated bandwidth upon time of initial access, instead of random queue assignment based on order of MAC address as in Wi-Fi. Furthermore, the WiMax MAC protocol ensures optimal quality of service (QoS) over its WiFi predecessor, allocating bandwidth effectively by balancing client’s needs instead of best effort service; that is, equal distribution of what remains after allocation to other consumers.

In addition, before encrypting the radio signal with Wired Equivalent Privacy (WEP), WPA/PSK, or any other existing Layer 2 security protocol, WiMax basic authentication architecture, by default, employs X.509-based public key infrastructure (PKI) certificate authorization, in which the base station authenticates the client’s digital certificate prior to granting access to the physical layer. (Michel Barbeau, 2005)