WO2010039070A1

WO2010039070A1 - Telecommunications network

Info

Publication number: WO2010039070A1
Application number: PCT/SE2008/051109
Authority: WO
Inventors: Fredrik Persson; Paul Stjernholm; Magnus Hurd; Lotta Voigt
Original assignee: Telefonaktiebolaget L M Ericsson (Publ)
Priority date: 2008-10-01
Filing date: 2008-10-01
Publication date: 2010-04-08

Abstract

In a telecommunications network, licences are required to use a portion of a network element's resources. A method is provided whereby a network element can dynamically adapt the size of the licensed portion by receiving or releasing one or more licences, based on the amount of traffic the network element is handling. In one embodiment, the network element monitors the amount of traffic and compares it with a threshold relative to the limitation provided by the current licensed capacity. If further licenses are required, the network element may request them from a management node in which licences are pooled. If the licensed capacity is not fully utilized, one or more licences may be released.

Description

TELECOMMUNICATIONS NETWORK

The present invention relates to telecommunications networks, and in particular to a method and devices for dynamically managing resources in a telecommunications network.

BACKGROUND

Mobile telecommunications networks generally consist of a radio access network (RAN) connected to a core network (CN) to provide communication services to the consumer. The RAN may consist of network elements (NE) - such as radio base stations (RBS), radio network controllers (RNC), or base station controllers (BSC) - connected directly or indirectly to nodes in the CN.

The RBS provides local RF coverage, i.e. by means of one or more cells, and may carry the traffic offered in the local coverage area. The capacity of the RBS determines the amount of traffic the RBS is capable of carrying, where the capacity is restricted by the resources available in the RBS. The limiting RBS resources may be of different kind, e.g. the RBS RF output power or the digital processing capability in a NE. These physical resource limitations may further be translated into logical limitations e.g. in terms of number of simultaneous users, number of channel elements, or maximum bit rate, etc, the NE is capable of handling at any one time.

The hardware resource limitations, or the logical capacity limitations that may be derived from them, may further be divided into capacity quanta, in uplink and downlink, controlled by software licenses, in order to provide capacity options within the telecommunications network. That is, an operator of the telecommunications network may utilize the capacity defined by the licences obtained. For example, current telecommunications networks provide licensed capacity (LC) as part of their offerings, where licences are required for the NE to operate up to a certain limit of its hardware resources. The amount of licensed capacity (as defined by the licences obtained by the operator) determines where those limits are. However, this solution is based on a manual and static allocation of licensed capacity, where a license is individual per NE. SUMMARY OF INVENTION

According to a first embodiment of the present invention, there is provided a method in a network element for a telecommunications network, the network element having a finite amount of hardware resources providing a first, upper, limit on the capacity of the network element to handle traffic. The method comprises the steps of receiving one or more licences to use a portion of the hardware resources, the one or more licences defining a second limit on the capacity of the network element to handle traffic. The method is characterized by the further steps of: monitoring the amount of traffic handled by the network element; and on the basis of said monitored amount of traffic handled by said network element, dynamically adapting the size of said licensed portion by releasing one or more of the received licences or receiving one or more further licences.

Thus, according to the present invention, a method is provided whereby a network element can dynamically adapt the size of the licensed portion by receiving or releasing one or more licences, based on the amount of traffic the network element is handling. In one embodiment, the network element dynamically adapts the size of the licensed portion by releasing a licence and receiving a new licence of different size, i.e. replacing a licence with another.

In further embodiments, the network element monitors the amount of traffic and compares it with a threshold relative to the second limit provided by the current licensed capacity. If further licenses are required, the network element may request them from a management node in which licences are pooled. If the licensed capacity is not fully utilized, one or more licences may be released.

In another embodiment, the network element reports the amount of traffic in the network element to the management node, and the management node determines whether further licences are required, or if one or more unused licences can be retrieved from the network element.

Thus, according to a second aspect of the present invention, there is provided a method in a management node for a telecommunications network, the telecommunications network further comprising at least a network element, wherein the network element has a finite amount of hardware resources providing a first, upper, limit on the capacity of the network element to handle traffic. The method comprises the steps of: pooling licences for the telecommunications network in a licence pool; and sending to the network element one or more licences to use a portion of said hardware resources, said one or more licences defining a second limit on the capacity of the network element to handle traffic. The method is characterized by the further steps of: on the basis of an amount of traffic handled by said network element, dynamically adapting the size of said licensed portion by retrieving one or more of said sent licences from the network element or sending one or more further licences to the network element.

The present invention therefore provides methods, a network element and a management node which operate to provide efficient utilization of resources within a telecommunications network.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the following drawings, in which:

Figure 1 is a schematic illustration of a telecommunications network according to the present invention;

Figure 2 is a schematic diagram of a radio base station according to the present invention;

Figure 3 is a schematic diagram of a management node according to the present invention;

Figure 4 is a flow chart of a method according to one embodiment of the present invention; and

Figure 5 is a flow chart of a method according to another embodiment of the present invention. DETAILED DESCRIPTION

The term "licence" has been used herein to signify a program, code, or other entity, that allows the NE to use a portion of its hardware resources (e.g. output power, processing power, etc), or to supply logical capacity (e.g. number of concurrent users, bit rate, etc). A licence may relate to capacity portions of fixed size, in which case one or more licences may be used to license variable amounts of hardware resources or logical capacity, or of variable size, in which case a single licence may be used to license variable amounts of hardware resources or logical resources as required, or of any combination thereof. The term "licensed capacity" has been used to describe the amount of hardware resources or logical capacity that is licensed for use within an NE.

Figure 1 is a schematic illustration of a telecommunications network 10 according to the present invention.

The network 10 includes radio base stations 12a, 12b, which transmit data and control signals to mobile terminals (also known as user equipments) 14a-14d in the downlink, and receive data and control signals from the mobile terminals 14a-14d in the uplink, as will be familiar to those skilled in the art.

According to the illustrated embodiment, the network 10 further comprises a management node 16, which generally communicates with, and receives communications from, the radio base stations 12a, 12b as explained in greater detail below. In one embodiment, the management node 16 is part of a core network of the telecommunications network 10; however, the management node 16 may in principle be anywhere in the network.

Those skilled in the art will appreciate that, where they are not necessary for explanation of the operation of the present invention, various features have been omitted from the above description of the network 10 for purposes of conciseness and clarity. However, in addition to radio base stations, the invention is applicable to other network elements such as radio network controllers (RNCs), base station controllers (BSCs) and others. Thus, in these embodiments, the management node further communicates with and receives communications from RNCs and BSCs as necessary. Figure 2 is a schematic diagram of a radio base station 12 according to the present invention.

The radio base station 12 comprises antennas 20a-20n, with associated Tx/Rx circuitry 22a-22n. Of course, it will be appreciated that the invention is equally applicable to radio base stations with one or any number of antennas and one or any number of separate Tx/Rx circuitry. Moreover, the numbers of antennas and Tx/Rx circuitry may not be the same; for example, signals to and from the antennas may be multiplexed through a single Tx/Rx circuitry.

Signals from the Tx/Rx circuitry 22a-22n are input to a processing unit 24, which is connected to a memory 26. In this example of a UMTS system, the radio base station 12 further comprises IUB interface circuitry 28, for maintaining communications over the IUB interface (the interface between the radio base station and a RNC).

According to embodiments of the present invention, the radio base station 12 also comprises circuitry 30 for interfacing with the management node 16, i.e. for sending communications to the management node, and for receiving communications from the management node.

The radio base station 12 is one example of a network element in which the present invention may be performed. Other examples include, but are not limited to, radio network controllers (RNC), base station controllers (BSC) and routers, and may also be performed in network elements not part of the radio access network.

Figure 3 is a schematic diagram of a management node 16 according to embodiments of the present invention.

The management node 16 comprises a bus 40 to which are connected a processing unit 42, a memory 44, an input device 46 and an output device 48. Further, according to the present invention, the management node 16 comprises a communication interface 50 for sending communications to, and receiving communications from, network elements including radio base stations, RNCs, and BSCs, as detailed above.

As mentioned above, the available resources within a particular NE place an upper limit on the amount of traffic that the NE can handle. In addition to this upper limit, an operator of the telecommunications network in certain situations must acquire licences to use the resources, placing a second limit on the amount of traffic the NE can handle (which is called "licensed capacity"). The licences may relate directly to the traffic, e.g. the number of concurrent users, the number of concurrent user equipments, the number of radio bearers, the bit rate and/or the number of codes, or may relate directly to the NE hardware resources themselves, e.g. output power, bandwidth, the number of frequencies and/or baseband processing power.

In an embodiment, the management node 16 operates to pool all the licences acquired by the operator, which may then be applied to any of the number of NEs which the operator uses. The licences may be stored locally in the management node 16 (e.g. in the memory 44), or remotely in a separate server or device (not illustrated). Further the licences may be partitioned according to different types of NE, or groups of NEs. For example, one portion of the licence pool may be for radio base stations, and another portion for RNCs, and so on.

According to the invention, licences are dynamically allocated to NEs according to the amount of traffic they are handling at any one time. If an operator is approaching its licensed capacity in an NE, i.e. the maximum amount of traffic the NE is capable of handling according to the licences allocated to it, the NE may receive one or more further licences, for example from the management node. Likewise if, in an NE the operator is handling an amount of traffic that is well below its licensed capacity, it may release one or more of its allocated licences, for example to the management node. In a further embodiment, an NE may release one of its allocated licences and replace it with a received licence which relates to a different amount of licensed capacity. In this way, an operator can most efficiently manage a pool of licences, such that capacity can be distributed to the NEs that need it the most.

Figure 4 is a flow chart of a method according to one embodiment of the present invention, performed in a network element such as a radio base station, a RNC, a BSC, or the like.

The method starts in step 100. In step 102, the NE monitors the amount of traffic it is currently handling. "Traffic" in this instance can mean any of, for example, the number of concurrent users, the number of concurrent user equipments, the number of radio bearers, the bit rate, the number of codes, the bandwidth, and/or the number of frequencies.

In step 104, the NE compares this amount of traffic with an upper threshold. The upper threshold is defined relative to the current licensed capacity of the NE (referred to as the "second limit" above), and in general is therefore equal to the licensed capacity, or less than the licensed capacity. In an embodiment, the upper threshold is set below and substantially close to the licensed capacity such that, if the upper threshold is exceeded, the licensed capacity is close to being fully utilized.

If the traffic is greater than the upper threshold, the NE requests one or more further licences in step 106, for example from the management node. This request may or may not be granted by the management node, depending on the number of licences that are available in the licence pool. If there are unused licences in the licence pool and the request is granted, the NE receives one or more further licences and the licensed capacity is therefore increased. If there are no unused licences in the licence pool, no further licences are sent and the licensed capacity remains the same. In one embodiment, there may be a lower limit on the amount of licences in the licence pool. If the amount of licences falls below the lower limit, a notification is sent to the operator indicating that the licence pool is short of licences. The method then repeats from step 102.

If the traffic is less than the upper threshold, the method proceeds to step 108, where the NE compares the traffic with a lower threshold. The lower threshold is set below the upper threshold, and allows unused licences to be released. If the traffic is less than the lower threshold, one or more licences are released in step 110, for example to the management node 16. That is, the licensed capacity is reduced. The management node 16 may then return the released licence(s) to the licence pool. The method then repeats from step 102.

If, in step 108, the traffic is greater than the lower threshold (i.e. if it is between the upper and lower thresholds), then no licences are released or requested, and the method repeats from step 102.

Once the licensed capacity has been changed by either receiving or releasing one or more licences, the upper and lower thresholds are adjusted accordingly. That is, if the licensed capacity is increased, the thresholds are also increased; if the licensed capacity is reduced, the thresholds are also reduced. For example, the thresholds may be changed by the same amount as the licensed capacity, or by the same proportion as the licensed capacity.

If the licensed capacity is particularly low, the lower threshold may reach zero, in which case steps 108 and 1 10 are effectively removed from the method, as the traffic cannot fall below the lower threshold. Similarly, the upper threshold cannot be set higher than the physical limitation provided by the hardware resources of the NE (defined as the "upper limit" above). That is, where an NE is only capable of handling 500 users at one time operating at maximum capacity, it will do no good to request extra licences. Therefore, the upper threshold may be limited by the hardware resources of the NE. Alternatively, the method may include a further step of checking to see if the physical limitations of the NE have been reached and, if so, not requesting further licences.

Figure 5 is a flow chart showing a method according to another embodiment of the present invention, performed in the management node 16.

The method begins in step 200. In step 202, the management node receives a report from a NE, indicating an amount of traffic the NE is handling. "Traffic" in this instance can mean any of, for example, the number of concurrent users, the number of concurrent user equipments, the number of radio bearers, the bit rate, the number of codes, the RF power, the bandwidth, and/or the number of frequencies.

In step 204, the management node compares this amount of traffic with an upper threshold, as described previously with respect to Figure 4. If the traffic is greater than the upper threshold, the method proceeds to step 206, where it is determined if there are licences available in the licence pool. If there are licences in the licence pool, one or more further licences are sent to the NE (step 208) and its licensed capacity is therefore increased. If there are not sufficient licences in the licence pool, no further licences are sent and the licensed capacity remains the same. In both cases, the method then repeats from step 202.

If the traffic is less than the upper threshold, the method proceeds to step 210, where the management node compares the traffic with a lower threshold, as described previously with respect to Figure 4. If the traffic is less than the lower threshold, one or more licences are retrieved from the NE in step 212, and its licensed capacity is reduced. The retrieval may be effected by requesting that the NE sends one or more licences back to the management node, or by actively taking the licences from the NE. The management node 16 may then return the released licence(s) to the licence pool. The method then repeats from step 202.

If the traffic is greater than the lower threshold (i.e. if it is between the upper and lower thresholds), then no licences are sent or retrieved, and the method repeats from step 202.

Again, once the licensed capacity has been changed by either sending or retrieving one or more licences, the upper and lower thresholds are adjusted accordingly. That is, if the licensed capacity is increased, the thresholds are also increased; if the licensed capacity is reduced, the thresholds are also reduced.

As previously mentioned, if the licensed capacity is particularly low, the lower threshold may reach zero, in which case steps 210 and 212 are effectively removed from the method, as the traffic cannot fall below the lower threshold. Alternatively, a minimum level may be set for each NE, below which the licensed capacity may not fall. Similarly, the upper threshold cannot be set higher than the physical limitation provided by the hardware resources of the NE. Therefore, the upper threshold may be limited by the hardware resources of the NE. Alternatively, the method may include a further step of checking to see if the physical limitations of the NE have been reached and, if so, not requesting further licences. Alternatively, the NE may check itself to see if its physical limitations have been reached and, if so, may not send a report to the management node at all, or may report this fact to the management node.

Thus, according to the present invention, an NE monitors the amount of traffic it is handling. Based on this monitored amount of traffic, the NE can request further licences or release existing licences to dynamically adapt its licensed capacity. Alternatively, the NE may report the monitored amount of traffic to a management node, which itself determines whether further licences are required in the NE, or whether one or more licences may be released.

According to a further aspect of the present invention, each NE under the operator's control sends a periodic status message to the management node. If the management node fails to receive one or more of these status messages from a particular NE, it assumes that NE has developed a fault and is no longer making use of its licensed capacity. In this instance, one or more, or all, of the licences that are allocated to that NE may be retrieved and returned to the licence pool.

For example, when a status message is received from the NE, a timer may be initiated in the management node. The timer is initiated with a time within which a further status message is expected to be received. If the timer reaches zero, that NE may be determined to have developed a fault and its licences revoked accordingly.

This aspect of the present invention therefore provides a "heartbeat mechanism", whereby NEs periodically indicate to the management node that they are performing correctly. If a NE fails (i.e. if a status message is not received), its licences are re-used in the rest of the network thereby ensuring an efficient utilization of the operator's available resources. In a further embodiment, if the connection between the core network and the NE fails such that no user traffic can be transferred, the NE stops sending the status messages to the management node, such that its licences are released (for example, down to zero or down to the minimum level as noted above).

Similarly, according to a yet further aspect of the present invention, the management node may send a periodic status message to each NE. If the NE fails to receive one or more of these status messages from the management node, one or more, or all, of the licences that are allocated to that NE may be released. This embodiment covers a situation where the connection between the core network and the NE fails, but the NE does not immediately become aware of the failure through loss of user traffic. The connection may therefore be monitored through status messages between the NE and the management node.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. The word "comprising" does not exclude the presence of elements or steps other than those listed in a claim, "a" or "an" does not exclude a plurality, and a single processor or other unit may fulfil the functions of several units recited in the claims. Any reference signs in the claims shall not be construed so as to limit their scope.

Claims

1. A method in a network element for a telecommunications network, said network element having a finite amount of hardware resources providing a first, upper, limit on the capacity of the network element to handle traffic, said method comprising: receiving one or more licences to use a portion of said hardware resources, said one or more licences defining a second limit on the capacity of the network element to handle traffic; characterized by the further steps of: monitoring the amount of traffic handled by the network element; and on the basis of said monitored amount of traffic handled by said network element, dynamically adapting the size of said licensed portion by releasing one or more of the received licences or receiving one or more further licences.

2. A method as claimed in claim 1 , further comprising: comparing said amount of traffic with one or more thresholds relative to said second limit; and on the basis of said comparison, dynamically adapting the size of said licensed portion.

3. A method as claimed in claim 2, wherein said one or more thresholds comprise an upper threshold, said dynamically adapting step comprising: if said amount of traffic is greater than said upper threshold, requesting one or more licences.

4. A method as claimed in claim 3, wherein said upper threshold is equal to or less than said second limit.

5. A method as claimed in any one of claims 2-4, wherein said one or more thresholds further comprise a lower threshold, said dynamically adapting step comprising: if said amount of traffic is less than said lower threshold, releasing one or more licences.

6. A method as claimed in claim 5 when dependent on claim 3 or 4, wherein said lower threshold is less than said upper threshold.

7. A method as claimed in any one of the preceding claims, the telecommunications network further comprising a management node in which licences for the telecommunications network are pooled, said dynamically adapting step further comprising: releasing one or more licences to the management node, or receiving one or more further licences from the management node.

8. A method as claimed in claim 7, further comprising: reporting said monitored amount of traffic to the management node.

9. A method as claimed in claim 7, further comprising: periodically receiving a first status message from the management node; and if the network element fails to receive one or more first status messages from the management node, discarding one or more of said received licences.

10. A method as claimed in claim 7, further comprising: periodically sending a second status message to the management node; and if a connection between the network element and a core network fails, not sending further second status messages to the management node.

11. A method as claimed in any one of the preceding claims, wherein said hardware resources include one or more of the following: number of users, number of user equipments, number of radio bearers, bit rate, number of codes, output power and baseband processing power.

12. A method as claimed in any one of the preceding claims, wherein said hardware resources include one or more of the following: bandwidth and number of frequencies.

13. A method as claimed in any one of the preceding claims, wherein said dynamically adapting the size of said licensed portion comprises releasing one or more of the received licences and receiving one or more further licences.

14. A network element, for use in a telecommunications network, said network element being adapted to perform the method according to any one of the preceding claims.

15. A network element as claimed in claim 14, wherein said network element is a radio basestation.

16. A network element as claimed in claim 14, wherein said network element is a radio network controller (RNC).

17. A method in a management node for a telecommunications network, said telecommunications network further comprising at least a network element, said network element having a finite amount of hardware resources providing a first, upper, limit on the capacity of the network element to handle traffic, said method comprising: pooling licences for the telecommunications network in a licence pool; and sending to the network element one or more licences to use a portion of said hardware resources, said one or more licences defining a second limit on the capacity of the network element to handle traffic; characterized by the further steps of: on the basis of an amount of traffic handled by said network element, dynamically adapting the size of said licensed portion by retrieving one or more of said sent licences from the network element or sending one or more further licences to the network element.

18. A method as claimed in claim 17, further comprising: receiving a report of the amount of traffic being handled by the network element; comparing said amount of traffic with one or more thresholds relative to said second limit; and on the basis of said comparison, dynamically adapting the size of said licensed portion.

19. A method as claimed in claim 18, wherein said one or more thresholds includes an upper threshold, said dynamically adapting step comprising: if said amount of traffic is greater than said upper threshold, sending one or more licences to the network element.

20. A method as claimed in claim 19, wherein said upper threshold is equal to or less than said second limit.

21. A method as claimed in any one of claims 18-20, wherein said one or more thresholds includes a lower threshold, said dynamically adapting step comprising: if said amount of traffic is less than said lower threshold, retrieving one or more licences from the network element.

22. A method as claimed in claim 21 when dependent on claim 19 or 20, wherein said lower threshold is less than said upper threshold.

23. A method as claimed in claim 17, further comprising: receiving a request from the network element for one or more licences; and sending one or more licences to the network element.

24. A method as claimed in claim 17, further comprising: periodically receiving a status message from the network element; and if the management node fails to receive one or more status messages from the network, reallocating licences for said licensed portion to the licence pool.

25. A method as claimed in any one of claims 17-24, wherein said dynamically adapting the size of said licensed portion comprises retrieving one or more of said sent licences from the network element and sending one or more further licences to the network element.

26. A management node, for use in a telecommunications network, said management node being adapted to perform the method according to any one of claims 17-25.