Bandwidth Adaptation for Vertical QoS Mapping in Protocol Stacks for Wireless Links

Telecommunications networks are composed of functional layers acting in cascade. Quality of service (QoS) derives from the action of each layer that must assure a specific level of quality to the upper layer in terms of performance parameters. The action is called vertical QoS mapping and is provided through algorithms that compute the bandwidth necessary so to assure the requested QoS when information is transferred from one layer to the next one below. This paper proposes a scheme that adapts the bandwidth to be allocated to a buffer which conveys heterogeneous traffic (both concerning traffic sources and QoS requirements) in a layer-in-cascade model. The proposed algorithm is based only on measures and does not use closed-form expressions, a-priori information about traffic statistical properties, and assumptions about buffer dimension. It is called WI-RCBC (wireless interface reference chaser bandwidth control).