SE514589C2 - Management of networks - Google Patents

Abstract

The invention describes how telecommunication services can be handled in Access Networks (AN). A management concept is proposed that will enhance management by using a "loose coupling" between the defined telecommunication services and the transport network on which they are based. A "loose coupling" means here that Managed Objects in the service layer and in the transport layer are not that tightly coupled due to a separation of service, protocol and transport resources. This means that the service definitions will not be directly or indirectly logically contained in a physical port. Two embodiments of the invention are shown to demonstrate its use and advantages.

Description

U 20 25 30 35 514 589 2 band services are connected. The standardization work for these is in progress.

Until now, only an ETSI recommendation (ETR 257 1996-03 DTR / SPS-03040) and a preliminary ETSI standard (DE / SPS-03046-1) exist. However, new standards are constantly emerging.

Other ETSI standards define management interfaces for configuration services in an access network (AN). V5.1 and V5.2 are also standardized in this area, while VB5.1 and VB5.2 standardization work is in progress. However, none of these standards, nor any of the standards to which they refer, concern the question of how service definitions are linked to transport resources in the network element (NE). NE is used here as a common term that covers both AN and LE. The management interface for these transport resources is fairly well defined in an interim ETSI Standard (I-ETS 300 653).

Due to the lack of standardization of broadband interfaces (VB5.1 and VB5.2), we will only use V5.1 and V5.2 examples in this application. However, the principles described should also be valid for VB5.

REPORT FOR: THE INVENTION Today, the connection of telecommunication services is made in a not too simple and flexible way. There are solutions that do not provide the opportunity to evaluate entered service information or make measurements to detect obstacles to configuration services in the network. This means that even small changes in the service affect other parts of the service which in turn can affect additional parts and so on. This makes the system inflexible and complicated. 3 15 20 25 30 35 514 sas 3 'The part of the service configuration that will be described in this application relates to a method for managing services in TMN-based access networks which includes service configuration and mapping of managed objects and a method for configuring local exchange and the access network side of a service node interface (ie, for example, the V5 interface itself) in a telecommunication system and the mapping of related managed objects (MOs) to the various MOs representing the transport network. MO is defined here as a logical representation of a physical or logical resource.

The solutions proposed so far by ETSI are not as flexible as they could be. The unity relationship between different MOs in their latest proposal will work but has some major disadvantages. This will be described later, but briefly it means that most of the different V5 MOs that contain service definitions are too intimately connected to the transport network by being directly or indirectly logically enclosed in a physical port. Inclusion is in this case disadvantageous, because the service can not be moved from one port to another without deleting the service resources and re-creating them. This form of change is very useful to be able to make if e.g. a card in NE (Network Element) breaks or if the connection to an LE is broken, as reshaping an MO is not an easy task. When one MO is deleted, its association with other MOs is deleted. Re-creation of these associations often requires operations on the MOs to which the current MO is related.

Furthermore, the solution only reflects the immediate state of an access network (AN), ie. it is not clear how a service could be prepared. The need for a service is normally known a few days before it needs to be activated, ie. it will typically take a few days from the time the subscriber requests a new service until it is activated. If a service cannot be connected e.g. due to lack of internal bandwidth in AN, this will not be detected until the management system tries to activate the service. At this time, it may be expensive or impossible to correct the error without affecting the service promised to the customer.

In addition, some of the non-V5-specific parts of the information model are only useful for passive optical networks (PON).

The invention proposes a management concept that will improve the management by using a "loose" connection between the defined telecommunication services and the transport network on which they are based. A "loose connection" here means that a V5 MO is no longer so intimately connected due to a separation of transport, protocol and service resources, ie. V5 MOs that contain service definitions will not be too intimately connected to the transport network by not being directly or indirectly logically connected to a physical port. Instead, the associations between MO that belong to the service resources and MO that belong to the transport resources are realized by using pointers which, in contrast to inclusive kinship, can be changed during the lifetime of the current MO. By basing management on this concept, it is possible to reconfigure the transport network without affecting the connection of the telecommunication services used. On this concept, systems with the following properties can be built: - Separate containment hierarchies for the MO from the transport network, service and protocol fragments with only a loose connection between the MO that is not part of the same fragment.

- Regardless of the technology used in AN (eg copper, fiber or radio).

Enables the detection of service activation problems already when the requested service is entered into the management system (before the service is activated). This enables preparedness in the provision of services.

N U 20 25 30 35 514 589 5 - Can be realized by using objects that are already defined in standards.

In order to achieve all the above-mentioned properties simultaneously, the solution according to the invention, as mentioned, needs a separation of transport, protocol and service resources so that the LE protocol fragment and the AN protocol fragment can become the only connection between the service fragment and the transport fragment.

A "fragment" in this context can be defined as a grouping of a limited number of object class definitions. Each fragment handles a certain thing. The new idea here is the identification of these four fragments and the way in which these have been chosen to be bound together. Thus, we have taken a number of independent standards and found a new method of combining them in a flexible way to achieve the above and below mentioned advantages.

The implementation principle enables e.g. for a change of protocol between LE and AN in a simple way where LE and AN protocol fragments can be replaced with other MOs representing the new protocol. The only effect on MO in the service and transfer fragments is that the pointers to the protocol fragment MO may have changed. This means that the often time-consuming process of inventorying line cards in the network elements does not need to be repeated. Inventory is an activity performed by the user of management systems. It is performed by specifying which hardware (eg cables and line cards) is or will be installed in NE.

When a line card or connection breaks, the service that uses this resource often has to be moved to non-alert resources. The loose connection is advantageous regardless of whether the error affects the aggregated side (LE-AN interface) or the tributary side (the line to a single subscriber).

The advantage is greatest on the aggregate_side. 10 15 20 25 30 35 514 589 BRIEF DESCRIPTION OF THE DRAWINGS The features of the invention which are believed to be novel are set forth in the characterizing part of the appended claims. However, the invention itself, both in terms of organization and method of operation, together with further objects and advantages thereof, can best be understood by reference to the following description taken in conjunction with the accompanying drawings, in several figures in which: Figure 1 shows an example of a access network according to the prior art, - figure 2 shows a V5 interface at an access network according to the state of the art, - figure 3 shows a block diagram showing a unit relationship diagram for V5 management in accordance with an ETSI solution, - figure Figure 4 shows a block diagram showing a proposed solution for fragment relationship in an information model, Figure 5 shows possible layers in the information model, Figure 6 shows a block diagram showing a proposed unit relationship diagram for V5 management in access networks, Figure 7 shows an information model for a proposed embodiment of the invention showing a model of a PSTN service using V5.1, - figure 8 shows an information model for a proposed embodiment of the invention showing a model of a PSTN service using V5.2.

DESCRIPTION OF PREFERRED EMBODIMENTS Two embodiments of the invention will be shown in detail to illustrate its use and advantages.

Figure 1 shows that an AN can either be a single access network node (ANN) or it can be a subnet consisting of a number of internally connected ANNs as shown in the figure. The internal structure of an AN does not concern the invention and this will therefore treat the AN as a "black box". Using this principle, the AN shown in Figure 1 will look like in Figure 2.

Figure 3 shows previous technology in accordance with an ETSI solution (ETSI TM2 / WG4, 1996-08: "Draft of DE / TM 2209.3: Transmission (Element) Fragment") where a unit relationship diagram for V5 handling in optical networks is shown. In the figure, the diamonds are used to represent the intimate logical inclusions and the absence of a diamond indicates a pointer from one unit to another, ie. a more "loose" enclosure / coupling. The dots indicate multiplicity, e.g. For example, an access network element can contain several V5 interfaces, but a pPItp can only contain one V5Ttp (no dot used). For a better understanding of the figure, it is appropriate to define the most important abbreviations: pPI - Plesiochronous Physical Interface, Ttp - Trail - Termination Point, onu - Optical Network Unit, olt - Optical Line Terminal. For a more detailed list of abbreviations, see the last paragraph of this chapter.

With this approach, most V5 MOs (managed objects) are very intimately connected to the transport network by being directly or indirectly enclosed in a pPITtp that represents a physical port. An important disadvantage is therefore that a service cannot be moved from one port to another without deleting the service definition and creating it again.

Figure 4 shows in a general way and in accordance with the solution of the invention the relationship between the different fragments in an information model. The transport, protocol and service resources are in accordance with the idea of the invention here separated and the lines between the fragments symbolize associations between the MO contained therein. It is worth noting that the protocol fragments on each page may be the only connection between the service fragment and the transport fragment. The link between the service management warehouse MO and the network management warehouse MO is in some respects different depending on whether concentration is placed on the interface between AN and LE. Therefore, the invention will be shown in two embodiments which will illustrate the fact that the advantages and features mentioned in the disclosure may be implemented in the same solution.

Common to the two solutions is that they are divided into three main layers: service layers, road layers and transmission media layers.

Road and transmission media layers can be subdivided if appropriate. The two solutions that will be described are based on 2048 kbit / s PDH and are used for four layers. The path layer is divided into two as shown in Figure 5. The invention is not limited to 2048 kbit / s PDH. Instead, it is possible for systems with a second bit rates and hierarchies. In addition, other divisions of layers are of course also part of the concept of the invention.

The service fragment in Figure 4 contains the MO that belongs to the service layer shown in Figure 5, while the transport fragment contains the MO that belongs to the road layer and the transmission media layer_ The MOs in LE and the AN protocol fragments belong to the service layer or road layer.

Figure 6 shows in accordance with the invention, with a unit relationship diagram, that it is possible to construct an containment hierarchy without the intimate hardware binding of the objects in the protocol fragments as can be seen in the ETSI proposal in Figure 3 and still make it possible to achieve the - veneered MOs follow the standards. In embodiments of the invention, it will be shown that four instances of the warehouse network domain (one for each warehouse in Figure 5) are used for the information model representing the system. By using this principle with four layers in Figure 6, the connection between v5Ttp (enclosed in the Electricity storage network domain) and the physical nTP (enclosed in the physical storage network domain) will be loose. as shown by the lack of diamonds between them. This means that the linking between them takes place only with pointers and that there is no intimate logical containment relationship.

The physical nTTP in Figure 6 functionally corresponds to the ETSI-pPITtp in Figure 3 which has an intimate inclusion-based relationship to its v5Ttp as shown by the diamond between them.

Note that Figure 4 and Figure 6 do not show all relationships as the purpose is only to show the containment hierarchy.

A storage network domain (LND) is used as a convenient way to separate the network according to the transmission layer. As shown in Figure 5, we use four layers in this example. There will be an LND for each of these layers.

Figures 7 and 8 will show two information models showing two different embodiments of the invention to clarify that the idea is possible to implement. The first (Figure 7) shows a simplified version of a possible solution for a model with a PSTN service called V5.1 and which implements "loose connection" in a system with fixed time slot allocation.

AN with a fixed time slot allocation for services is the most used today. This principle is easy to implement in NE (Network Element), but takes up more bandwidth on the communication link than necessary (given that the average subscriber uses his phone / connection only a few minutes every day). V5.l only supports this schedule with fixed time slot allocation.

The way in which the associations are drawn in the instance diagrams (Figure 7 and Figure 8) deserves an explanation. The arrows show which path the associations can be traced through the model. When a solid line is used, the association can be read from an attribute in MO. A dashed line is used to show informative associations that are not directly visible through the attributes in the model. The enclosure is not shown in Figures 7 and 8 as this would make these more difficult to read without giving the reader that much more information.

Figure 7 clearly shows different fragments and separation of transport, protocol and service resources into four blocks. We also see with the horizontal dotted lines how different layers (service, EO, Electricity and the physical layer) are divided.

The example used here is a scenario for defining a PSTN (POTS) service. Four steps are required to obtain the instance diagram shown in Figure 7. l. Define / inventory the transport network resources. 2. Add a protocol to one or more tracks in the network. 3. Define the service by creating two service NTTPs, a service track, a tandem connection and connecting an (inactive) subnet connection. 4. Activate the service by creating the relevant ports and channels in the protocol fragment and connecting their associations with the rest of the model.

Step 4 can be performed immediately after step 3. In many cases, however, step 4 will be planned to be performed a few days after step 3. If the service for some reason can not be connected, this will in most cases be detected already in step 3, which gives the operator extra time to fix the problem before step 4 is scheduled to be performed.

Figure 8 shows, in the same way as Figure 7, a possible information model (IM) where the separation between the fragments is visible.

Here in an embodiment with an IM solution of a PSTN service using V5.2 with dynamic time slot allocation (concentration).

When the time slot allocation is changed from static to dynamic, the number of subscribers that can be served by a certain bandwidth between LE and AN can be significantly increased. A concentration factor of 10 is not uncommon, which means that a connection with dynamic time slot allocation can serve the same number of subscribers as ten connections with the same bandwidth that use static allocation.

Handling of dynamic time slot allocation places extra demands on AN. In practice, this means that AN must be able to handle ordinary switching functionally. Dynamic time slot allocation is not supported by V5.1, ie. V5.2 required.

Furthermore, this figure also indicates that the only connection between the service fragment and the transport fragment is via the protocol fragment on each side, which means that e.g. in a case where the protocol is changed (eg from corporate property protocols such as CAS / ESM to standardized ones such as V5.1 or V5.2) the MOs in the LE and AN protocol fragments can be replaced with other MOs as represents the new protocol. The only impact on MO in the service fragment and the transport fragment is that the pointers to the protocol fragments MOs may need to be changed.

The scenario for defining a PSTN service is repeated with some modifications. Three steps are required to obtain the instance diagram shown in Figure É. 1. Define / inventory the transport network (TN) resources. 2. Add a protocol to one or more tracks in the network. 3. Define and activate the service by creating two service NTTPs and one service track. 4. Activate the service by creating the relevant ports and channels in the protocol fragment and connecting their associations with the rest of the model. 10 15 20 25 30 514 589 The difference between this example and the previous one is not visible until the service is defined in step 3. Some of the associations that are valid when the time slot allocation is static cannot be used here.

It is important to note that the figures only show a possible solution which comprises a plurality of MOs, the solution thus showing the fact that the above-mentioned advantageous properties can be realized in the same solution.

While the invention has been described in connection with a preferred embodiment, it is apparent to those skilled in the art that the present invention may be modified in a number of ways and may take many other embodiments than those specifically set forth and described above, for example, while the examples shown in the document focus on V5 as this is one of a few protocols with a standard TMN interface, the described principles can also be used in other environments where protocol-dependent telecommunication services are connected in a network such as in a "video on demand" service in an ATM or ADSL networks.

Thus, the appended claims are intended to cover all modifications of the invention which fall within the spirit and scope of the invention.

As the terminology in this technology uses many abbreviations, the following list is attached: ADSL Asynchronous Digital Subscriber Line AN Access Network ANN Access Network Node ATM Asynchronous Transfer Mode CTP Connection Termination Point 10 Ü 20 E0 El ETSI IM ISDN-BA LC LE Mov NCTP NE NML NTTP oLT oNU PON Pows PPI PSTN sML sNc SNI 514 589 U 13 1- 64 kbit / s 2048 kbit / s European Telecommunications Standards Institute Information Model Integrated Digital Services Network-Basic Access Link Connection Local Exchange Managed Object Network Connection Termination Point Network Element Network Management Layer Network Trail Termination Point Optical Line Terminal Optical Network Unit Passive Optical Network Plain Ordinary Telephone Service Plesynchronous Physical Interface Public Switched Telephone Network Service Management Layer SubNetwork Connection Service Node Interface 10 TMN TN TP TS TTP UNI UPBC VA 514 589 Telecommunications Management Network Transport Network Termination point Time Slot (64kbit / s) Trail Termination Point User Network Interface User Port Bearer Channel Virtual Access

Claims (6)

10 U 20 25 30 35 514 589 H PATENT REQUIREMENTS A method for managing services in TMN-based access networks comprising service configuration and mapping of managed objects (MO), characterized by a separation of service, transport and protocol resources by implementing said resources in a service warehouse, a road warehouse and a transmission media layer, - identifying service, transport and protocol fragments, said service fragment comprising the MO belonging to the service layer, said transport fragment comprising the MO belonging to the road layer and the transmission media layer, said protocol fragment comprising the MO as belong to the service layer and the road layer, - to use separate containment hierarchies for the MOs in each respective fragment, - to associate the MO in the service fragment with the MO in the transport fragments by using a loose link between the defined telecommunications services and the transport network on which these are based. A method for managing services in TMN-based access networks according to claim 1, characterized in that associations via the MO in the protocol fragment are the only connection between the MO from the service fragment and the MO from the transport fragment. Method for managing services in TMN-based access networks according to claim 1 or 2, characterized in that said service configuration relates to configuration of a V5 or a VB5 interface and that said mapping of the MO refers to mapping of V5 or VB5-related MO to the MO representing the transport network. 10 15 20 25 30 35 514 589 l 6 A method for configuring the local exchange (LE) and access networks (AN) side of a service node interface in a telecommunication system using service, transport and protocol resources, the resources being represented by managed objects (MO), characterized in that the configuration of said part of the service node interface entails, - an identification of a service, a transport, an LE protocol and an AN protocol fragment, - a separation of said resources in said fragment, - an association of MO: ni the service fragment with the MO: ni the transport fragment by using a loose connection between defined telecommunication services and the transport network on which these are based, said loose connection being logically used only via said LE protocol fragment and via said AN protocol fragment. An information model representing the local exchange (LE) and access network (AN) side of a service node interface in a telecommunication system using service, transport and protocol resources, the information model comprising managed objects (MO) and associations between said MO characterized in that said information model further comprises, t - an identification of a service, a transport, an LE protocol and an AN protocol fragment, - a separation of said resources in said fragment. An information model representing the local exchange (LE) and access network (AN) side of a service node interface in a telecommunication system according to claim 5, characterized in that said information model further comprises: - an association of the MO in the service fragment with MO: in the transport fragment by using a loose connection between defined telecommunication services and the transport network on which these are based, said loose connection being logically used via said LE protocol fragment and via said AN protocol fragment.