Patent Abstract:
A wireless telecommunication system, a node (e.g., eNodeB, BSC, RNC), a procedure latency monitor unit, and a method are described herein for measuring the latency of a procedure (e.g., radio network procedure, core network procedure) where the results of the measured latency may be used for admission control of user equipment (UE) sessions and to guarantee that admitted UEs are served according to their requested Quality of Service (QoS).

Full Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of International Application No. PCT/SE2011/051025, filed Aug. 25, 2011, the disclosure of which is fully incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a wireless telecommunication system, a node (e.g., eNodeB, eNB, BSC, RNC), a procedure latency monitor unit, and a method for measuring the latency of a procedure e.g., radio network procedure, core network procedure where the results of the measured latency may be used for admission control of user equipment (UE) sessions and to guarantee that admitted UEs are served according to their requested Quality of Service (QoS). 
       BACKGROUND 
       [0003]    The following abbreviations are herewith defined, at least some of which are referred to within the following description about at least the prior art and/or the present invention.
   BSC Base Station Controller   CDMA Code Division Multiple Access   CN Core Network   CPU Central Processing Unit   EPC Evolved Packet Core   ERAB EUTRAN Radio Access Bearers   GSM Global System for Mobile Communications   LTE Long Term Evolution   PLM Procedure Latency Monitor   PRB Physical Resource Block   QoS Quality of Service   RAN Radio Access Network   RNC Radio Network Controller   RRC Radio Resource Control   tPLM Procedure Latency Mean time   UE User Equipment   WCDMA Wideband Code Division Multiple Access   
 
         [0021]    In a wireless telecommunication system, admission control (capacity management) is a function implemented in the node (e.g., eNodeB, BSC, RNC) that manages a number of UE sessions. Admission control is needed to handle new, ongoing and incoming UE connections due to e.g. handover or roaming or establishment of connections, and to guarantee that admitted UEs are served according to their requested Quality of Service (QoS). In addition, admission control is needed when the offered load is much higher than the node&#39;s engineered capacity. For example, when the node (e.g., eNodeB, BSC, RNC) encounters a situation with high load, the node&#39;s admission control mechanism has the responsibility to throttle (e.g., reduce) the load so it remains within the node&#39;s engineered capacity. This is valid for ongoing, new and incoming UE connections due to e.g. handover. 
         [0022]    For example, in LTE the eNodeB&#39;s admission control mechanism uses both hard limits (e.g., the number of licenses in use) and dynamic limits (e.g., the utilization ratio of the PRB resources). Basically, the eNodeB is configured to implement its own utilization measure for each internal resource that is a potential bottleneck. And, during the eNodeB operation a different type of traffic pattern will create its own particular bottlenecks. Thus, when designing and programming or configuring the eNodeB it is difficult to predict which internal resources that will run out due to high traffic load and which internal resources that need to be monitored. The eNodeB&#39;s internal resources may be for example:
       Number of connected users   Number of bearers per user (signaling and data)   CPU utilization   Signal buffer sizes       
 
         [0027]    Accordingly, there is and has been a need for enhancing the traditional node (e.g., eNodeB, BSC, RNC) to address these shortcomings and other shortcomings to improve at least the admission control function to handle new, ongoing and incoming UE connections. This need and other needs are satisfied by the exemplary embodiments of the present invention. 
       SUMMARY 
       [0028]    A node (e.g., eNodeB, eNB, BSC, RNC), a procedure latency monitor unit, a method, and a wireless telecommunication system that address the shortcomings of the prior art are described in the independent claims of the present application. Advantageous embodiments of the node (e.g., eNodeB, eNB, BSC, RNC), the procedure latency monitor unit, the method, and the wireless telecommunication system have been described in the dependent claims of the present application. 
         [0029]    In an aspect of exemplary embodiments of the present invention there is provided a node (e.g., eNodeB, eNB, BSC, RNC) located in a wireless telecommunications network and configured to administer a number of sessions with UEs. The node comprises a procedure latency monitor unit and an admission control mechanism. The procedure latency monitor unit is configured to establish a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window is further configured to measure a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure. In addition, the procedure latency monitor unit upon completion of the measurement window is configured to take the predetermined number of measured delta times and is further configured to calculate a mean delta time which is an average of the measured delta times. Furthermore, the procedure latency monitor unit is configured to compare the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then the procedure latency monitor unit is configured to issue a high load signal associated with the procedure. The admission control mechanism is configured to receive the high load signal associated with the procedure and is further configured to activate an admission action. An advantage of the node is that it may better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0030]    In yet another aspect of exemplary embodiments of the present invention there is provided a method implemented by a node (e.g., eNodeB, eNB, BSC, RNC) located in a wireless telecommunications network and configured to administer a number of sessions with UEs. The method comprises: (a) establishing, in a procedure latency monitor unit, a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window measuring a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) taking, in the procedure latency monitor unit, the predetermined number of measured delta times upon completion of the measurement window and calculating a mean delta time which is an average of the measured delta times; (c) comparing, in the procedure latency monitor unit, the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then issuing a high load signal associated with the procedure; and (d) receiving, at an admission control mechanism, the high load signal associated with the procedure then activating an admission action. An advantage of the method is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0031]    In still yet another aspect of exemplary embodiments of the present invention there is provided a procedure latency monitor unit which is part of a wireless telecommunication network. The procedure latency monitor unit comprises a processor and a memory that stores processor-executable instructions therein where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (a) establish a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window measure a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) take the predetermined number of measured delta times upon completion of the measurement window and calculate a mean delta time which is an average of the measured delta times; and (c) compare the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then issue a high load signal associated with the procedure. An advantage of the procedure latency monitor unit is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0032]    In yet another aspect of exemplary embodiments of the present invention there is provided a method implemented by a procedure latency monitor unit which is located in a wireless telecommunications network. The method comprises: (a) establishing a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window measuring a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) taking the predetermined number of measured delta times upon completion of the measurement window and calculating a mean delta time which is an average of the measured delta times; and (c) comparing the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then issuing a high load signal associated with the procedure. An advantage of the method is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0033]    In still yet another aspect of exemplary embodiments of the present invention there is provided a wireless telecommunications network which comprises a core network and a node (e.g., eNodeB, eNB, BSC, RNC) connected to the core network and configured to administer a number of sessions with UEs. The node comprises a procedure latency monitor unit and an admission control mechanism. The procedure latency monitor unit is configured to establish a measurement window associated with a procedure within the wireless telecommunications network and during the measurement window is further configured to measure a predetermined number of delta times, where each measured delta time indicates an amount of time that takes place between a start of the procedure and a stop of the procedure. In addition, the procedure latency monitor unit upon completion of the measurement window is configured to take the predetermined number of measured delta times and is further configured to calculate a mean delta time which is an average of the measured delta times. Furthermore, the procedure latency monitor unit is configured to compare the mean delta time with a predetermined threshold which is also associated with the procedure and if the mean delta time exceeds the threshold then the procedure latency monitor unit is configured to issue a high load signal associated with the procedure. The admission control mechanism is configured to receive the high load signal associated with the procedure and is further configured to activate an admission action. An advantage of the node is that it may better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0034]    In yet another aspect there is provided a procedure latency monitor unit which is located in a wireless telecommunications network. The procedure latency monitor unit comprises a processor and a memory that stores processor-executable instructions therein where the processor interfaces with the memory and executes the processor-executable instructions to enable the following: (a) establish a measurement window when a procedure in the wireless telecommunications network has a delta time that exceeds a predetermined threshold, where the delta time is an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) set a number of delta time measurements for the procedure that are to be completed during the measurement window; (c) wait for the procedure to occur; (d) when the procedure occurs, calculate a delta time which indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (e) decrement by one the number of delta time measurements that need to be completed during the measurement window; (f) determine if completed all of the delta time measurements that were set to be completed during the measurement window; (g) if the result of the determine step is no, then return and perform the wait operation; (h) if the result of the determine step is yes, then: (i) stop the delta time measurement; (ii) calculate a mean delta time which is an average of the measured delta times for the procedure; (iii) check if the mean delta time exceeds a predetermined threshold which is associated with the procedure; (iv) if the result of the check operation is yes, then send a high load signal associated with the procedure; and (v) if the result of the check operation is no, then determine if there is an outstanding high load signal and if not then end otherwise send a cease high load signal associated with the procedure. An advantage of the procedure latency monitor unit is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0035]    In still yet another aspect of exemplary embodiments of the present invention there is provided a method implemented by a procedure latency monitor unit which is located in a wireless telecommunications network. The method comprises: (a) establishing a measurement window when a procedure in the wireless telecommunications network has a delta time that exceeds a predetermined threshold, where the delta time is an amount of time that takes place between a start of the procedure and a stop of the procedure; (b) setting a number of delta time measurements for the procedure that are to be completed during the measurement window; (c) waiting for the procedure to occur; (d) when the procedure occurs, calculating a delta time which indicates an amount of time that takes place between a start of the procedure and a stop of the procedure; (e) decrementing by one the number of delta time measurements that need to be completed during the measurement window; (f) determining if completed all of the delta time measurements that were set to be completed during the measurement window; (g) if the result of the determining step is no, then return and perform the waiting step; (h) if the result of the determining step is yes, then: (i) stopping the delta time measurement; (ii) calculating a mean delta time which is an average of the measured delta times for the procedure; (iii) checking if the mean delta time exceeds a predetermined threshold which is associated with the procedure; (iv) if the result of the checking step is yes, then sending a high load signal associated with the procedure; and (v) if the result of the checking is no, then determining if there is an outstanding high load signal and if not then end otherwise sending a cease high load signal associated with the procedure. An advantage of the method is that it enables the node to better steer the admission control function and determine when an internal resource has reached its engineered capacity. 
         [0036]    Additional aspects will be set forth, in part, in the detailed description, figures and any claims which follow, and in part will be derived from the detailed description, or may be learned by practice of the exemplary embodiments of the present invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as disclosed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0037]    A more complete understanding of the presently described embodiments may be obtained by reference to the following detailed description when taken in conjunction with the accompanying drawings: 
           [0038]      FIG. 1  is a block diagram of an exemplary LTE wireless telecommunication system which has eNodeBs configured in accordance with an embodiment of the present invention; 
           [0039]      FIG. 2  is a block diagram that illustrates in greater detail the components in one of the eNodeBs shown in  FIG. 1  configured in accordance with an embodiment of the present invention; 
           [0040]      FIG. 3  is a flowchart illustrating the basic steps of an exemplary method implemented by a procedure latency monitor unit (incorporated within the eNodeB) in accordance with an embodiment of the present invention; 
           [0041]      FIG. 4  is a diagram illustrating used to help explain how the procedure latency monitor unit (incorporated within the eNodeB) may perform a latency procedure measurement in accordance with an embodiment of the present invention; and 
           [0042]      FIG. 5  is a flowchart illustrating the basic steps of another exemplary method implemented by the procedure latency monitor unit (incorporated within the eNodeB) in accordance with an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0043]    Referring to  FIG. 1 , there is a block diagram of an exemplary LTE wireless telecommunication system  100  which has eNodeBs  102   a ,  102   b  and  102   c  (only three shown) each configured in accordance with an embodiment of the present invention. In this example, the LTE wireless telecommunication system  100  includes a MME/S-GW  104  (e.g., core network  104 ) which has Si interfaces with the three eNodeBs  102   a ,  102   b  and  102   c . The eNodeBs  102   a ,  102   b  and  102   c  respectively manage their own cells  106   a ,  106   b  and  106   c  which have their own radio cover areas within which there may be one or more UEs  108 . The eNodeBs  102   a ,  102   b  and  102   c  utilize RRC signaling to interface with their respective UEs  108 . In addition, the eNodeBs  102   a ,  102   b  and  102   c  communicate with one another over multiple X2 interfaces. The exemplary LTE wireless telecommunication system  100  may support many UEs  108  and includes many other components which are well known in the art but for clarity are not described herein while the eNodeBs  102   a ,  102   b  and  102   c  or nodes in accordance with the presently described exemplary embodiments are described in detail herein. A detailed description is provided next to explain how the eNodeBs  102   a ,  102   b  and  102   c  are configured to address the shortcomings of the prior art and improve the admission control function to better handle new, ongoing and incoming UE connections. The eNodeBs  102   a ,  102   b  and  102   c  also have many well known components (e.g., receiver, transmitter) incorporated therein but for clarity those well known components are not described herein. 
         [0044]    Referring to  FIGS. 2 and 3 , there are shown a block diagram and a flowchart respectively illustrating the eNodeB  102   a  (for example) and the method  300  implemented therein in accordance with an exemplary embodiment of the present invention. As shown, the eNodeB  102   a  includes an admission control mechanism  202 , a procedure latency monitor unit  204 , and an optional traffic measurement unit  206 . The procedure latency monitor unit  204  includes a processor  208  and a memory  210  that stores processor-executable instructions therein where the processor  208  interfaces with the memory  210  and executes the processor-executable instructions to enable the following: (a) establish a measurement window  212  associated with a procedure  214  within the wireless telecommunications network  100  and during the measurement window  212  measures a predetermined number of delta times  216 , where each measured delta time  216  indicates an amount of time that takes place between a start  218  of the procedure  214  and a stop  220  of the procedure  214  (step  302  in FIG.  3 )(see also description associated with  FIG. 4 ); (b) take the predetermined number of measured delta times  216  upon completion of the measurement window  212  and calculate a mean delta time  222  which is an average of the measured delta times  216  (see step  304  in  FIG. 3 ); and (c) compare the mean delta time  222  with a predetermined threshold  224  which is also associated with the procedure  214  and if the mean delta time  222  exceeds the threshold  224  then issue a high load signal  226  (e.g., raiseHighLoad (procedure)  226 ) associated with the procedure  214  (step  306  in  FIG. 3 ). Thereafter, the admission control unit  202  upon receiving the high load signal  226  (e.g., raiseHighLoad (procedure)  226 ) associated with the procedure  214  is configured to activate an admission action  228 . 
         [0045]    The traffic measurement unit  206  may be used in conjunction with the procedure latency monitor unit  204  to provide additional information  230  (e.g., dropped UE sessions  230 ) to the admission control mechanism  202 . For example, the traffic measurement unit  206  may be configured to determine the number of sessions with the UEs  108  which are dropped without being requested to be released by the UEs  108  and then report the number of dropped UE sessions  230  to the admission control mechanism  202 . Thereafter, the admission control mechanism  202  upon receiving the high load signal  226  associated with the procedure  214  further determines if the number of dropped UE sessions  230  exceeds a predetermined threshold  232  and if yes then activates the admission action  228 . For example, the admission action  228  may include anyone or a combination of the following:
       Block one or more new UEs trying to connect to the eNodeB level.   Release one or more UEs  108  already connected based on a priority class;   Block a new data radio bearer setup.   Release of one or more data radio bearers.   Reduce observability monitoring.   Etc.       
 
         [0052]    If desired, the procedure latency monitor unit  204  may establish additional measurement windows  212 ′ to measure additional delta times  216 ′ for additional different procedures  214 ′ and then calculate additional mean delta times  222 ′ for the additional different procedures  214 ′ where if one or more of the calculated mean delta times  222 ′ exceed a corresponding threshold  224 ′ then issue one or more high load signals  226  associated with the corresponding one or more different procedures  214 ′. In particular, the procedure latency monitor unit  204  for each additional monitored procedure  214 ′ would: (a) establish a measurement window  212 ′ associated with that procedure  214 ′ within the wireless telecommunications network  100  and during the measurement window  212 ′ measures a predetermined number of delta times  216 ′, where each measured delta time  216 ′ indicates an amount of time that takes place between a start  218 ′ of that procedure  214 ′ and a stop  220 ′ of that procedure  214 ′; (b) take the predetermined number of measured delta times  216 ′ upon completion of the measurement window  212 ′ and calculate a mean delta time  222 ′ which is an average of the measured delta times  216 ′; and (c) compare the mean delta time  222 ′ with a predetermined threshold  224 ′ which is also associated with that procedure  214 ′ and if the mean delta time  222 ′ exceeds the threshold  224 ′ then issue a high load signal  226  (e.g., raiseHighLoad (procedure)  226 ) associated with the procedure  214 ′. For example, the procedure latency monitor unit  204  may monitor one or more procedures  214  and  214 ′ which include radio network procedures and/or core network procedures such as anyone of the following:
       a RRCConnectionSetup.   an InitialContextSetup.   an ERABSetup.   a HandoverPreparation.   A procedure that interacts with another node other than UEs  108 .   Etc.       
 
         [0059]    Once, the procedure latency monitor unit  204  issues the high load signal  226  which is associated with anyone of the procedures  214  or  214 ′ then the processor  208  may further execute the processor-executable instructions to establish another measurement window  212  or  212 ′ for that procedure  214  or  214 ′ to measure multiple delta times  216  or  216 ′ for that procedure  214  or  214 ′ and then calculate the mean delta time  222  or  222 ′ for that procedure  214  or  214 ′ where if the calculated mean delta time  222  or  222 ′ does not exceed the threshold  224  or  224 ′ for that procedure  214  or  214 ′ then issue a cease high load signal  234  (e.g., ceaseHighLoad (procedure)  234 ) associated with that procedure  214  or  214 ′ (see step  308  in  FIG. 3 ). 
         [0060]    The procedure latency monitor unit  204  may establish the measurement window  212  or  212 ′ pursuant steps  302  or  308  when the corresponding procedure  214  or  214 ′ has a delta time that exceeds a predetermined threshold  224  or  224 ′ (or different threshold) where the delta time is an amount of time that takes place between a start  218  or  218 ′ of the procedure  214  or  214 ′ and a stop  220  or  220 ′ of the procedure  214  or  214 ′. A more detailed description about when the measurement window  212  or  212 ′ may be established pursuant steps  302  or  308  is provided below with respect to  FIG. 4 . 
         [0061]    As can be seen, the eNodeB  102   a  (for example) described above provides a way of monitoring the procedures  214  and  214 ′ (e.g., radio network procedures, core network procedures) to trigger one or more admission control actions  228 . In particular, the eNodeB  102   a  measures the latency of procedures  214  and  214 ′ and when there is an increased procedure time then initiate admission control supervision. Alternatively, the eNodeB  102   a  measures the latency of procedures  214  and  214 ′ and the dropped UE sessions  230  and when there is an increased procedure time and an increased UE drop rates then initiate admission control supervision. 
         [0062]    For every procedure  214  (for example) used in the supervision of the admission control, there is a defined threshold t 0    224 . In addition, there is a delta time  216  that is measured for each procedure  214  (for example) which is the time between the start  218  of procedure  214  and the stop  220  of the procedure  214 . If no measurement is ongoing for the procedure  214  (for example), then a new measurement window  212  may be established and subsequent delta time  216  measurements started when a delta time breaches the t 0  threshold  224 , i.e. when the first procedure  214  exceeded its maximum delay time (see  FIG. 4 ). The measurement window  212  is active for the procedure  214  (for example) until N delta times  216  have been collected (i.e., N procedures  214  have started and completed). Once the measurement window  212  is closed, then a statistical evaluation of procedure delta times  216  may be performed so a determination may be made on whether or not any succeeding admission actions have to be performed, i.e. activate the admission control. 
         [0063]    Referring to  FIG. 4 , there is illustrated a latency measurement example where for procedure  214  (for example) there is a new measurement window  212  created when a delta time measurement  402  breaches the threshold t 0    224 . Then, after the creation of the new measurement window  212  several N delta times  216  are collected such that the mean delta time  222  may be calculated (i.e., N procedures  214  have started and completed). In this example, N=12. Of course N may take any appropriate value as it is a design parameter. In particular, every procedure  214  and  214 ′ has a measurement window  212  and  212 ′ that is used to create a mean delta time  222  and  222 ′ based on N number of measured delta times  216  or  216 ′ for the respective procedure  214  and  214 ′. When all N delta times  216  and  216 ′ have been measured for the procedure  214  and  214 ′ in the measurement window  212  and  212 ′ then the procedure latency monitor unit  204  calculates the procedure latency mean time (tPLM)  222  and  222 ′ for the monitored procedure  214  and  214 ′. A mean value is used to avoid the adverse effects of any possible oscillating behavior of the function. 
         [0064]    The procedure latency monitor unit  204  may collect procedure latency measurements  216  and  216 ′ (delta times  216  and  216 ′) simultaneously for all monitored procedures  214  and  214 ′. Admission control may be triggered if at least one procedure  214  and  214 ′ has a mean delta time  222  and  222 ′ which exceeds its threshold  224  and  224 ′. A possible enhancement is to include a dependency between procedure delta times such as follows: 
         [0000]    
       
         
           
             
               
                 1 
                 N 
               
                
               
                 
                   ∑ 
                   
                     i 
                     = 
                     0 
                   
                   N 
                 
                  
                 
                   Δ 
                    
                   
                       
                   
                    
                   
                     t 
                     i 
                   
                 
               
             
             = 
             tPLM 
           
         
       
     
         [0000]    The formula above calculates a mean procedure time for all (N) measured procedures. In this case, the admission control is being triggered when all the mean time of all procedures exceeds the configured threshold for overload. 
         [0065]    In any case, when all N delta time  216  and  216 ′ measurements for a particular procedure  214  or  214 ′ have been collected, and the decision about whether or not an indication  226  shall be sent to the admission control mechanism  202  has been taken, then the measurement window  212  and  212 ′ shall be closed. A new measurement window  212  and  212 ′ will be started when the next delta time  216  and  216 ′ has breached the t o  threshold  224  and  224 ′ for that particular procedure  214  and  214 ′. 
         [0066]    Every monitored procedure  214  and  214 ′ has a configurable threshold  224  and  224 ′ at which the admission control mechanism  202  is triggered with a high load signal  226  (raiseHighLoad(procedure)  226 ). The actions  228  that may be performed by the admission control mechanism  202  upon receiving the high load signal  226  may include anyone or a combination of the following (for example):
       Block one or more new UEs trying to connect to the eNodeB level.   Release one or more UEs  108  already connected based on a priority class;   Block a new data radio bearer setup.   Release of one or more data radio bearers.   Reduce observability monitoring.   Etc.       
 
         [0073]    After a situation where the procedure latency monitor unit  204  has sent the high load signal  226  (raiseHighLoad(procedure)  226 ) for a corresponding procedure  214  and  214 ′. If the procedure latency monitor unit  204  has determined that the mean delta time  222  has been lowered below the t 0  threshold  224  and  224 ′ for that procedure  214  and  214 ′ after the evaluation of the next measurement window  212  and  212 ′, then any outstanding admission action for that procedure  214  and  214 ′ may be ceased by issuing the cease high load signal  234  (e.g., ceaseHighLoad (procedure)  234 ) towards the admission control mechanism  202 . 
         [0074]    Referring to  FIG. 5 , there is a flowchart illustrating the basic steps of an exemplary method  500  implemented by the procedure latency monitor unit  204  in accordance with an embodiment of the present invention. Beginning at step  502 , establish the measurement window  212  when the procedure  214  (e.g., procedure A) has a delta time  216  that exceeds the predetermined threshold  224 , where the delta time  216  is an amount of time that takes place between a start  218  of the procedure  214  and a stop  220  of the procedure  214 . At step  504 , set a number of N delta time measurements  216  for the procedure  214  that are to be completed during the measurement window  212 . At step  506 , wait for the procedure  214  to occur. At step  508 , when the procedure  214  occurs, calculate the delta time  216  which indicates an amount of time that takes place between the start  218  of the procedure  214  and the stop  220  of the procedure  214 . At step  510 , decrement by one the number of N delta time  216  measurements that need to be completed during the measurement window  212 . At step  512 , determine if completed all of the N delta time  216  measurements that were set to be completed during the measurement window  212  (e.g., determine if N=0). If the result of the determine step  512  is no, then return and perform the wait step  506 . If the result of the determine step  512  is yes, then at step  514  stop the delta time  216  measurement. At step  516 , calculate the mean delta time  222  which is an average of the measured delta times  216  for the procedure  214 . At step  518 , check if the mean delta time  222  exceeds the predetermined threshold  224  which is associated with the procedure  214 . If the result of the check step  518  is yes, then at step  520  send the high load signal  226  (raiseHighLoad(procedure)  226 ) associated with the procedure  214  to the admission control mechanism  202 . If the result of the check step  518  is no, then at step  524  determine if there is an outstanding high load signal  226  that was previously sent and is still pending with the admission control mechanism  202 . If the result of the determine step  524  is no then end at step  522 . If the result of the determine step  524  is yes, then at step  526  send the cease high load signal  234  (e.g., ceaseHighLoad (procedure)  234 ) associated with the procedure  214  to the admission control mechanism  202 . 
         [0075]    From the foregoing, it may be seen that the new measure technique described above aims to cover all internal resources, e.g., if an internal resource is starting to reach its engineered capacity then this should be indicated (or predicted) by the measurement of one or more procedures regardless of the internal resource type. In particular, the new measure technique introduces a way to steer the admission control mechanism  202  and to determine if the internal resource of the eNodeB  102   a  (for example) has reached its engineered capacity or not by measuring the latency of procedure(s)  214  and  214 ′ and if desired by monitoring the UE drop levels  230 . For example, in a high load scenario it may be monitored that the completion times for the procedure(s)  214  and  214 ′ are stretched and that abnormal UE drop levels  230  are increasing. An abnormal UE drop level  230  may be determined by monitoring UE Context drops or ERAB drops which occur when the eNodeB  102   a  (for example) or the core network performs a release of the UE  108 , or a release of the data radio bearer used by the UE  108  without being requested by the UE  108 . Both these drops will adversely impact the end user. 
         [0076]    The procedure latency monitor unit  204  may help accomplish this by implementing a method of measuring delta times  216  on procedures  214  and  214 ′ (stop-start times). Then, when the monitored means delta time  222  for one or several procedures  214  and  214 ′ has breached a certain threshold  224 , when at the same time UE drop level  230  has increased (if this option is used), a high load signal  226  is sent to the admission control mechanism  202  which may then perform subsequent admission control actions  228 . Thus, the procedure latency monitor unit  204  may identify when the eNodeB  102   a  (for example) is in a high load situation or is likely to reach a high load situation and give the admission control mechanism  202  an opportunity to reduce the affects of the high load situation or prevent the affects of the high load situation. 
         [0077]    The procedure latency monitor unit  204  is shown purely on eNodeB level, but it will also impact the core network&#39;s load as the signaling load between eNodeB and CN (e.g, MME/S-GW  104 ) will decrease. This is because the procedure latency measurements may include one or more procedures  214  and  214 ′ that are CN procedure times, which provide end-to-end measurements, e.g., CN to RAN measurements. In addition, the admission control mechanism  202  is distributed amongst the eNodeBs  102   a ,  102   b , and  102   c  (for example) in the network  100 , so the embodiments of the present invention may also spare CN internal resources at high load scenarios since the eNodeBs  102   a ,  102   b  and  102   c  may, for example, block UE connections that would imply load to the CN. 
         [0078]    The exemplary embodiments of the present invention have been described above with respect to a LTE wireless telecommunications network and eNodeBs. However, the embodiments may be practiced in any type of wireless telecommunication network where there is a node (e.g., eNodeB, eNB, base station controller, RNC) that manages a cell in which a radio service may be provided to a UE  108 . For example, the present invention may be practiced in GSM, WCDMA or CDMA wireless telecommunication networks. 
         [0079]    Although multiple embodiments have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it should be understood that the invention is not limited to the disclosed embodiments, but instead is also capable of numerous rearrangements, modifications and substitutions without departing from the present invention that as has been set forth and defined within the following claims.

Technology Classification (CPC): 7