LTE, LTE-Advanced and WiMAX: Towards IMT-Advanced Networks

6

Quality of Service and Bandwidth Reservation

Four distinct elements are required to provide an effective QoS support in any network. These are:

1. QoS performance measures;
2. Classification;
3. Signaling bandwidth requests and grants; and
4. Bandwidth allocation and traffic handling.

Both IEEE 802.16-2009 and the IEEE 802.16m amendment provide mechanisms that establish these elements at the physical layer and at medium access control layer. In this chapter, we shall have a detailed look at these mechanisms starting with the IEEE 802.16-2009.

This chapter is organized into three sections with the first describing QoS in IEEE 802.16-2009, the second in the IEEE 802.16j-2009 amendment and the third in the IEEE 802.16m amendment. The organization of the individual sections is almost the same, going through a discussion of the bear classification and the signalling require for making bandwidth requests and relaying bandwidth grants. Details for service flow creation, management and deletion then follows. Descriptions of how bandwidth allocations are made and how traffic transmission errors are handled conclude the chapter. Section 6.1, however, differs in defining the QoS performance measures, which apply for both the IEEE 802.16-2009 and its amendments. Meanwhile, Section 6.2 elaborates on differences in bandwidth allocation and handling when IEEE 802.16 relay stations are employed.