Network management device and method for setting up a logical link in a synchronous digital transmission system

0001The invention relates to a network control means for establishing a logical connection in a digital synchronous Message transmission network according to the preamble of claim 1 and a method according to the preamble of claim 9.

0002Existing digital synchronous message-transmission networks such as SDH or SONET networks (SDH: Synchronous Digital Hierarchy, SONET: synchronous optical network) are static networks, ie logical Connections in the transmission network are of a Management system more or less set up permanently.

0003In the article ,, Network Planning and Management ", O. Gonález Soto et al, Electrical Communication, Alcatel, issue 4/1993, pages 366-377 it is described that an unexpected degree of flexibility for covering Demand change in SDH networks by providing a certain Oversupply is achieved. can through online management processes this oversupply in the short term, ie for the period of a few days be used up to several months.

0004is carried out to set up logical connections in the SDH network then as part of a network planning due to predictions of Requirement for some years. For network planning is the SDH network into subnets divided to be optimized separately. Optimising takes place in two management layers by means of a routing process, which estimates the cost for each way and taken into account.

0005After completion of the network planning of the online management process generates in the event that the capacity limit established connection is achieved, on the lower layer management a provisioning request. If the capacitance of the lower administrative layer is depleted, is a Provisioning request to the process for establishment of the upper path directed management layer, where it automatically or by the Workers can be performed. Such Provisioning requests are on the subnets and the individual Network operators limited. In addition, the adaptation of this type only Bottlenecks in this period are taken into account of several days. Frequent short-term bottlenecks can only be lasting Provision of additional transmission capacity will be met, the but then over long periods of time to the times of shortages remains unused.

0006Object of the invention is therefore to provide a power control device and a Method for setting up logical connections in a digital specify the synchronous data transmission network, which better allow use of existing transmission capacity.

0007The object is achieved with regard to the network controller by the features of claim 1 and as to the method by Features of claim 9. Advantageous embodiments are the dependent claims.

0008The invention is particularly for the construction of leased lines, so-called leased lines, advantageous and useful. In addition to the better utilization existing transmission capacity has the invention further Benefits that communications networks flexibly to currently prevailing demand can be adapted and that Communications networks to use and better at User needs are matched.

0009Claim 7 describes a particularly advantageous development of Invention which makes it possible that desired by a customer Connection parameters are specified as priority, bandwidth, desired date that the requested connection, desired duration of the provision of the requested connection and / or desired safety and quality features of the requested connection. Thereby the operators to open up digital synchronous communications networks or new -teilnetze Business by automatic means limited time Leased line (so-called leased lines) at a certain time with predetermined characteristics is made possible.

0010In the following, an embodiment of the invention with reference to the Figures 1 and 2 explained in which:<dl tsize="7" compact="compact"><dt>figure 1</dt><dd>a schematic representation of the management structure of a digital synchronous data transmission network with a Network control device according to the invention and</dd><dt>figure 2</dt><dd>a flow chart of the inventive method.</dd></dl>

0011A basic idea of ​​the invention is a to provide network control device that is capable of individual receiving connection requests, for such Connection request a path through the select communication network and the construction of for causing the requested connection over the selected path.

0012In the figure, 1 is the hierarchical structure of the management of a digital synchronous data transmission network schematically shown. A communications network consists of various Network elements such as cross-connect systems and DXC Add / Drop multiplexers ADM, with each other via the physical Compounds such as fiber optic or coaxial cable to a network are intermeshed.

0013For a number of similar network elements of a sub-network exists in each case a Network element management device SH. This is for the control and Monitoring network element-specific functions, such as the By switching a connection, responsible, and for network element-specific messages and alarms. The Network element management facilities of a subnet are connected to a regional management device, the so-called Regional Manager RM connected. This controls the connection setup, the network planning and optimization in the subnet. The Regional Manager of subnets with a superior management device, the so-called Country Manager CM connected. This parent Management means CM manages for example the Communications network of a country or an operator.

0014According to the invention is a network control device NSE for building logical connections provided. The network controller is NSE connected to the Country Manager CM. It has access means for example in the form of an Internet interface INET through which a customer KD send a connection request to the network controller can. The connection request contains the order, a logical establish connection within the communications network, for example, a leased line from Stuttgart to London. The Network control device then selects by a selection means a for the logical connection to appropriate path, for example by a processor with associated program memory, in which a one stored selection algorithm abarbeitendes selection program.

0015The selection of the path can be done in different ways: A Possibility is that the network control device via a Has memory in which data about the structure of Communications network are stored. can from this data the possible, that existing in the transmission network Paths are determined. Via the connection to the country manager CM can now inquire about the current utilization for each possible path will then make a selection of the most appropriate path based on the becomes. It is also possible, for each possible path under consideration the current load and, for example, the length of the path a determining cost parameters. The selection is then made such that the cost route is chosen. Advantageously the data on the structure of the communications network in the memory in The form of a routing table stored.

0016Another possibility for the selection of the path is the Connection request in parameterized form, eg in the form Start and end point of the compound to the country manager forward, which then identifies possible paths and this as a result the network controller returns. From these possible paths then, for example, also on the basis of a cost parameter a done selecting the most appropriate path.

0017The network control device NSE has means for causing the Connection establishment of logical connection to be established over the selected path. This includes an interface device associated with the Country Manager connectable. This may be for example, a specified for management purposes in SDH interface Q act (ITU-T G.773 March 1993). Via this interface instructions to the Country Manager sent the logical connection to be over establish the selected path. Advantageously, the Network control device NSE additional interfaces to Country managers of other operators or countries. Thereby, a cross-border connection of various including Operators made possible by more than the additional interfaces Information about the structure and utilization of adjacent Communications networks can be queried.

0018According to an advantageous development of the invention are the Access information suited next to the connection request also to receive Authentikationsinformationen from Customers eröglichen, clearly establish the identity of the client and to to verify. These are in the network controller means for checking the Authentikationsinformationen provided. This ensures, that only eligible customers a connection request to the Network control device addressed. In addition, an automatic Settlement of costs incurred for the connection charges on a corresponding account allows. The authentication can for example by means of a smart card of the customer, on the Authentikationsinformationen and keys are stored.

0019In Figure 2 is a flowchart of the method according to the invention shown. The following steps are performed:<dl tsize="11" compact="compact"><dt>Step S1:</dt><dd>A connection request for a logical connection is from a customer, preferably over an Internet hotline receive.</dd><dt>Step S2:</dt><dd>There are all possible paths in the Communications network determines that the for building logical link could be envisaged and that the availability Capacity feature. From the possible paths of a will for the connection selected. Preferably happens this by for any path cost parameters in Depending on the length, the number zwischengeschalter Network elements and the utilization of einzelen path segments is determined and the most cost-effective path is selected.</dd><dt>Step S3:</dt><dd>The structure of the logical connection through the selected Path is caused by the path parameters with the Instructions establish the logical connection to the Country Manager will be forwarded. Of the Connection itself is then of the Management devices using so-called "Managed Objects "carried out as in the article by MP Bosse et al., "Management of SDH network elements: an application of Information Modeling "in Electrical Communication Alcatel, issue 4/1993, pages 329-338 indicated.</dd></dl>

0020You can move between step S1 and step S2 is advantageously in a further step S1A done an authentication of the customer. To transmits the encrypted customer Authentikationsinformationen the Network control device, which then Authentikationsinformationen checked to determine the identity and authorization of customers and verified. The authentication can be done using a carried out by the customer chip card, on which the Authentikationsinformationen and a key stored.

0021A particularly advantageous development of the invention permits desired by a client connection parameters are specified, as priority, bandwidth, desired date that the requested connection, desired duration of the provision of the requested connection and / or desired safety and Quality characteristics of the requested connection. These Connection parameters when the network controller Selecting an appropriate path considered. Is a suitable path found, the network controller sends a confirmation signal back to the customer, which of the actual connection parameters connection to be made contains.

0022The network controller includes a memory in which Connection requirements of different customers to the execution of each connection request is stored. This is advantageous, since the path search other currently open, ie not yet completed, Connection requests are taken into account, for example, a Wish connection for overlapping period. following are some examples of connection parameters, as the customer is a could indicate: <ul><li>High priority:<ul><li>instant connection or at the latest in X seconds or minutes</li><li>Connection establishment for a period of hours from the time X the confirmation of</li></ul></li><li>Medium priority:<ul><li>Connection in one day during the Rush hour (9:00 to 17:00)</li><li>Connection during a predetermined period off-peak time. The period is 12 announced hours in advance.</li></ul></li><li>Low priority:<ul><li>Connection sometime during off-peak time (at night).</li></ul>The network controller has output means, for example, a web interface to the customer, by means of an acknowledgment signal with the actual connection parameters is sent to the customer. This acknowledgment signal, the customer can then, for example, the see actual time of connecting. Advantageous is the cost parameters as a function of the actual Connection parameters calculated. This cost parameters, besides the used selection of a path also for charging for the customer will. This makes it possible that the network control means also Fee calculation assumes. Operators of digital synchronous Communications networks or member networks will open up new Business by automatic means limited time Leased line (so-called leased lines) at a certain time with given bandwidth and security features is made possible. In addition, the flexibility of the network to the customer is increased, since this now can order temporary connections, what with recent Leased lines was not possible.</li></ul>