Aggregation in IEEE 802.16j Network
The mobile multihop relay-based (MMR) network architecture of IEEE 802.16j imposes a demanding performance requirement on relay stations. We proposed a concatenation and enhanced packing scheme, which incarnates the inherent notion of "aggregation", alleviates the dismal efficiency degradation on relay links, and significantly simplifies the traffic handling at intermediate relay stations.
Background & Objective: The IEEE 802.16j mobile multi-hop relay-based (MMR) network architecture imposes a demanding performance requirement on relay stations. These relays will functionally serve as an aggregating point on behalf of the base station (BS) for traffic collection from and distribution to multiple mobile stations (MSs) associated with the relays, and thus naturally incorporate a notion of "traffic aggregation". However, the legacy concept of connection and the associated packet construction mechanism defined in IEEE 802.16d/16e standard, if applied directly on relay link, may render a potential bottleneck and preponderantly limit the overall network capacity. In order to provide high capacity demanded by relay links, therefore, design of highly efficient connection protocols becomes imperative.
Technical Discussion: As a solution, we proposed a concatenation and enhanced packing scheme, wherein a logical "mega-pipe" (a.k.a. tunnel) is established between access relay station and base station to transport traffic belonging to multiple individual connections. These individual connections to be aggregated can originate from different mobile stations, but shall share some common characteristics (e.g., quality of service (QoS) requirement). The creation, maintenance and identification of such a "mega-pipe", among others, have been optimized so that the efficiency at data plane is substantially improved while the associated overhead in the control plane is minimized, thereby enabling IEEE 802.16j MMR network to deliver a superior performance. Given its nature of aggregation, the proposed scheme also helps simplify the QoS and path management at intermediate relay stations significantly. Moreover, we designed a packet and header format for relay link, which not only enables the operation of connection aggregation, but also supports co-existence of "mega-pipe" and legacy 802.16e connection.
Future Direction: The proposed aggregation protocol and the associated high level packet format design have been accepted into IEEE 802.16j draft standard. Continued participation in future standardization activities is needed. In addition, new contributions will be made to IEEE 802.16j to specify detailed realization and format design.
Contact: Zhifeng (Jeffrey) Tao
| Technical Reports: | |
| Aggregation and Concatenation in IEEE 802.16j Mobile Multihop Relay (MMR) Networks | |
Technology Area: Digital Communications
Modification Date: October 2, 2007
