FR2863427A1 - ATM type physical connection database constructing method for e.g. computing network, involves constructing database of physical connections from pair of router interfaces in order to establish entire architecture of network - Google Patents

Abstract

The method involves determining connections of switches or cross connects (12A-12C) of low level layers by interrogating database of connections of switches or cross connects of low level layers of a data transmission network. A database of physical connections of the data transmission network is constructed from a pair of router interfaces in order to establish an entire architecture of the network.

Description

2863427 1

  Field of the Invention The present invention relates to the field of information transmission networks and more particularly to a method of constructing a database of physical connections of these networks.

  PRIOR ART Information transmission networks such as telecommunications and / or computer networks are increasingly complex and contain often heterogeneous equipment. Also, to build a database of connections and to ensure a supervision of these networks, it is necessary to know their global architecture. That is why, today, the management of a large-scale information transmission network uses specialized software such as OPENoverViewTM or OPNMSTM, ensuring as complete a supervision and description as possible of this architecture. However, the information found is essentially related to the IP layers of the network and not to those reporting physical links, for example.

  However, a good knowledge of a complex network of information transmission also supposes that of the lowest layers, and in particular of the first two layers of the OSI model, the physical layer and the link layer.

  There is therefore today a need for a data structure describing all the physical connections of an information transmission network, this structure of course also incorporating other pieces of information, such as bandwidth. , access port addresses, etc. In addition, this structure must be able to constantly evolve with the information transmission network of which it is the exact representation.

  OBJECT AND DEFINITION OF THE INVENTION The present invention therefore proposes to solve these problems with a method of constructing a database of the physical connections of an information transmission network, making it possible to have end visibility. at the end of the connections between the different interfaces of the routers forming this network.

  Thus, the invention relates to a method for constructing a database of the physical connections of an information transmission network comprising high layers interconnecting different routers interfaces and low layers interconnecting different interfaces. equipment, characterized in that the method comprises the following steps: interrogating the characteristics of the interfaces of the routers of the high layers of said network, determining for each interface of each router which is not directly connected to another router, the characteristics of the interface of the adjacent equipment connected to it, by interrogating at least one database of low layer equipment connections of said network, -building a database of the high layers comprising for each interface of each router, the characteristics of this interface as well as those of the interface of the low layer equipment its or router connected to it, -interrogate said database of high layers to determine among all the interfaces of all routers, pairs of routers interfaces corresponding to the router interfaces connected to each other directly or indirectly through a or more intermediate equipment, 2863427 3 -determining the connections of low-lying equipment by interrogating the database of low-lying equipment connections of said network, -building the database of the physical connections of said network, from said pairs router interfaces to establish a global architecture of said information transmission network.

  This method makes it possible to have a global view of the information transmission network from a database integrating all the physical connections between all the equipment and routers forming this network.

  The at least one low layer network connection database of the network comprises characteristics of the interfaces of said equipment corresponding to logical connection parameters which are chosen from the following parameters: interface type of the equipment, state of this interface , the type of physical link crossed, the bandwidth of the physical link crossed, and the names of the routers connected to the equipment.

  According to one particularity of the invention, the at least one base layer equipment connection database of the network comprises an ATM type database comprising logical connection parameters chosen from the following parameters: type of interfaces, band pass-through, virtual circuit number, virtual path number, constant bit rate for a CBR traffic contract, available bit rate for an ABR traffic contract, unspecified bit rate for a UBR traffic contract, variable bit rate for a VBR traffic contract, and name of the router connected to the low layer equipment.

  According to another particularity of the invention, the at least one base layer equipment connection database of the network comprises an SDH type database comprising logical connection parameters chosen from the following parameters: ## EQU1 ## interfaces, bandwidth, throughput, and characteristics of an existing SDH virtual container between low layer devices, and the name of the router connected to the low layer equipment.

  For an interface of a given router, when there is a match between the name of that given router and the name of the router connected to the adjacent equipment connected to that interface, and the characteristics of the interface of that adjacent equipment correspond to those of the given router, then there is connection between the interface of said router and the interface of the adjacent equipment.

  The interface of the given router is considered to be directly connected to another router if no adjacent equipment is found in the at least one low layer network connection database of the network.

  Advantageously, the database of the high layers comprises for each of the routers the following data: name of the router, type and eigenfeatures including sub-network of the high layers of each of its interfaces as well as the characteristics of the low-lying equipment or the router connected to it.

  The router interface pairs are determined by comparing the high layer subnetworks of the router interfaces with one another so that two interfaces of the two neighboring routers with the same IP subnet define a pair of routers.

  Advantageously, an update of the database of the physical connections of the information transmission network is performed by periodically interrogating the interfaces of the routers of the high layers of said network, which are compared then the data coming from the interrogation of the interfaces of the routers with the corresponding data recorded in the database of the high layers, which one still applies on the results resulting from this comparison of the predetermined logical rules to validate or not the data from said interrogation, and that finally the database of the upper layers is updated with said data thus validated in order to update the database of the physical connections of said information transmission network.

  Preferably, the database of the physical connections of said network can be visualized by a graphical interface.

Brief description of the drawings

  The features and advantages of the present invention will become more apparent from the following description, given by way of non-limiting indication, with reference to the appended drawings in which: FIG. 1 is a schematic view of an example of a data transmission network; implementing the method of the invention, - Figure 2 is a flowchart illustrating the different steps of construction of the database describing the architecture of a network of the type of Figure 1, Figure 3 illustrates a connection between two routers, - figure 4 shows the different records of the database corresponding to the connection of figure 3, and - figure 5 shows other records of the database corresponding to modifications of the connection of the figure. 3.

  DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT FIG. 1 schematically shows a partial example of an architecture of an information transmission network 1 comprising a network of high layers 5 such as IP having routers 14 to 22 and a network. ATM-type low layer network 10 having partially or fully interconnected switches or stirrers 12A, 12B, 12C. The ATM Layer Network Switches are connected to some routers of the IP Layer Network.

  In addition, the information transmission network 1 comprises an access network 11 comprising access devices connected by Ethernet, FastEthernet or other type of links to the network 5 of the IP layers. The access devices may include work stations 24, a collection station 26, a supervisory or management station 28 of the network 1, etc. Indeed, according to this example, the management station 28 is connected to the router 14 which is connected to a switch 12A. The switch 12A is in turn connected to a second switch 12B providing a link with a second router 16.

  This management station 28 can be used for the execution of a computer program designed to implement the method according to the invention.

  This part of the network implements the following network layers: ATM, IP, Ethernet, FastEthernet. But, of course, all network layers can be taken into account by the present invention, for example, without being limiting: IP, ATM, POS, SDH, WDM, Ethernet, FastEthernet, GigaEthernet, etc. The management station 28 of the network comprises, for example, an HP Open View type software application for monitoring and controlling the IP network and which communicates with the different routers forming this network by a specific protocol known as SNMP (Simple Network Management Protocol) that sends and receives PDUs (Protocol Data Unit) asynchronously. This protocol allows you to configure these routers, manage security and access to data, detect and analyze network anomalies, and monitor its performance.

  According to the invention, and as shown in the flowchart of FIG. 2, it is proposed to make a database including all the physical links between the routers and the various equipment of this network. In the remainder of the description, the word equipment designates any connection unit other than a router. Thus, an equipment may for example designate a switch, an asynchronous stirrer or multiplexer of the ATM type or synchronous type PDH or SDH.

  Thus, the information transmission network 1 comprises high layers (for example IP) and low layers interconnecting different interfaces of routers 14 to 22 and equipment 12A to 12C.

  In step E1, the characteristics of the routers interfaces of the upper layers of the network are interrogated, for example by SNMP. These features may include the name of the router, the description of the interface, and the type of interfaces.

  Thus each interface can be defined by a link card, a port, a sub-interface, a bandwidth, a mask, and the name of the remote router. Indeed, the name of the remote router can be determined from the description field of the interface based on the coding of this field. This can be in the form of a comma-separated string starting with "to" and ending with the name of the remote router.

  In step E2, for each interface of each router that is not directly connected to another router, the characteristics of the interface of the adjacent equipment connected to it are determined by interrogating at least one database. of lower layer equipment connections of the information transmission network.

  The database or databases of lower layer equipment connections of the network are databases known per se, including data that has been manually retrieved or by network layer-specific mechanisms from low layer equipment.

  These data comprise characteristics of the interfaces of the equipment of the lower layers corresponding to logical connection parameters which can be chosen from the following parameters: type of interface of the equipment, state of this interface, type of physical link crossed, bandwidth physical link traversed, and names of routers connected to the devices.

  The low layer equipment database of the network may be of the ATM type including logical connection parameters selected from the following parameters: type of interfaces, bandwidth (Bw), virtual circuit number (VC), path number virtual rate (VP), constant bit rate for a CBR traffic contract, available bit rate for an ABR traffic contract, unspecified bit rate for a UBR traffic contract, variable bit rate for a VBR traffic contract, and name of the router connected to the low layer equipment.

  Furthermore, the database of low layer equipment of the network may be of the SDH type comprising the following parameters: type of interfaces, bandwidth (Bw), bit rate and characteristics of an existing SDH virtual container between the layer equipment low, and name of the router connected to the low-level equipment.

  Thus, for an interface of a given router, when there is correspondence between the name of said given router and the name of the router connected to the adjacent equipment connected to this interface, and that the characteristics of the interface of said adjacent equipment correspond to those of the given router, then there is connection between the interface of said router and the interface of the adjacent equipment.

  In other words, for each router having an interface of the ATM type, (respectively SDH), we search the ATM database, (respectively SDH) if there is an ATM equipment (respectively SDH) connected to this router. The interfaces of the ATM equipment 2863427 9 (respectively SDH) are interrogated in order to compare the logical connection parameters of the interface of this router with those of the interface of the ATM equipment (respectively SDH). When the logical connection parameters of the router interface are identical to those of the interface of the ATM equipment (respectively SDH) and when there is correspondence with the name of the connected router, then the ATM equipment (respectively SDH) is the equipment adjacent to the router interface.

  For example, if the VP and / or VC of the router interface is identical to the VP and / or VC of an ATM switch and if there is correspondence with the name of the connected router then the ATM switch is the equipment adjacent to the router interface.

  Furthermore, the router interface is considered to be directly connected to another router if no ATM or SDH type adjacent equipment is found in any of the respective low layer equipment connection databases of the network.

  Similarly, when the router's interface is Ethernet or GE then this router is considered directly connected to another router.

  In step E3, a database of the high layers (for example an IP database) comprising for each interface of each router, the characteristics of said interface as well as those of the interface of the equipment of the router are constructed. layers or router connected to it.

  The upper layer database may include for each router the following data: router name, type and eigenfeatures (including sub-network of high layers, ie, masks and addresses of high layers) each of its interfaces as well as the characteristics of the low-level equipment or router connected to it.

  In particular, these data can be classified into primary and secondary data.

  Thus, the main data may include the name of the router that SNMP queries, the interface type and the interface's own characteristics, and the characteristics of the adjacent equipment including the name of the adjacent ATM equipment, VP, VC, (or name of the adjacent SDH device, Virtual Container), link card, port, and subinterface.

  In addition, all other data in the upper layer database may be considered secondary.

  In step E4, this database of high layers is interrogated to determine, among all the interfaces of all the routers, pairs of router interfaces corresponding to the router interfaces connected to each other directly or indirectly through one or more equipment. intermediate.

  These pairs of routers interfaces are determined by comparing between them the sub-network of the high layers (IP subnetwork), that is to say the masks and addresses of the high layers (IP), the interfaces of the routers of so that two interfaces of these two neighboring routers having the same subnet of the high layers (IP) define a pair of routers.

  In other words, each interface of each of the routers of the database of the high layers is connected either directly (in ATM, SDH or Ethernet etc), or indirectly (via an ATM or SDH network) to an interface of another router. the database of the high layers, said adjacent or adjacent router. Thus, two neighboring routers form a pair of routers constituting the ends of a connection.

  Thus, a communication can be characterized by two connections. A connection of the communication is defined in a forward direction and another connection in a return direction. In the connection database, a router is thus registered as a "source router" for a one-way connection and as a "destination router" for connection in the opposite direction. So, any interface of a connected mode router is the end of a connection. Thus, to be able to associate the interfaces of the routers in pairs, all the interfaces of all the routers of the base of the high layers are interrogated. On the one hand, when the searched router corresponds to the name of the remote router described at the source router then this router is said "destination router" of the source router. On the other hand, when two interfaces of the two neighboring routers have the same subnet of the high layers then these two interfaces are the ends of the connection.

  In step E5, the low-level equipment connections are determined by querying the database of low-level equipment connections of the information transmission network.

  Finally, in step E6, the database of the physical connections of the information transmission network can be constructed from the pairs of router interfaces obtained by means of the database of the high layers, in order to establish a overall architecture of this information transmission network.

  It will be noted that the database of the physical connections of the information transmission network can be visualized by a graphical interface.

  The method according to the invention also makes it possible to update the database of the physical connections of the information transmission network.

  This is achieved by periodically interrogating the interfaces of the routers of the high layers of this network, and then comparing the data from the interrogation of the interfaces of the routers with the corresponding data recorded in the database of the high layers.

  It is possible to apply on the results resulting from this comparison predetermined logic rules to validate or not the new data coming from the interrogation.

  On the one hand, if, after this comparison, the main data are identical, then the secondary data are compared.

  If the secondary data is the same, then there is no need to save the data from the query.

  On the other hand, if the secondary data are different, then the database can be updated by recording the last data from the query.

  On the other hand, if the main data is different, then the primary and secondary data are replaced in the database by the new data.

  It should be noted that more elaborate rules, for example of the cognitive type, in the context of the operation of an expert system could also be envisaged, particularly in the case of particularly complex networks.

  Thus, the database of the high layers can be updated with the data validated according to the logical rules above.

  Of course, the updating of the database of the high layers, according to the flow chart of FIG. 2, makes it possible to update the database of the physical connections of the information transmission network.

  More particularly, when the two types of data are different, it is then displayed for a network administrator a comparative table of these data before and after the update so as to allow him or her to retain or not this data according to the 2863427 13 knowledge of the network. If it decides to keep the new data, then the database is actually updated.

  This data includes the description of the connections between the interfaces of the routers.

  A direct connection can be described as follows: Connection (i) = "name of the source router (i)", "type of interface", "bandwidth", "name of the destination router (I)".

  An indirect connection, for example via an ATM network, can be described as follows: Connection (i) = "name of the source router (i)", "bandwidth", "name of the ATM switch", "VP", "VC" ", ...," ATM (I) switch name "," VP (k) "," VC (k) "," bandwidth (k) "," destination router name (I) ". It should be noted that the characteristics of the intermediate ATM switches of the ATM transport network are obtained from the ATM database.

  An indirect connection, for example via an SDH network, can be described as follows: Connection (i) = "name of the source router (i)", "bandwitdth", "name of the SDH equipment", "Virtual Container",. .., "device name (l) SDH", "Virtual Container", "bandwitdth (k)", "destination router name (l)". Likewise, the characteristics of the SDH intermediate SDH transport network equipment are obtained from the SDH database.

  FIG. 3 illustrates an example of an indirect connection, via an ATM network, which can commonly be encountered in a network of the type of FIG. 1 and which concerns a connection between two routers A and B designated by the references 30 and 36 respectively .

  The method according to the flowchart of FIG. 2 makes it possible to discover a first ATM switch (reference 32) connected to the router 30 by a first physical link 34 and a second ATM switch 30 (reference 38) connected to the router 36 by a second physical link 40.

  Moreover, a last link 42 interconnecting the first and second switches 32 and 38 is known from the ATM database.

  FIG. 4 illustrates a typical example of a file of the physical connection data base, displayed on the network management station and corresponding to the connection of FIG. 3.

  The first line 50 of this file corresponds to the link going from the router A to the router B and the second line 52 of the file corresponds to the reverse link going from the router B to the router A. For each equipment of the connection: source equipment, intermediate equipment and remote equipment, we note the nature of the interfaces (int) input and / or output, the bandwidth (Bw) expressed in megabits per second (Mb), the virtual circuit (VC) and the virtual path (VP) between the equipment. It will be noted that, depending on the direction of the link, the source equipment for a link becomes the remote device for the reverse link and vice versa.

  Figure 5 illustrates this same file during an update performed after the router A has been disconnected from the network for any reason (eg failure or manual manipulation). It is assumed, of course, that this disconnection information has not come to the knowledge of the network administrator. The previously recorded data and the data coming from the update following the interrogation of the equipment of the computer network are displayed simultaneously on a display screen of the network management station 28 for information of the network administrator who will then find that the connection line 50 from Router A to Router B is removed (leaving room for a white line 54) and that on the reverse connection line 52 from Router B to Router A, the remote equipment (then router A ) no longer appears, the new connection line 56 being limited to a connection between the source equipment 2863427 (Router B) and the intermediate equipment (in this case the switches 32 and 38).

  The administrator can then accept or not the proposed network change. If it accepts it by validating the update, for example after noting to the persons concerned the effective removal of the router A network, then the file will be modified and the database will be made consistent with the new physical architecture network.

  It is easily understood that the aforementioned semi-automatic method applies to any physical modification that may occur on the network. Such a modification can occur at any time, according to a determined periodicity of network scanning.

  Thus, with the method of the invention, it is possible to continuously monitor a highly scalable network, in the sense that a speaker can change network parameters without notifying the network administrator. This is particularly the case for experimental networks in which integration tests of new services, therefore card validations and various interfaces are performed constantly. Such networks must also adapt to the arrival of new equipment. In addition, the method of the invention makes it possible to have a global view of the network from a single database integrating all the logical connections between all the low and high layer equipment, all the crossed low layers are listed, and whose content can be viewed in 2D or 3D via a graphical interface.

Claims (3)

16 CLAIMS   A method of constructing a database of physical connections of an information transmission network (1) having high layers interconnecting different router interfaces (14, 16, 18, 20, 22) and low layers interconnecting different equipment interfaces (12A, 12B, 12C), characterized in that the method comprises the following steps: interrogating the characteristics of the interfaces of the routers of the high layers of said network, -determining for each interface of each router which is not directly connected to another router, the characteristics of the interface of the adjacent equipment connected to it, by interrogating at least one database of connections of low-lying equipment of said network, -build a database of the high layers comprising for each interface of each router, the specific characteristics of said interface as well as those of the interface of the equipment of e low layers or the router connected to it, -interrogate said database of high layers to determine among all the interfaces of all routers, pairs of routers interfaces corresponding to the router interfaces connected to each other directly or indirectly to through one or more intermediate equipment, -determining the connections of low-lying equipment by interrogating the database of low-lying equipment connections of said network, -building the database of the physical connections of said network, from said pairs router interfaces to establish a global architecture of said information transmission network.   Method according to claim 1, characterized in that the at least one low-level network connection database of the network comprises characteristics of the interfaces of said equipment corresponding to logical connection parameters which are chosen from the following parameters: type of interface of the equipment, state of this interface, type of physical link crossed, bandwidth of the physical link traversed, and names of the routers connected to the equipment.   3. Method according to any one of claims 1 and 2, characterized in that the at least one base layer equipment connection database of the network comprises an ATM-type database comprising logical connection parameters selected among the following parameters: type of interfaces, bandwidth (Bw), virtual circuit number (VC), virtual path number (VP), constant bit rate for a CBR traffic contract, available bit rate for an ABR traffic contract, debit not specified for a UBR traffic contract, variable bit rate for a VBR traffic contract, and name of the router connected to the low layer equipment.   4. Method according to any one of claims 1 and 2, characterized in that the at least one base layer equipment connection database of the network comprises an SDH type database comprising logical connection parameters selected among the following parameters: type of interfaces, bandwidth (Bw), bit rate and characteristics of an existing SDH virtual container between low layer equipment, and name of the router connected to the low layer equipment.   5. A method according to any one of claims 1 to 4, characterized in that, for an interface of a given router, when there is correspondence between the name of said given router and the name of the router connected to the router. adjacent equipment connected to this interface, and that the characteristics of the interface of said adjacent equipment correspond to those of the given router, then there is connection between the interface of said router and the interface of the adjacent equipment.   6. Method according to any one of claims 1 to 5, characterized in that the interface of the given router is considered to be directly connected to another router if no adjacent equipment is found in the at least one data base. low-level network equipment connections.   7. Method according to any one of claims 1 to 6, characterized in that the database of the upper layers comprises for each of the routers, the following data: name of the router, type and eigenfeatures including subnet IP of each its interfaces as well as the characteristics of the low-level equipment or router connected to it.   8. Method according to any one of claims 1 to 7, characterized in that said pairs of routers interfaces are determined by comparing between them the sub-networks of the high layers of the routers interfaces so that two interfaces of the two routers neighbors with the same high-level subnet define a pair of routers.   9. Method according to any one of claims 1 to 8, characterized in that an update of the database of physical connections of the information transmission network is achieved by the fact that one periodically interrogates the interfaces of the routers of the high layers of said network, which is then compared the data from the interrogation of the interfaces of the routers with the corresponding data recorded in the database of the high layers, that the the results obtained from this comparison also apply predetermined logic rules to validate or not the data coming from said interrogation, and that finally the database of the upper layers is updated with said data thus validated so as to update day the database of physical connections of said information transmission network.   10. Method according to any one of claims 1 to 9, characterized in that the database of the physical connections of said network is displayed by a graphical interface.