DE10012864A1 - Data transmission in communications network - forming first network address with first format under consideration of second network address with second format, and transmitting data to communication arrangement using first network address - Google Patents

Abstract

The method involves transmitting data to at least one communication arrangement (NE) of a communications network (KN), in which the associated communication arrangements are addressed with a first network addresses (A) comprising a first format (F1). A first network address (AOSI) having the first format is formed under consideration of a second network address (AIP) having a second format (F2). The data are transmitted to the communication arrangement using the first network address.

Description

For a targeted transmission of information between communica connected by communication networks tion devices is a clear addressing of the comm communication facilities required. Usually for this every communication device in every communication onsnetz to which it is assigned, a unique network address assigned. Such a combination of a certain comm Communication network associated communication devices in the professional world also as' subnet ',' domain ',' region ',' Au tonomous system (AS) ',' Local Area Network (LAN) 'or, if applicable also known as 'Wide Area Network (WAN)'.

The number of communications assigned to a subnet directions are usually limited. Hence find yourself a large number of subnets in contemporary network structures, which are interconnected by gateway devices are. Gateway devices are special communications facilities that have at least two subnets at the same time are assigned and in each one for the respective subnet have a unique network address. You will also become 'gateway' or 'router'.

Usually come in different subnets different regulations for the transmission of information for use. These regulations are also called 'protocols' called. You will e.g. B. to control at the Informati onsubmission used addressing, about transmission, mediation, authentication or priority process used. According to the ISO (In ternational Organization for Standardization) OSI (Open Systems Interconnection) reference model are protocols  one each of several protocol layers arranges. A total of seven layers are provided, whereby in the lower four layers are communicated networks is regulated. Layer 1 - also called 'Physical Lay he 'called - is the point-to-point transmission between two line end devices via physical conductors such as B. copper cable, optical fiber or air assigned, Layer 2 - also called 'Control Layer' - the treatment transmission errors in layer 1; layer 3 - also called 'network layer' - the route in one mesh network of intermediaries; and layer 4 - also called 'transport layer' - the handling of errors in the layers below as well as controlling the targeted transmission of information between two communicati onsendeinrichtung. The OSI are for each of the layers Protocols proposed, which are also referred to as' OSI protocol be called 'le'.

In each communication assigned to a communication network onseinrichtung is at least a layer 1 protocol as well Usually at least one layer 2 protocol is provided, the services of the layer 1 protocol from the layer 2 Protocol can be used. Communication facilities, in only protocols up to layer 2 are preferred depending on their function, for example Called 'bridges', 'hub', 'layer 2 switch' or 'converter', Communication designed as gateway devices facilities with protocols up to layer 4, for example 'Gateway', 'Layer 3/4 switch' or 'Router'. In each of these Communication devices are therefore a multitude of pros tokollen provided according to the OSI reference model are layered. Such a layering of logs is also known as a 'protocol stack'.

Traditionally, communication networks have mainly become the loka len networking - also called 'intranetworking' - by Kommu nication facilities used. Here, the  respective manufacturers usually proprietary, d. H. sub network-specific addressing schemes introduced, which are also in contemporary network structures are still frequently used. Examples of subnets with subnet-specific addressing schemes are Ethernet, Token-Ring, SNA or ATM.

Thus, when networking the subnets - also 'Internet word called king '- a cross-subnet addressing scheme required the use of different subnets specific addressing schemes is taken into account. On The Layer 3 protocol of the Internet provides an example of this, the so-called Internet Protocol IP. This will include 32 bits addresses set. The value of a specific IP address is usually written in the notation xxx.xxx.xxx.xxx, 0 ⇐ xxx ⇐ 255, where each xxx has the value of 8 neighboring bits of the 32-bit address.

When internetworking using the IP protocol, this is not an option a map in each of the subnets along a route Ping between the IP addresses and those in the respective subnet subnet-specific network addresses required, since single from the communication facilities of the subnets subnet-specific network addresses are recognized - e.g. B. only the 48 bits of an Ethernet module Ethernet addresses, but not the IP addresses. The format of the Ethernet addresses is in the 802.3 standard of the IEEE (In stitute of Electrical and Electronics Engineers).

In Tanenbaum, "Computer Networks", ^3rd Edition, Prentice-Hall, Inc., 1996, ISBN 0-13-394248-1, pp 420-423, two methods are disclosed for mapping the addresses. One solution is to provide a configuration file somewhere in the subnet in which the addresses are mapped to one another. However, this solution is very error-prone and maintenance-intensive, especially in a large subnet.

Another solution - 'Address Resolution Protocol ARP' ge called - is that from one transmitter to all communica cations facilities of a subnet broadcast by an after is sent in the search for the owner of a IP address is asked. This message is from the owner zer answered with a message in which his subnetzspe specific address is included. With the help of this The shared address is then followed by information about averaging by the broadcaster. This procedure is only in Applicable to subnets that provide broadcast messages. To that is the ARP protocol in each of the communication devices provision.

It is an object of the invention to transmit Information required to determine network addresses improve. The task is characterized by the features of the patent spell 1 solved.

The essential aspect of the invention is a method ren for the transmission of information to at least one com Communication device in a communication network in which the assigned communication devices with a first Format addressing network addresses are addressed at the considering one of the first format below different second format having the second network address a first network address having the first format is formed and the information using the first network address are transmitted to the communication device.

Some essential advantages of the invention are mentioned below:

• - Regardless of the format requirements of a subnet, to which a communication device is assigned Cross-subnetwork second network addresses of a uniform Chen format are used.
• - The determination of the first network addresses is consequently automatic education simplified.  
• - In particular, the use of a mapping table or an address resolution protocol ARP to determine the first network addresses not required.

After a further development of the method according to the invention becomes the first network address taking into account the second Network address calculated - claim 2. According to a Vari the calculation is carried out on the basis of the method according to the invention locally, d. H. without interactions with the communication facility tion of the communication network - claim 3. Thus the formation of the first network address is very efficient because advantageously no interactions with the communication directions of a subnet are required.

According to an embodiment of the method according to the invention it is provided that the first network address is the second network address resse - preferably unchanged - contains - Claim 4 or Claim 5. The first network address is thus formed and vice versa the second network address is particularly efficient, especially if there is no encryption of the second network address is taken.

According to a development of the method according to the invention, the first network address is formed by adding a prefix to the second network address - claim 6. According to an embodiment of the method according to the invention, it is provided that when addressing in the communication network, the requirements of a connection less network protocol CLNP are met trained OSI protocol, the first network address is formed by assigning a hexadecimal value 0 × 31 for a prefix designed as an Authority And Format Identifier AFI and inserting the second network address (A _IP ) into a domain specific part DSP according to the following claim 7. By using the private address characterize the AFI 0x31 address conflicts between the - preferably automatically formed - first network addresses and the remaining network addresses provided in the address space of the CLNP protocol are avoided.

According to a variant of the method according to the invention second format according to the rules of an internet Protocol trained - claim 8. In accordance with proven ver drive to avoid address conflicts formed internet Addresses are thus combined with the private addresses characteristic AFI 0x31 of the protocol CLNP first network address sen formed, which is advantageously inherently free from address conflict are within the communication network. In addition, it does not apply at this point the use of a complex process for Mapping of network addresses such as B. configuration files or special protocols such as B. ARP or ES-IS.

Further advantageous embodiments of the invention result itself from the subordinate or subordinate claims.

The invention is described below with reference to exemplary embodiments play, which are shown in several figures, he closer purifies.

Show:

Fig. 1 is a block diagram of a schematic depicting a lung Kommunikationseinrich invention tung,

Fig. 2 is a network address format according to the OSI CLNP protocol,

3 shows a plurality of interconnected protocol stacks.,

Fig. 4 shows a network of communication networks with two he inventive, as gateway devices formed from communication devices.

In Fig. 1, a communication device KE according to the invention is shown as an example, which has at least a first protocol stack PS ₁ (F ₁ ) for connection to a communication network KN ₁ (F ₁ ) with network addresses A _{OSI of} a first format F ₁ . Between the first protocol stack PS ₁ and the communication network KN ₁ , the first format F ₁ having network addresses A _OSI (F ₁ ) are transmitted when information is transmitted. In addition, at least one second protocol stack PS ₂ (F ₂ ) is provided for connection to a fictitious communication network KN ₂ (F ₂ ) with network addresses A _{IP of} a second format F ₂ . The protocol stacks PS are connected to each other by an adapter PI. With the first protocol stack PS ₁ , the adapter PI exchanges network addresses A _OSI having the first format F ₁ . Compared to the second protocol stack PS _2, the adapter PI acts as the fictitious communication network KN ₂ (F ₂ ), ie, inter alia the network addresses A _IP having the second format F ₂ are exchanged. Thus, the adapter PI converts the network addresses A between the two formats F ₁ and F ₂ . To configure the network address A _{OSI of} the communication device KE in the communication network KN ₁ (F ₁ ), only the network address A _{IP1 having} the second format F ₂ and assigned to the second protocol stack PS _{2 is} defined and communicated.

In FIG. 2 a network address format is OSI CLNP protocol illustrated in accordance with the. Such a network address has a prefix P, preferably in the form of an authority and format identifier AFI with a value of 0x31, followed by a domain-specific part DSP, into which network addresses A _IP (F ₂ ) having the second format F ₂ according to the invention for forming the first format F ₁ having network addresses A _{OSI are} inserted. This is also called reachable address prefix RAP.

In Fig. 3, exemplary embodiments of two interconnected with an adapter PI protocol stack PS are shown. Here, one of the protocol stacks includes PS OSI protocols, e.g. B. the layered OSI protocols CLNP and LLC1. The other protocol stack PS are IP protocols arranged side by side and ICMP assigned. The adapter PI is arranged between the protocols IP and CLNP. One in a z. B. to an Ethernet connected gateway GW possibly provided further protocol stack PS has, for example, the stacked protocols IP and EI. Within its respective layer, the protocol IP is assigned a protocol ICMP and the protocol EI a protocol ARP. All protocol stacks PS access the physical line with the help of a layer 1 protocol LI, ie the assignment of the communication devices to communication networks takes place on a logically abstract level (e.g. by means of different protocol stacks PS) and not on a physical level (e.g. E.g. by different assemblies).

In FIG. 4 is an example of a composite of six communica tion networks CN _i, 1 ⇐ i ⇐ 6, where in the Kommu CN nikationsnetz ₁ network addresses A of the first format F ₁ and in the communication networks CN ₂ -KN ₆ of the second format F ₂ come into use. The second communication network KN ₂ is merely formed as a fictitious, virtual communication network KN, the information streams of which are tunneled through the first communication network KN ₁ , ie two protocols of the same layer are encapsulated with one another in such a way that the data of the first protocol is incorporated into the data packets of the second protocol are packaged. The following communication networks KN are connected to one another with the aid of communication devices KE formed as gateway devices GW: KN ₁ with KN ₃ , KN ₁ with KN ₄ , KN ₄ with KN ₅ , and KN ₅ with KN ₅ . In this case, a gateway device GW _{1 designed} according to the invention is provided between the communication networks KN ₁ and KN _{3 and} a gateway device GW _{2 designed} according to the invention is provided between the communication networks KN ₁ and KN ₄ . The network gateway devices GW each have at least two protocol stacks PS, which are connected to one another with the aid of an adapter PI.

The communication devices of the communication networks KN, for example, are assigned network addresses A _IP which are formed in accordance with the Internet protocol IP. The following address spaces are provided:

• - in communication network KN ₂ : 128. xxx.xxx.xxx,
• - in communication network KN ₃ : 128. 30. 30.xxx,
• - in communication network KN ₄ : 128. 10. 10.xxx,
• - in communication network KN ₅ : 128. 10. 4.xxx,
• - in communication network KN ₆ : 128. 10. 6.xxx.

In the communication network KN ₁ , subnet-specific addressing takes place, for example, with network addresses A _{OSI in} accordance with the OSI protocol CLNP, that is, network addresses A _OSI with a pre-fix P 0x31 (hexadecimal) = 49 (decimal) contain a do main specific part DSP, which can be freely assigned according to the prescribed format F ₁ . In addition, the communication network KN _{1 is assigned} a further communication device KE with a network address A _OSI = 35 110 254 255 91, ie this network address A _OSI does not contain a prefix P designed as an authority and format identifier AFI. The communication networks KN ₂ - KN ₆ are carried out the subnet-specific addressing z. B. with network addresses A _E according to the regulations that are used in an Ethernet.

The invention is based on the network scenario shown in Fig. 4 exemplified. It is this mationsübermittlung a infor between the communication network KN ₃ assigned communication device KE _A and the Kom munikationsnetz KN ₆ associated communication device KE _B considered. The communication device KE _A is assigned the IP network address A _IP = 128.30.30.5 and the communication device KE _B the IP network address A _IP = 128.10.6.2. In addition, each Ethernet module in the communication networks KN ₃ -KN _{6 is assigned} a globally unique, 48-bit Ethernet address A _E , which is burned onto it during manufacture.

The network gateway GW ₁ is assigned the network address A _IP = 128.10.99.2 for the fictitious communication network KN ₂ and the network address A _IP2 = 128.10.10.1 for the communication network KN ₄ ; the network gateway device GW ₂ is assigned the network address A _IP1 = 128.30.77.2 for the fictitious communication network KN ₂ and the network address A _IP2 = 128.30.30.1 for the communication network KN ₃ . From this, the network transition device GW _{1 is formed} by adding the prefix P, formed as an authority and format identifier AFI, with the value 0x31, the network address A _OSI = 49-12810992 of the network transfer device GW ₁ in the communication network KN ₁ - see also FIG. 2. In the same way, the network address A _OSI = 49-12830772 in the communication network KN _{2 is} formed in the network transition device GW ₂ . As a result of the conflict-free address allocation of the Internet network addresses A _IP , the two OSI network addresses A _{OSI formed are} also conflict-free. Even with the network address A _OSI = 35-11025425591 of the further communication device KE assigned to the communication network KN ₁ , there is no address conflict due to the different prefix P.

According to the invention, no entries of OSI network addresses A _{OSI are} required in the routing tables RT of the two gateway devices GW. Thus, proven routing tables RT can advantageously be used, in which only Internet network addresses A _{IP are} provided. For example, the following entries in the routing tables RT are provided for the above information transmission between the KE _A and KE _B communication devices:

in the GW ₁ gateway:

and in the gateway ₂ :

Information is transmitted from the KE _A communication device to the KE _B communication device as a sequence of several subnet-specific transmission processes in the following order: KN ₃ ⇒ KN ₁ ⇒ KN ₄ ⇒ KN ₅ ⇒ KN ₆ .

For the transmission of information in the subnets KN _x , 3 ⇐ x ⇐ 6, the Internet addresses A _IP are resolved into subnet-specific Ethernet addresses A _E. This is done e.g. B. with the help of the ARP protocol, which is described in the RFC 826 standard of the IETF (Internet Engineering Task Force).

For the transmission of information in the subnet KN ₁ - ie from the gateway GW ₂ to the gateway GW ₁ - according to the routing table RT ₂ as NEXT HOP, the gateway KE _{1 designed} as a gateway GW with the Internet address A _IP = 128.30 .77.2 determined. In the example, this is resolved into an OSI address A _OSI which, from the perspective of the Internet Protocol IP, represents a subnet-specific network address A.

An OSI address A _OSI can have up to 20 bytes. For this exemplary embodiment it is assumed that the OSI address comprises 5 bytes: 1 byte for an Authority And Format Identifier AFI and 4 bytes for a Domain Specific Part DSP. According to the OSI address A _OSI is formed taking account of the IP address A _IP , z. B. by inserting the IP address A _IP in the Domain Specific Part DSP and a hexadecimal value 0x31 (= decimal value 49) in the prefix P formed as Authority And For mat Identifier AFI. The OSI address A _OSI thus contains the IP address A _IP .

An IP address A _IP can be inserted into the Domain Specific Part DSP in various ways. There are particularly nice advantages if the OSI address A _{OSI contains} the IP address A _IP unchanged, since no conversion of the binary sequence is required. The following values result:

Alternatively, the decimal value of the IP address A _IP can be inserted unchanged, but the binary value of the IP address A _{IP can be} changed. This leads e.g. B. for the following values:

In a further variant, the decimal value of the IP address A _{IP can} also be expanded by inserting zeros in such a way that the original decimal representation of the IP address A _{IP can} be recovered in the receiver. The binary value of the IP address A _IP is also changed, and the following values result:

The calculation methods mentioned are only a few examples that embody the invention. Any other calculation methods can be used. The calculation of the OSI address A _OSI takes place locally in the gateway GW ₂ , ie in particular without using a mapping protocol, such as. B. the protocols ARP or ES-IS or somewhere else in the subnet KN ₁ - z. B. in another communication device KE - provided configuration file.

The information is now transmitted to the gateway GW ₁ using the network address A _OSI formed according to the invention. This may require further resolution of the OST address A _OSI in subnet-specific network addresses A from the perspective of the OSI protocol CLNP. A suitable procedure for this - called 'End System to Intermediate System ES-IS' - is described in ISO Standard 9542.

In the opposite direction, ie from the communication device KE _B to the communication device KE _A , the information is transmitted in the communication networks KN using the same methods, in particular using the same methods for mapping network addresses A.

In conclusion, it should be pointed out that the invention can be used in any type of communication network KN. For example, an application is provided in:

• - Wide area communication networks KN, such as. B. the Inter net - also called 'Wide Area Network' or 'WAN' -
• - local communication networks KN - also 'Local Area Net work 'or' LAN '- called,
• - Virtual communication networks KN, such as. B. a virtual Private network - also called 'VPN' - or e.g. B. the priority sub-network of a DiffServ network.

Claims (9)

1. Method for transmitting information to at least one communication device (KE) of a communication network (KN) in which the assigned communication devices (KE) are addressed with the first network addresses (A) having a first format (F ₁ ), with the following Steps:

• - taking into account a different from the first format (F ₁₎ second format (F ₂₎ having the second network address (A _IP) is formed a first format (F ₁₎ comprising, first network address (A _OSI),
• - The information is transmitted to the communication device (KE) using the first network address (A _OSI ).

2. The method according to claim 1, characterized in that the first network address (A _OSI ) is calculated taking into account the second network address (A _IP ). 3. The method according to claim 1, characterized, that the calculation is done locally. 4. The method according to any one of claims 1 to 3, characterized in that the first network address (A _OSI ) contains the second network address (A _IP ). 5. The method according to any one of the preceding claims, characterized in that the first network address (A _OSI ) contains the second network address (A _IP ) unchanged. 6. The method according to any one of the preceding claims, characterized in that the first network address (A _OSI ) is formed by adding a pre-fix (P) to the second network address (A _IP ). 7. The method as claimed in claim 6, characterized in that when addressing in the communication network (KN), the first network address (A _OSI ) is formed in accordance with the regulations of an OSI protocol (OSI) designed as a Connection Less Network Protocol (CLNP), by assigning a hexadecimal value 0x31 for a prefix (P) designed as an authorization and format identifier (AFI) and inserting the second network address (A _IP ) into a subsequent Domain Specific Part (DSP). 8. The method according to any one of the preceding claims, characterized in that the second format (F ₂ ) is designed in accordance with the requirements of an Internet protocol (IP). 9. Arrangement for performing a method according to one of the previous claims.