FI105737B - Data routing in a communication network - Google Patents

Description

105737

The present invention relates to data or data routing in a communication network. In particular, though not necessarily, the invention relates to a method and apparatus for collecting debit information relating to Internet use.

10 Typically, Information Service Providers (ISPs) provide their own information and interactive services to subscribers, and additionally provide subscribers with a gateway to the Internet and thereby to thousands of service providers around the world. Subscribers 15 also get access to the Internet and thousands of smaller ISPs directly through smaller local ISPs.

The Internet comprises a number of communication links and networks interconnected through "routers" 20. ISPs typically rent bandwidths on these links, networks, and routers from operators such as telecommunications operators and therefore need to offset their investments and make a ·· profit by passing on costs to their subscribers.

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Generally, large ISPs charge their subscribers on a time-consuming basis, e.g., based on connection time, when a financial relationship is established between the subscriber and the ISP. At the same time 30 ways smaller! local ISPs often base their service rates on subscribers' Internet usage times. Smaller ISPs either do not charge for connections to their own services, or if they do, they also require the user to enter into some form of financial contract.

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Internet users are identified on the Internet by the Internet Protocol (IP) using addresses reserved for users or service providers. When charging users, the number of packets sent and received, as well as the source and retrieval packets, are generally not taken into account. As mentioned above, fixed, time-based, or packet / byte billing mechanisms are used today. Mechanisms for circuit-switched 10 bandwidth allocation and billing are currently being designed.

Most circuit switched telecommunication systems eg conventional telephone networks, ATM networks etc.

15 are able to perform billing based on distance (local / long distance) and based on the fact that the connection is reserved and maintained for the duration of the call, although the data containing the traffic in progress may run irregularly on the link. However, the methods used for circuit switched telecommunication cannot be directly applied to packet switched telecommunication used on the Internet because there is no equivalent for "circuit" and "call setup".

• 25 As such, Internet users are free to access any part of the Internet at the same cost, regardless of distance to the access party. Of course, the cost for a link on another continent is much higher than for a local link. Thus, the capacity of the link to the other 30 continents is often very limited. Today, there are no simple solutions * that allow an ISP or IAP to charge more for users who use long distance links more than others.

It is an object of the invention to provide and collect information from 35 3 105737 links used by a service provider or the like in order to obtain distance-based information regarding user-made connections.

It is another object of the present invention to use link mode routing protocol information to determine whether or not a data packet is being transported over a data link over the Internet.

According to a first aspect of the present invention, there is provided a method of collecting charging information regarding the use of a packet switched data network by a network user, comprising: generating a routing table comprising a set of destination addresses and a plurality of corresponding nodes in the next hopping network; assigning a cost class to at least one link or node in the data network; 20 assigning a cost class to each address area in the routing table depending on the links / nodes and corresponding cost categories through which the packet must pass to a particular address within the area; receiving a data packet from said network> 25 users and identifying its destination address; determining the associated cost category from the routing table based on the destination address; and incrementing the corresponding cost class calculator.

Preferably, the method includes classifying destination address areas into low and high cost categories.

Configuring these classes can. then rely on a simple list of outbound links with your ISP instead of listing all 35 possible destinations, eg at the national level.

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Several intermediate cost categories can also be defined. Such extensions require the use of separate packet / byte counters for each class.

5 Separate billing for outbound and endpoint connections can be used because the network access node can monitor traffic (TCP) which side of the network has initiated the connection. Such control is already used in firewalls for security reasons. Further, UDP traffic (User Datagram Protocol) can be followed (as in firewalls) by specifying that incoming UDP packets are included if they originate from the address to which the outgoing packets have recently been sent.

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Embodiments of the invention have the advantage that information regarding the "destination" reached by the user can be classified, and the classification is a relatively brief task. There may be 20 billing based on the actual transport costs incurred by the service provider and from which the user may be charged.

In the simplest form, only one is needed. memory access to retrieve "high-cost" tickets in addition to • • 25 routing of targets. No additional network traffic is generated.

The formation of high cost and low cost destinations uses a very simple list of links instead of listing a long and frequently changing destination list.

Solutions can be implemented locally by a single service provider without similar actions being performed elsewhere in the network.

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The invention is particularly well suited to the Internet where. the user accesses the open Internet through an Internet Service Provider (ISP). Preferably, the routing table, which contains the assigned 5 cost categories, is adapted to the Network Access Server (NAS) in the ISP through which the user accesses the ISPT's Local Area Network (LAN).

It will be appreciated that the invention may be applied to the collection of charging information associated with any packet switched data service. This includes web access, email, Telnet, FTP, etc.

Preferably, a "map" of the data network (or local area of the network, or "independent" area) is formed using the OSPF protocol to select the next hop for each set of destination addresses. On the basis of the shortest route identified, the cost class is allocated to this route, and thus to the associated destination address area.

According to another aspect of the present invention, there is provided a device for collecting charge information,? 25 for using a network_user packet switched data network comprising: a router in said network having a memory stored in a routing table including a set of destination addresses_ range and a set of matching; 30 next-hop network nodes; W · ........ L.

. ·. first processing means for assigning a cost class to at least one link or node in the data network; and other processing means associated with said-35 routers for assigning to each address area ..... in the routing table a cost class depending on links / nodes !, and the corresponding cost category, 6 105737 through which the packet must pass to an address within the area; which router is adapted in use to receive a data packet from said user of the network and recognize its destination address, and to determine a related cost class from the routing table based on the destination address; and the apparatus further comprising a plurality of calculators corresponding to respective cost ranges and means 10 for incrementing the cost class calculators on the basis of the specified cost class.

For a better understanding of the invention and to illustrate how the invention may be implemented, reference will now be made by way of example to the accompanying drawings, in which: Figure 1 is a block diagram of a system illustrating access to the Internet; Figure 2 is a block diagram showing in more detail the ISP in the system of Figure 1; Figure 3 is a flowchart of the charging method for the ISP of Figure 2.

. Figure 1 shows a single ISP 1 that is connected to the Internet 2. It is understood that thousands of ISPs around the world are connected to the Internet and provide access to countless users with Internet access. The connection between ISP-1 and the Internet 2 is via digital Ethernet transmission cable 3 or 30 other high-speed transmissions. A user who wishes to access the information and / or interactive services available on the Internet from ISP 1 may be an individual who accesses the Internet via fixed terminal 4. Terminal 4 is connected via POTS connection 5 (Plain Old 35 Telephone System) to the user's local exchange. ; (LE; Local Exchange) 6 or a Transfer Center (TE; Transit

Exchange) via 7 modems (not shown in Figure 1).

The 105737 LEs and TEs 6, 7 are interconnected via central lines 12. The exchange (s) 6, 7 connect to the ISP 1.

f --------- 5 It will be appreciated that other Internet users may access the Internet 2 via a wired connection 8 from a corporate local area network (LAN) 9 using ATM or the like. Small companies 10 may also have a limited number of connections to the Internet 2 10 via telephone connections via PBX 11. In addition, subscribers 13 of a digital cellular mobile network, which includes base stations 14, a mobile switching center 15 and connections 16, 17, can access the Internet through the same ISP 1.

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Figure 2 shows in greater detail the ISP 1 of Figure 1 and its connections to the communication network and the Internet 2.

The subscriber receives access to the ISP 1's Network Access Server (NAS) via modem pool 19, through ISDN access 20, through asymmetric data subscriber line (ADSL) connection 21, or through xDSL (not shown). , LE or TE 6, 7 (these components may be integrated with NAS). The NAS 18 acts as an interface for • · 25 circuit-switched transmission on the telecommunications side and packet-switched transmission on the Internet side. Typically, a point-to-point protocol (PPP; IETF RFC 1661) connection is established between the subscriber terminal 4 and the NAS 18. NAS 30 18 also provides an initial routing of data packets toward their * final destinations.

The ISP 1 typically includes a plurality of additional interconnected routers 22, which may be close to each other 35 or geographically located. . separately. These routers carry data packets »· forward to links 23 that lead from ISP 8 105737 to external networks. The links may include a local link to a local network 24, a national link to a national network 25, an international link to a neighboring national link 26, and an intercontinental 5 link to national networks 27 on another continent. ISP 1 may also be linked to other ISPs (which generally use ATM), although these links are not shown in Figure 2.

Within the ISP 1, local Web servers 28 may be connected to specific NASs / routers on a local area network (LAN). These servers act as Internet content providers. The ISP 1 also has one or more proxy servers 29, whose function is generally known, but which will in any case be described below.

The data packet is routed based on the IP address specified in ISP 1 and elsewhere in the Internet 2. The address is a 32-bit address assigned to hosts 20 present on TCP / IP Internet and consists of a network part and a host part. This division facilitates efficient routing. Internet users are more familiar with Domain Addresses, eg "www.ericsson.co", although these correspond to IP addresses that are converted in ISPr • «25 1.

Each Internet 2 router, including those routers 22 that are controlled by ISP 1 and NAS 18, are provided with a so-called. routing tables. The routing table 30 contains a list of IP address groups along with a list of corresponding nodes, i.e. routers, hosts, etc., which correspond to the next hop of the data packet. The routing table can take the following form: • «9 105737 destgrpl nxthopl, destgrp2 nxthop2 5 destgrp3 nxthop3 destgrp4 nxthop4 where" destgrp # "identifies the range of IP addresses and" nxthop # "identifies.the router directly connected to the router table that is connected to 10. . When a data packet is received by a router, the routing table is searched based on the corresponding IP address to identify the next router in the chain.

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The routing tables are not static, but rather dynamically modified according to changes in the physical and operational structure of the Internet. At a given destgrp, the router uses a protocol called Open 20 Shortest Path First (IETF RFC 1583) to determine nxthp based on the information received from the router by other routers.

• '- • · __ 25 Regardless of the fact that the routing table only contains the next hop for a specific IP address range, the router still needs an internal "map" of the surrounding Internet area to determine this next hop. When examining ISP 1 of Figure 2, the map 30 formed by NAS 18 may include an ISP network * along with cross-border links 23. It is, therefore, to be understood that using this map it is possible to determine through which types of links a data packet directed to _._ an IP address in a given 35 address range (destgrp #) is passing or likely to pass. ; passes through.

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For the purposes of the present invention, Internet links are classified into two types of cost, high cost and low cost. These are determined in a fixed list in the NAS 18 memory. High cost links are those links 5 that connect the ISP network to foreign networks 26, 27 while the low cost links connect to local and national networks 24, 25 and other ISPs and IAPs. Within ISP 1, links are also classified as low cost links. The cost categories are shown in the third column 10, which is appended to the routing table (shown in Ref. 30 in Figure 2) on the NAS 18, indicating whether or not a data packet routed to an address included in destgrpr via a high cost link. For example: 15 _ destarpl__nxthool__High_ destgrp2 nxthopl Low destgrp3 nxthop3 Low destgrp4 nxthop4 Low 20 destgrp5 nxthop5 High

It is to be understood that destgrp can also be subdivided and compared to conventional routing tables. including some subgroups associated with high cost links and others not. For example, destgrpl and destgrp2 both share the same nxthop but are categorized differently in the cost column of the table.

As already described, conventional Internet billing systems allow subscriber billing based on the time used and the number of packets transmitted. The latter is performed using a packet calculator included in NAS 18. To utilize the information contained in column 3 of the modulation routing table, a pair of 35 calculators is included in NAS 18. The first calculator 31 of which contains the number of packets transmitted by NAS 18 at least one 105737 over a high cost link, while the second calculator 32 includes the number of other forwarded data packets. It will be appreciated that the NAS 18 has v detailed information about the origin of the data packets 5, i.e. subscriber information, and is thus able to provide billing information to the ISP billing collector (not shown in Figure 2). Alternatively, the NAS 18 could send billing information to a billing collector that is part of a telephone network.

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The above method is further illustrated in the flow diagram "" (Steps 100-107) in Figure 3.

Instead of using the OSPF protocol map 15 to determine destgrp cost categories, NAS 18 can use "dumb" packet transfers to track the route to the destination via the Internet. Internet protocols such as ICMP (shown in IETF-RFC 1393) and utilized in programs such as TRACEROUTE can be used for this purpose. However, this application generates a little extra network traffic each time a user connects to a new server on the Internet, and causes additional functionality with each packet. Shark-. nevertheless, route tracking can be used if link mode routing information is not available. If it is not known initially whether the destination address will be reached via the high cost link, the tracking program may initiate tracking to identify this information.

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Adaptation of the proxy server 29 to the ISP 1 has already been mentioned. The proxy server 29 maintains web pages that have been downloaded by subscribers for a predetermined period of time. The address of Proxyserver 29 is configured as the subscriber's web browser 35 so that all retrievals of web pages go. first, the proxy server 29. The server 29 checks its memory for each request and provides the requested page from its own 12,105,737 memory, if any. Otherwise, the proxy server 29 retrieves the page from the Internet in the normal way.

In particular, if the web page requested by the subscriber is not already in the memory of the proxy server 29, the retrieval request is analyzed by the above mechanism, and it becomes clear whether the request 10 has to be passed through the high cost link.

The proxy server 29 collects the information and subsequently sends it to the ISP's billing system.

If it is desirable for the subscriber to be billed regardless of whether the requested page is found in the memory of the proxy server 29, the server 29 may add a cost flag to each web page stored in its memory.

The cost of these pages can then be added to the subscriber's bill, even though the pages are actually down-20 data from the proxy server 29. Alternatively, the cost of retrieving the document from the high-cost link may be covered by sharing the cost between all

f 25 Separate billing can be applied for outbound and end-to-end TCP connections. This is possible because NAS 18 can follow TCP layer traffic to determine which side has initiated the connection. Such control is already used in firewalls for security reasons. Similarly ·. 30 UDP traffic can be monitored (again, as in firewalls) by checking for incoming UDP packets that are part of the connection to determine whether they originate from the address to which the outgoing packets were recently sent.

35 The firewall system can be used to control access to the World Wide Web, and the user can enable or disable access using an applet that is linked to a billing system. The solutions presented here can be combined with such structures, allowing access at many levels: local, servers, national, continental, international 5, etc. The configuration of these levels is then based on the list of links from the access node to list all possible destinations, e.g. level. By firewall, it is meant that data packets are filtered when entering a security system on a router connected between two networks to determine, from the packet content, whether it is of a type that can be transmitted to another network.

It will be appreciated that the ISP network and routers are generally protected by suitable firewalls and source address filters. If not used, Internet users may potentially revolutionize routing protocols or ICMP packets ....... However, firewalls within the ISP network must be able to pass through the tracking software and routing protocol packets.

One skilled in the art will appreciate that the above embodiments may be modified without departing from the scope of the present invention. For example, although a modified routing table containing cost classifications is shown to be included in NAS 18 of ISP 1, it may alternatively or additionally be included in one or more. V 30 of Routers 22. "At this time, a modified billing system may be used to collect billing information from a plurality of distributed calculators. According to another modification, links may be classified into more than two classes (High and Low), as described above.

35 For example, national links can be classified as Medium Cost Links.

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The above embodiment relates to billing subscribers based on outgoing packets. If desired, NAS 18 (or another router 22) may bill based on incoming data packets based on the source address of the packet. However, this results in additional costs that are roughly equivalent to single packet routing decisions.

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Claims (5)

A method for collecting billing information relating to a user's (4) use of a packet switching data network (2), in which a router (1, 18, 22) method is designing a routing table containing a method destination address ranges and a method corresponding to network nodes for the following blasts, characterized by the steps: providing a cost class for at least one link (23) or node in the data network; for each address range in the routing table, one assigns a cost class that depends on the links / nodes and corresponding cost classes through which the packet must pass to reach the address within the range; receiving a data packet from said user (4) and identifying the destination address of the packet; On the basis of the destination address, the cost table is determined from the routing table; and incrementing a corresponding counter (31, 32) for the cost class A method according to claim 1, characterized in that the data network is the Internet (2) and that the user becomes available to the Internet via an Internet service provider (ISP, English Internet Service Provider) (1). Method according to claim 2, characterized in that the routing table containing the specified cost classes has been obtained in the ISP's network access server (NAS), via which the user has access to the ISP's ISP. local networks. . 35 Method according to claim 2 or 3. characterized by designing the routing table using an OSPF protocol to select the following burst for each group of destination addresses, and allocating a cost class for the basis of the identified shortest path. route and thus for associated destination address range. An apparatus for collecting billing information relating to a user's use of a packet switching data network (2), the apparatus including a router (1, 18, 22) having a memory where a routing table is stored containing one way of destination address ranges and one corresponding network node for the following burst, characterized in that the apparatus contains first processing means by which a cost class is assigned to at least one link (23) or node in the data network; and other processing means associated with said router and by means of which a cost class is assigned to each address range in the routing table on the basis of the links / nodes and corresponding cost classes through which the packet must pass in order to reach a certain address within the range; Wherein the router (1, 18, 22) is adapted to operationally receive data packets from said user (4) of the network (2) and to identify the packet's destination address, and to derive the corresponding cost class on the basis of the destination address; 30 to which the apparatus further includes a method of calculators (31, 32) corresponding to respective cost classes, and means for incrementing the cost class counters on the basis of the derived cost class. φ <i