摘要:
An advance over the prior art is achieved through an efficient method for an admission control algorithm and a scheduling mechanism that complement each other in providing the following three classes of service. A first class of service is termed Class 1 where users specify a nominal amount of bandwidth desired. A second, lower tier service class is termed Class 2, wherein users specify a nominal and minimum amount of bandwidth desired when entering into a network connection. A third server class is Class 3, where Class 3 users are treated as best effort users. For Class 1 users the methodology of the present invention provides a guaranteed nominal amount of bandwidth. The admission control procedure ensures that Class 1 users are admitted only if resources exist to satisfy the nominal bandwidth requirements of the Class 1 users. Class 2 users are admitted if resources exist to satisfy the minimum bandwidth requirements of the user. Class 2 users are served with a bandwidth of up to their nominal bandwidths if there is capacity left after serving the Class 1 users with their nominal capacities. Class 3 users are served only if the Class 2 users have received their nominal bandwidths.
摘要:
A rate control system is provided for a link between a first node, such as an RNC and a second node, such as a Node B, within a wireless communications system where at least one user is provided a rate over the link as a function of link load. For example, the rate control system sets at least one user to a reduced rate on the link as a function of the rates of a plurality of users on the link. In certain embodiments, the rate control system controls the rate by selecting the size of a transport format block used to transport data for a user over the link during a transmission interval. The size of the transport format block can be selected by changing the number of transport blocks used to form the transport format block as a function of the total user data to be transported over the link at that time. The rate of data offered to the link can be controlled by the way user data is mapped into the transport format blocks used to send user data over the link. In a current UMTS systems, as long as the data present in a particular RLC buffer exceeds the size of the largest TFB, the largest TFB is used to pass the data to the next layer. With the rate control system, the size of the TFB for a particular user is determined based on the current status of all the RLC buffers that have data to transmit. If there is more data than the Iub link can carry at that point in time, then smaller TFBs are used for some of the users such that the aggregate traffic offered remains below the sustainable rate.
摘要:
In a UMTS (universal mobile telecommunications system) Terrestrial Radio Access Network (UTRAN) based wireless system, a wireless network element (e.g., a base station) exchanges information with another wireless network element (e.g., a radio network controller) via data frames (uplink or downlink). Each data frame comprising a header portion and a payload portion, which comprises a QoS class indicator field. Illustratively, the eight bit spare extension field of a UTRAN data frame (uplink or downlink) is used to convey a four bit payload type indicator and a four bit QoS class indicator.
摘要:
In a UMTS network, each packet data service user requires a dedicated channel (DCH) to transmit at high data rates. However, the number of DCHs available is small due to code and power limitations. Thus many users will have to be allocated the same DCH on a time sharing basis. Such sharing will not impact the quality of service for users whose applications are not delay sensitive and whose traffic generation pattern toggles between transmit and idle states. Such applications include web browsing, FTP sessions and E-mail. The present invention discloses four algorithms that can be used to dynamically allocate DCH channels to a contending user based on the user's need according to its traffic generation. One embodiment of the invention discloses a methodology of allocating user channels for packet data services in a wireless communications network, a first type channel having a given data rate and a second type channel having a lower data rate, including the steps of determining an estimated bandwidth requirement for the packet data services, switching a user to the second channel type from said first channel type if said estimated bandwidth requirement is below a first threshold, and switching a user to the first channel type from said second channel type if the estimated bandwidth requirement is greater than a second threshold. Another embodiment discloses methodology of allocating user channels for packet data services in a wireless communications network, a first type channel having a given data rate and a second type channel having a lower data rate, comprising the steps of providing an inactivity timer per user, and switching from the first channel type to said second channel type depending on a state of said inactivity timer.
摘要:
In a wireless internet access system, an access point of a base station and a group of wireless modems communicate over a wireless channel. This wireless channel comprises a sequence of “dwells,” where each dwell represents a period of time, e.g., 20 milli-seconds (ms). Each dwell can convey both uplink (or upstream) and downlink (or downstream) transmissions to, and from, the group of wireless modems. However, in each dwell a particular wireless modem can only communicate half-duplex—either provide an uplink transmission to the access point, or receive a downlink transmission from the access point. The access point load balances, or distributes, the downlink transmissions to the group of wireless modems across the dwells upon detection that some dwells convey more downlink transmissions than other dwells.