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

Quality of Service in IEEE 802.16j

To facilitate MR, the IEEE 802.16j amendment included additional features and specification. However, it does not specify additional QoS parameters to the ones mentioned above. Consequently, we shall start directly at the classification process.

Classification

A MAC PDU crosses a tunnel connection, where it is classified based on the ID of this connection. If it is not addressed to a tunnel connection, it is classified based on its own CID. Note that the connection may be a member of the tunnel. In such a case, the connection PDUs are addressed to the connection's destination and not the tunnel's.

The amendment also defines routing paths between the MR-BS and newly attached MSs or RSs. After it discovers any topology changes due to a node joining or leaving the network, for example, due to mobility, the MR-BS removes an old path or establishes a new one and informs all RSs along that path. A new connection, established along this path, is bound to it using a Path-ID and the CID. Moreover, it can be either, an individual connection or a tunnel connection.

Signaling Bandwidth Requests and Grants

Connections with similar QoS parameters and the same ingress-egress pair join the same connection tunnel. An MR-BS determines the service flow parameters associated with a tunnel and distributes these parameters to all RSs along the tunnel's path. When new connections for an MS are added to or removed from a tunnel, an MR-BS modifies the tunnel's service ...