Telefonaktiebolaget Lm Ericsson (publ)

Mattias &Ouml;stman

Lars-G&ouml;ran Petersen

Arne Lundb&auml;ck

Johan Mikael Agnevik

Ola Engstr&ouml;m

A queuing system ( ) stores a package ( ) derived from an ATM cell, the package including an internal interface header (IIH) and either an ATM cell payload or an AAL packet. The queuing system comprises a queue ( ) for storing the package, as well as a processor which executes plural functions. A time stamping function applies a time stamp upon storage of the package in the queue. The time stamping function can apply the time stamp to a package as replacement of the internal interface header. A time stamp checking function uses the time stamp to make a determination whether the tenure of the package in the queue is longer than permissible. The time stamp checking function can make the tenure determination in conjunction with a potential readout of the package from the queue. Alternatively, time stamp checking function can make the tenure determination when invoked by a queue monitoring function which monitors a fill level of the queue (e.g., when a queue fill level exceeds a threshold). A discard function is provided for discarding the package if the tenure of the package in the queue is longer than permissible.

ATM time stamped queuing

An ATM switching node has an ATM switch ( ) to which at least one inter-node physical link ( ) is connected. In addition, a cell handling unit ( ) connected to the ATM switch has a centralized queuing resource ( ) which queues ATM cells which are to be routed through the ATM switch for transmission from the node on the physical link. ATM cells destined for the physical link from the queuing resource are discharged from the queuing resource in accordance with a parameter of the physical link. The parameter is preferably the capacity (e.g., transmission rate) of the physical link. In the illustrated embodiment, the node is one of the following nodes of a cellular telecommunications network: a base station ( ); a base station controller ( ); a mobile switching center ( ).

Coordinated cell discharge from ATM queue

An ATM switching node has a queuing resource ( ) connected to an ATM switch core ( ). The queuing resource provides centralized queuing for ATM cells destined for routing through the ATM switch core to plural output links. The ATM switch core routes an ATM cell destined for any output link requiring queuing to the centralized queuing resource. ATM cells for output links not requiring queuing are not directed to the queuing resource. The queuing resource has a link multiplexer ( ) for each output link which is handled by the queuing resource. Each link multiplexer has both a first stage ( ) and a second stage ( ). The second stage comprises plural queues ( ) for storing ATM packets and a second stage multiplexer ( ) for selecting the ATM packets stored in the plural queues of the second stage for transmission to the first stage. The first stage comprises plural queues ( ) for storing ATM cells and a first stage multiplexer ( ) for selection of ATM cells including ATM cells formed of multiplexed ATM packets of the second stage for discharge from the queuing resource. The centralized and selective queuing resource obviates the necessity for queuing at each terminal board connected to the ATM switch core.

Centralized queuing for ATM node

Within an ATM node, a cell handling unit (CHU) receives incoming ATM cells from an ATM switch and provides outgoing ATM cells back to the ATM switch. The cell handling unit consults a combined or consolidated table to obtain ATM parameters (e.g., VCI) for use in headers of outgoing ATM cells. The combined table can be utilized both for ATM cells with AAL2 protocol and ATM cells of a second type AAL protocol. The second type AAL protocol is preferably AAL2 prime, which requires that AAL2 packets carried in the ATM cell payload be whole packets and that the ATM payload not have an AAL2-type start field. The combined table is structured to have plural intervals, including a first interval for AAL2 protocol connections and plural other intervals for the second type AAL protocol connections. Each row for the AAL2 protocol interval associates (1) a unique incoming VCI value; (2) an output link value; (3) an outgoing VCI value; and (4) an offset value. The offset value points to the one of the plural intervals for the second AAL protocol connection. Each of the rows for the table intervals for the second AAL protocol connections associates (1) an incoming VCI value; (2) a channel identifier (CID); (3) an output link value; and (4) an ATM parameter for use in an ATM header of an outgoing ATM cell.

Growing community of inventors

Saltsjöbaden, Sweden

Mattias Östman

Growing community of inventors

Saltsjöbaden, Sweden

Mattias &Ouml;stman

Mattias Östman