WO2008031753A1

WO2008031753A1 - Method for providing centrex service features in a peer-to-peer network

Info

Publication number: WO2008031753A1
Application number: PCT/EP2007/059292
Authority: WO
Inventors: Mohammad Vizaei
Original assignee: Nokia Siemens Networks Gmbh & Co. Kg
Priority date: 2006-09-14
Filing date: 2007-09-05
Publication date: 2008-03-20
Also published as: DE102006043233A1; DE102006043233B4

Abstract

The invention relates to a method for providing Centrex service features in a peer-to-peer network. This involves a special identification being inserted into an identifier or an address for a subscriber in a peer-to-peer network. This identification then identifies the subscriber as a Centrex subscriber. In the peer-to-peer network, when a call is being set up, for example, the subscriber is then identified as a Centrex subscriber by a search algorithm, such as a Chord algorithm, using this identification. This allows the subscriber to use Centrex service features such as call diversion or forwarding, call acceptance, etc., in the peer-to-peer network. The Centrex service features and the call setup can be implemented in the peer-to-peer network on the basis of the Session Initiation Protocol SIP, for example, which has been defined by the Internet Engineering Task Force IETF in Requests for Comments RFCs, such as RFC 3261. By entering an identification which is used to identify a subscriber as a Centrex subscriber in the peer-to-peer network into an identifier or an address (e.g. e-mail address etc.) for the subscriber, it is a simple matter to form a Centrex subscriber group without an additional, cost-intensive central system. This Centrex subscriber group can then easily be provided with Centrex service features in the peer-to-peer network on an SIP basis.

Description

description

Method of offering Centrex features in a peer-to-peer network

Technical area

The invention relates to a method for offering Centrex features in a peer-to-peer network.

State of the art

In telecommunications technology, the term Centrex (Central Office Exchange) generally refers to the outsourcing of the functionality of a private branch exchange (PBX) in the public telephone network. A telephone company or a Centrex service provider provides this knot on the platform of a public placement or a so-called Centrex server a group of so-called Centrex users (eg employees of a company or a company the functionality of a PBX system ^¬ with home workstations, etc.).

The Centrex participants - one mostly closed

Service area (for example, a company, a multi-site or home-based company, etc.) - are considered as a related group - a so-called Centrex group. If, for example, various company locations are combined to form a Centrex Group, they will receive their own company-wide numbering plan - a so-called Centrex numbering plan. Conversations from one company location to another can be made e.g. be calculated at reduced rates or internal calls, e.g. also be toll free.

In such a virtual PBX operation management, implementation and maintenance of the Call processing software usually centrally. In principle, the use of Centrex by, for example, a company assigns all tasks usually occurring in connection with the private branch exchange (eg maintenance, installation of new hardware and software components, etc.) to the telephone provider or the Centrex service provider.

By Centrex to Centrex subscribers, a Centrex group are provided through local loop service or performance ^¬ features which were previously available only within private branch exchanges. In the context of Centrex, these features can also be referred to as Centrex performance features. The Centrex features, for example, the operation of a

Facilitated and simplified subscriber connection or extended the communication option. Such Centrex features include call forwarding, call diversion, call pickup within a particular Centrex subscriber group, call queue, etc.

Today, many companies often use IP-based communication networks. These communication networks can be designed, for example, as a so-called peer-to-peer network. Peer-to-peer networks are particularly well suited for so-called home networks, for smaller corporate networks and applications in the business sector.

The term peer-to-peer, abbreviated P2P or P-to-P, usually denotes an equal relationship of units involved in a communication (eg peer-to-peer-capable terminal, computer, computer, etc.), which also as Peer and which are used by participants for communication. Peer-to-peer is therefore also seen as a synonymous name for a communication among equals. Peer-to-peer networks are therefore networks without central access control, in which, for example, all computers are equal or all participants act on an equal footing. In a peer-to-peer network, therefore, each peer can use both services or data as well as provide other users with services or data. The peers (eg computer, computer, peer-to-peer-capable terminal, etc.) can be used by the participants as workstations, but also take over tasks in the network.

The opposite of the peer-to-peer network is the so-called client-server system, in which there is a so-called server on the one hand, from which services are offered, and on the other hand so-called clients, of which the services offered are used. In the peer-to-peer network, this role distribution is suspended for the participating peers. In contrast to a client-server system, a connection in a peer-to-peer network exists directly between two peers or the computers of two users without the intervention of a network server.

Peer-to-peer networks can be used for a variety of purposes. They are used in particular for the exchange of information and / or data such as file sharing for music or video files, games, etc. However, peer-to-peer networks are also used for services such as instant messaging, where subscribers can communicate (chat) in real time with other subscribers through short text messages. Furthermore, peer-to-peer networks are also used for so-called grid computing - as it is often used in biotechnology or computer technology organizations. Grid computing can also be referred to as "distributed computing" where unused CPU power and / or free space of other computers is used in the peer-to-peer network when computer-intensive computer processes are required. Recently, peer-to-peer networks have also been used for so-called IP telephony or Voice-over-IP, which includes telephoning over a computer network according to Internet standards. In the peer-to-peer network, calls from peer to peer are made possible, whereby, for example, this can be carried out independently of servers such as so-called proxy servers or security programs (eg so-called firewalls in routers).

The peer-to-peer network forms e.g. When exchanging information or when using IP telephony, a so-called "closed" communication network, this means that only currently active participants in the peer-to-peer network are involved in the exchange of information or can use IP telephony. A participant is said to be active when it is enrolled in the peer-to-peer network, and each participant in the peer-to-peer network is assigned resources such as IP address, identifier, e-mail address, etc., where these resources can be summarized, for example, in a so-called user profile.

The resources can be divided into so-called dynamic and so-called static resources. Dynamic resources such as the IP addresses are only available in the peer-to-peer network if the respective user is actually logged on. Static resources such as The identifier or e-mail address is always available for the peer-to-peer network, even if the corresponding subscriber is not logged in or e.g. his computer is switched off.

Nowadays, many companies often use IP-based communication networks, whereby these networks can also be used for IP telephony, for example as peer-to-peer networks. It is interesting, the participant for the IP telephony Centrex features such as call forwarding, call forwarding, Call transfer, etc. in the IP-based communication network to provide.

Thus, for example, it is possible for the subscribers to use a Voice over IP or Multimedia over IP standard (for example via H.323, SIP or MGCP) with the service server from which the Centrex features in the communication network (eg the peer to peer network), to network and thus to become Centrex participants. In this so-called IP-Centrex the

Centrex features typically realized by software on one or more central servers. As in the case of the traditional Centrex, the administration of the Centrex features and the management of the Centrex subscribers is also carried out centrally by, for example, IP-Centrex. a Centrex service provider.

However, integrating such an IP Centrex service server, from which the Centrex features are made available to the subscribers, into a peer-to-peer network has proven to be disadvantageous in that this service server is a centralized system in which all Centrex participants must be administered. That is, any change (e.g., establishment, modification, or deletion of a Centrex subscriber profile, enabling or disabling a Centrex feature, etc.) can only be made through this central service server. In addition, appropriate facilities (e.g., service servers, etc.) must be offered and operated in the peer-to-peer network. This results in the operator of the peer-to-peer network e.g. additional costs and major installation and administration costs.

Presentation of the invention

The invention is therefore based on the object to provide a method with the Centrex features in a peer-to-peer network without the involvement of a central system realized and made available to participants.

The solution of this object is achieved by a method of the type mentioned, by which in an identifier or an address of a subscriber in a peer-to-peer network an identification is inserted, by which the subscriber is designated as a Centrex subscriber, in which case is recognized by a search algorithm based on this identification of the subscribers as a Centrex subscriber, and then allowing the subscriber to use Centrex features in the peer-to-peer network.

The main aspect of the proposed solution according to the invention is to offer Centrex features to peer-to-peer subscribers in a simple manner without the use of one or more central service servers in the peer-to-peer network. In the method according to the invention, already existing computers and systems are advantageously used and thus no - often expensive - additional facilities (for example service servers, etc.) are necessary, which must be made available and / or operated by the provider. An expensive central administration of the Centrex participants is also not necessary. The entry of the identification, on the basis of which a subscriber is recognizable as a Centrex subscriber, in an identifier or an address (eg e-mail address, etc.) of the subscriber can already during the registration of this subscriber in the peer-to-peer network be carried out in a simple manner so-called Centrex groups. Another potential is that the inventive method - combination of peer-to-peer network and Centrex features - can be easily integrated into an environment with today's common office software (e.g., Microsoft Office products such as Microsoft Outlook).

It is advantageous if a so-called chord algorithm is used as the search algorithm in the peer-to-peer network. The Chord algorithm was developed as a peer-to-peer search algorithm within the framework of the so-called Chord project at the Massachusetts Institute of Technology (MIT) (see "The Chord Project", MIT Laboratory for Computer Science; http: // pdos. csail.mit.edu/chord) This algorithm enables peers to be efficiently determined based on a given key such as a centrex participant identification.

It is useful if for a call setup and / or a

Realization of the Centrex features in the peer-to-peer network the so-called Session Initiation Protocol SIP is used since SIP is a signaling protocol defined by the Internet Engineering Task Force IETF in a so-called Requests for Comments RFC, the RFC 3261. represents over-IP or IP telephony.

An expedient development of the method according to the invention provides that the Centrex feature Call Forwarding (Call Forwarding) is offered based on SIP in the peer-to-peer network. Since different call forwarding cases have already been resolved and defined for SIP, these can be used to implement this Centrex feature when using SIP in a peer-to-peer network.

A preferred embodiment of the invention provides that the Centrex feature Call Diversion (Call Transfer) based on SIP in the peer-to-peer network is offered. For call forwarding, different scenarios have been defined for SIP. When using SIP in a peer-to-peer network, these can be easily used to implement the Centrex call forwarding feature.

It is very convenient to use the Centrex call pick-up feature on the peer-to-peer network. It is also expedient if defines a call pickup group in the peer-to-peer network in which an entry for the call pickup group is stored locally on the peer of an authorized centrex subscriber and then announced to the other Centrex subscribers of the call pickup group. Then, in the event of an incoming call, the Peer of the called Centrex subscriber of the Call Pickup Group sends a message to all other Centrex members of the Pickup Group and displays this message to the other Centrex members of the Pickup Group. This makes it easy to set up the "Call Transfer" feature locally in the peer-to-peer network for a group of Centrex participants (eg employees working on the same project or in the same room, etc.) Call transfer group, which belongs to the Centrex participants, is locally registered, for example, as a resource for this participant in the peer-to-peer network and then informed the other participants an authorization of this participant for the call pickup group.

In certain cases, it can also be advantageous if the Centrex feature call queue (Call Queuing) is implemented locally in the peer-to-peer network based on SIP. In this way, the Centrex Call Queue feature can be implemented locally on the peer-to-peer network.

For this purpose, it is furthermore advantageous if a first incoming call to a Centrex subscriber is put through. However, further incoming calls to this Centrex subscriber will then be locally connected to an announcement, replicating a so-called Real-Time Transport Protocol (RTP) stream for each incoming call. RTP is a protocol for continuous transmission of audiovisual data (= stream) over IP-based networks. Since the announcement from the respective peer, which usually also has a so-called SIP client for IP telephony, is made available locally, is for the realization of this feature is not a central system - eg for the announcements - necessary. Calls waiting in the call queue can be displayed to the Centrex subscriber in a simple manner, for example on a peer-associated output device. Only when a call is taken from the call queue, on the one hand, the corresponding RTP stream is disabled again and on the other hand, the waiting call, for example, using the so-called SIP Redirect method again converted into a normal call. It is also beneficial ^¬ way, if an upper limit for a number of calls in the call queue held is defined.

Brief description of the drawing

The invention will now be described by way of example with reference to the accompanying figure. FIG. 1 schematically shows the sequence of the method according to the invention for offering Centrex performance features in a peer-to-peer network.

Embodiment of the invention

The exemplary embodiment of the invention is based on a combination of the so-called Chord algorithm, which was developed within the framework of the Chord project at the Massachusetts Institute of Technology (MIT), as a search algorithm in the peer-to-peer network and the Session Initiation Protocol SIP for establishing a call with Voice-over-IP or IP telephony. Because an application of SIP, for example, peer-to-peer enabled devices (eg subscriber computers, work ^¬ station, etc.) with an additional software for SIP - be equipped - so-called SIP clients. The inventiveness emäße method, however, is also applicable to other search algorithms ^¬ or other protocols for Voce over IP, such as H.323, MGCP, etc..

The method begins with a starting step 1. In a second method step 2, an identification is determined for Centrex subscribers. This identification can For example, be designed as a string (string) and eg "centrexl" read.

In a third method step 3, the identification - e.g. the string "centrexl" - inserted into an identifier or address of a participant in the peer-to-peer network, which shall also be a Centrex participant in a Centrex participant group, for example, the string "centrexl" may be used to register a participant in the peer to-peer network eg into an identifier or address, such as "Alice.wonderland@somenet.com" of the subscriber may be inserted such that the identifier or address is extended, for example, to "alice .wonderland. CentrexlQsomenet. Com". The use of such a designed, extended identifier or address offers the advantage, in particular when using SIP for call setup, that this identifier or address including the inserted identification corresponds to the format of the so-called SIP Uniform Resource Indicator (SIP-URI), as defined in RFC 3261 Of course, other formats are also conceivable for an extension of the identifier or address of the subscriber with the identification for Centrex.

In a fourth method step 4, the subscriber is then replaced by inserting the identification - such as e.g. of the

Character string "centrexl" is marked as a Centrex subscriber in the peer-to-peer network, whereby the participant is identified by the identification (eg "centrexl") not only as a Centrex participant but also as a member of a specific Centrex participant group. A Centrex subscriber ^¬ group is characterized by the use of the same ID (for example "centrexl") for all group members, that is, for example, the string "centrexl" is inserted in identifiers or addresses of all those participants who also a member of this Centrex subscriber group should be. In a fifth method step 5, Centrex subscribers belonging to a particular Centrex subscriber group are then determined by a search algorithm such as the Chord algorithm. The search result - ie all those identifiers or addresses of subscribers or peers in the peer-to-peer network which have the identification (eg "centrexl") can be used as search key then, for example, the peers or respectively associated SIP clients belonging to this Centrex subscriber group are communicated.

In a sixth method step 6, Centrex features, such as call forwarding, call forwarding, call pickup, call queue, etc., are then made available to the Centrex subscribers in the peer-to-peer network, whereby it can be defined before the definition of the Centrex subscriber group. which Centrex performance ^¬ features should be available for the group participants or can be used by the group members. An embodiment of the Centrex performance features - as exemplified below for call forwarding, call diversion, call pickup or call queue - can be done, for example, based on SIP.

For the realization of Centrex features such as e.g. Call forwarding and call forwarding can be used in the peer-to-peer network when using SIP solutions already defined for SIP.

For the realization of the Centrex service feature call ^¬ takeover a so-called call pickup group is first defined, for example by an additional entry in the resources (for example, user profile) or for example locally in the SIP client in the peer of a participant, which both Centrex

Participant is and should be a member of a specific call pick ^¬ group. This information is then transmitted to all other SIP clients of those peers or Centrex subscribers, which also belong to this call pickup group. If a Centrex subscriber of a particular call pickup group is now called, then a notification is sent to all members or to the corresponding peers or the SIP clients in the call pickup group that are running on this incoming call. This notification can then be displayed by these peers to the respective participant. The call can then be accepted by a subscriber of the call pickup group. To implement this feature - especially when using SIP - it is also possible, for example, to use RFC 3891 of the IETF.

For example, the Centrex Call Queue feature can be implemented locally on appropriate peers or SIP clients. A first incoming call to a Centrex subscriber in the peer-to-peer network is accepted by that subscriber. Each further, incoming call, which is to reach the subscriber during the first call, is answered by connecting this call locally from the peer with an announcement.

For example, a so-called real-time transport protocol stream or RTP stream can be used for the announcement. RTP is a protocol for the continuous transmission of audiovisual data (= stream) over IP-based networks. For each incoming call, the RTP stream is then replicated. In addition, an upper limit can be defined as to how many incoming calls are to be kept in the call queue. For example, calls waiting in the call queue may be displayed to the subscriber on a peer-associated output device (e.g., screen, display, etc.).

If a call is taken from the call queue, then the corresponding RTP stream is deactivated first. The call is then sent e.g. using an existing method, e.g. the SIP redirect method of the peer or the associated SIP client connected to the subscriber.

Claims

claims

A method for offering Centrex features in a peer-to-peer network, characterized in that an identifier is inserted in an identifier or an address of a subscriber in a peer-to-peer network, through which the subscriber as Centrex participants will then be tagged by a search algorithm based on this

Identification in the identifier or address of the participants is recognized as a Centrex subscriber, and thereby allowing the subscriber to use Centrex features in the peer-to-peer network.

2. The method according to claim 1, characterized in that a so-called chord algorithm is used as a search algorithm in the peer-to-peer network.

3. The method according to any one of claims 1 to 2, characterized in that the so-called Session Initiation Protocol SIP is used for a call setup and / or a realization of the Centrex features in the peer-to-peer network.

4. The method according to any one of claims 1 to 3, characterized in that the Centrex feature call forwarding (Call Forwarding) is offered on the basis of SIP in the peer-to-peer network.

5. The method according to any one of claims 1 to 4, characterized in that the Centrex feature Rufumleitung (Call Transfer) is offered based on SIP in the peer-to-peer network.

6. The method according to any one of claims 1 to 5, characterized in that the Centrex feature Call Pickup (Call Pickup) is offered in the peer-to-peer network.

7. A method according to claim 6, characterized in that in the peer-to-peer network a call pickup group is defined, that an entry for the pickup group is stored locally on a peer of an authorized Centrex subscriber and then the other Centrex subscriber Call Pickup Group subscribers are notified that on an incoming call from the peer of the called centrex subscriber of the call pickup group a message is sent to all other Centrex members of the pickup group, and then that message is sent to the other Centrex users the call pickup group is displayed.

8. The method according to any one of claims 1 to 7, characterized in that the Centrex feature call queue (Call Queuing) is implemented locally in the peer-to-peer network based on SIP.

A method according to claim 8, characterized in that a first incoming call to a Centrex subscriber is put through that further incoming calls to that Centrex subscriber are locally connected to an announcement, a so-called RTP stream for each incoming call is replicated, and that when a call is taken from the call queue, the corresponding RTP stream is deactivated again.

A method according to claim 9, characterized in that an upper limit is defined for a number of queued calls.