CA2332567A1

CA2332567A1 - Integrated data centric network (idcn)

Info

Publication number: CA2332567A1
Application number: CA002332567A
Authority: CA
Inventors: Patrick Siu; Yair Bourlas; Richard J. Nowak; Wendy S. Smith; Wing F. Lo
Original assignee: Individual
Current assignee: Nortel Networks Ltd
Priority date: 1998-06-02
Filing date: 1999-06-01
Publication date: 1999-12-09
Also published as: EP1084551A1; CN1129275C; JP4817497B2; US6522641B1; JP2002517948A; BR9910869A; WO1999063710A1; CA2256282A1; CN1304606A

Abstract

A fixed wireless point-to-multipoint distribution network for providing seamless communication coverage to a plurality of subscribers that includes a plurality of base stations for providing wireless access to said subscribers ; each base station having connectivity to one another on a first network laye r via at least one of a number of IP and/or ATM switches, called IDCN switches ; each IDCN switch having connectivity to another over a second network layer via a transport ring thereby enabling one user to communicate directly with another user in said first network layer, or externally of said first networ k layer via one of said IDCN switches. An integrated data centric network is provided that integrates voice, data and video services into a single networ k, defines user services by the end user by providing middleware to enable the end user to develop services and applications; and provides a carrier grade service with distributed networking and services.

Description

24 MAY '00 14:23 FROM HARLGW IP LAW GROUP TO EPO - MUNICH PAGE.007i020 Atq. Dock. Na 1V'I1..3.4.002I2156 TITLE OF THE ~1VENTION
1~
fNTEGRATFD DA?A CI~TTRIC NETWORK (~7CN) BACKGRQUND OF THE Il'~TVENTION
Field of the Invention 20 This invention related to a fixed wireless point-to-point and/or point to-multipoint communication system but more particularly, to as Integrated Data Centric Network (IDCN) wherein voice, data and video services arc int~etCd on the same network.
25 Discussion of Relaaod Art Traditional fixed wireless access networks have, in the past, had to use separate networks iu order to provide voice anal data services to remote customers.
The voice network offers the best quality of service to the customers, but lack the efficiency reriuires for data transport. The data network, in particular the IP
30 network, offers the data transport cffciency, but lack the quality of services requited by voice and video services. in addition, since the inteltigertce was actually contained within the network, the customer services were actually defined by the network and therefore new services cannot be easily deployed and commercialized as well as the services arc not easily portable. These types of networks wherein the 35 intelligence is contained within the network, makes use of dumb terminals and services and featwos are controlled by the service providers and switching equipment. Any such services are offered through complex signaling protocflls aad are therefore slow to be introduced.
lA~~'a~f~i'~C~ SH

24 MAY '00 14:23 FROM HARLOW IP LAW GROUP TO EPO - MUNICH PRGE.008i020 There are a number of documents which discuss the utilization of networks.
For example, the EPO patent 0 657 074 A2 reveals a communication system for the provision of voice andlor data services to a set of terminals either in the form of teleptyvnes ar any other kind . Next, the WO 97/4819I patent reveals a fow Bower rnulti-cellular, bmadband communication system for the unidirectional (i.e.
broadcast), bi-directional and me~ltidirecbonal transnussion and reception of voice, video, audio, television and data signals provided within the context of a point to multipoint network topology.
EPO patent 0 818 940 A2 reveals a method for transporting a SONETISDH
formatted asynchronous transfer made (ATM) signal andlor a synchronous transfer mode (5TM) signal on a line switched ring over a unidirectional path. The U.S.
patent 5,537,41 i discloses a novel architecture for an access network of a mobile radiotelephony network formed by dual bus for a dual counter-rotating ring to which there are connected an access point and several base stations capable of receiving several mobile stations and offering a virtual circuits service using cells whose header indicaxes the virtual circuit number or identifier.
Next, a Wile G E. Et. aL article, "'The Architecture of the DPN data Networking System," discusses the benefits of evolution from a sound technological product bast. Northern Telecom's strategy for evolving its packet data communications products to meet DPN product objectives is descn'bed in the article.
Next, a Ray Hunt article, "ATM - Protocols and architecture" descn'bes the ATM
protocol, technology and architecture, as well as the issues which it is designed to solve. These types of networks have resulted in a high cost of network maintenance for customers.
Accordingly, a need exists for an integrated data centric network wherein voice, data and video services are integrated within the network In addition, a need exists for irnegrated data centric network wherein services are defined by the user and enable service portability. Finally, a need exists for integrated data centric network wherein the voice, data and video services have the quality of services of the traditional voice networks; and transport efficiency of the traditional data. (IP) networks.

~;At~f~~i D S~~ET

24 MRY '00 14:24 FROM HRRLOW IP LRW GROUP TO EPO - MUNICH PRGE.009r020 BRIEF SUMMARY OF TIC IhTVEhITiON
The present invention relates to a fixed wireless point-to-multipoint distribution network for providing seamless communication coverage to plurality of subscribers, characterised by:
a plurality of base stations for providing wireless access to said subscribers;
each base station having connectivity to one another on a first network layer via at least one of a number of switches; and each of the switches having connectivity to one another over a second network layer via a transport thereby enabling one user to communicate directly with another user in said first network layer via one of said switches.
An integrated data centric network is provided that integrates voice, data and video services into a single network; defines user services by the end user by providing middlewarc to enable the end user to develop services and applications;
and provides a carrier grade service with distributed networking aid 5erviCCS.
BRIEF DESCR~TION OF THE SlrVEItAI. Vl~'WS OF TIE DRAWING
Particular embodiments of tlxe invention will be descn'bed in association with the following drawings, is which:
Figure 1 is a block diagram of a prior art fixed wireless point~to-mnltipoint network;
Figure 2 is a block diagram illustrating the transport of voice and data (IP
and Frame Relay) services over the prior embodiment of Figure 1;
Figure 3 is an illustration of the fixed wireless point to-multipoint network of the gresant invention;
Figure 4 illustrates the multiple transport layers for the fixed wireless point-to-multipoint system of the present invention;
Figure ~ is a functional block diagram illustrating the network architecture of the fixed wireless point-to-multipoint system of the present invention;
Figure 6 is a functional block diagram of the control and management functions for the fExed wireless point-to-multipoint system of the present invention;
and Figure 7 is a functional bloc: diagram of the subset controller for the fixed ~,a4.f~.4~EG SHEET

24 MAY '00 I4:Z4 FROM HRRLOW IP LRLI GROUP TO EPO - MUNICH PAGE.010i020 wireless point-to-multipoint system of the present invention.
DETATLED DESCRIPTTON OF THE PRfiFERRED BMBOD1MLNT
S Facilitate the description of the present invention, the following abbreviations have been used:

CPE Customer Premise Equipment DHCP Dynamic Lost Configuration Protocol DMAT Dynamic Modulation Adaption Technique DPAT Dynamic Power Adaption Technique DS Digital Signal (A Bellcare term in descn'hing the level of digital signal hierachy) DNS Dornaia Name Server Glt Generic Requirement (a Bellcore term for approved generic standard) IDCN Integrated l7ata Centric Network IP Internet Protocol, the context used in this document including all the network applications that run on top of the Internet Protocol LAN Local Area Nefwork LMCS Local Multipoint Communication Service LMDS Local Multipoint Distribution System MVDS Multipoint Video Distribution Service NliJ Network Interface Unit, a subscriber site device that provides the interface between ttie customer premise equipment and the wireless access network.

DAMP operation, Administration and Maintenance procedures P13X Private Branch Exchange PC Personal Computer POTS Plain Old Telephone Service PVC Peimantnt Virtual Circuit, a PVC is a connection that is set up using adrninishrative procedures 2a;~~.,i ~ci; S;'~EET

24 MAY '00 14:24 FROM HARLOW IP LAW GROUP TO EPO - MUNICH PAGE.O11i020 PSTN Public Switch Telephone Network SNMP Simple Network Management Protocol SVC Switched V'rrlual Circuit, a SVC is a connection that is set up using signaling procedures on a on-demand -(per call) basis TFTP Trivial File Transfer Protocol UNI User to Network Interface in an ATM network 'lPN V'>rtuaI private nehvork Fixed wireless point-to-multipoint access networks consist of topologies lfl having multiple overlapping cells, which provide coverage to an urban, suburban or rural area. The design of overlapping cell stmctureS will depend on the application but should ideally provide for link redundancy for customer sites as well as for the accommodation of new urban structures which may block previously available links.
Those systems that make use of wireless ATM access are designed around the concepts of frequency division multiple access (FDMA) and time division multiple access (TDMA). The FDMA is used for service bandwidths from DS 1/El and above (i.e. leasal lines) and TDMA is used for bursty tragic sources with rates specifically below DS1IE1. T17MA systems are designed to share bandwidth among many users, thus allowing for its grater efficiCncy whon dealing with bursty traffic sources. TDMA systems allow for bandwidth sharing, thereby providing for multiple barsty or low bit rate users to access the channel. The TDMA systems share a single demodulator between hundreds of users and are especially appropriate for l ObaseT ethemet, IP and POTS voice applications. FDMA systems, on the other hand, are designed to provide dedicated bandwidth to a specific user, with those users typically being leased line users that have fairly constant data rate requirements.
Wireless ATM systems allow for the use of braadband microwave infrastructure, thereby making effective use of the multicarrier nature of the broadband microwave system. These multicarrier systems allow for the best mixture of low entry costs of the network operator with flexibility to expand the cell range and traffic handling capabilities.

~:- .'.t":~'.f' ~~-1: ~'I
~!_9.4:~..,~~ ;.t a ..L.t 24 MRY '00 14:25 FROM HRRLOW IP t_RW GROUP TO EPO - MUNICH PAGE.012~620 Typically, at each cell site, there exists a base station consisting of microwave and digital radio equipment The base station provides the network connections, with the connections being typically OC3c ATM LTNI interface.
Base station microwave equipment is mounted on the top of the building, typically outside, and provides the wireless connection capability to the subscriber.
At the customer premises, outdoor microwave equipment (antenna integrated with transceiver) connects to a network interface. Cell sizes are typically 1-kilometers, depending an the frequency of the system operation, availability level which is req~xired by the system operator, and services performance that is required by the system operator. Generally, the wireless access system is designed to cost effectively support system requiring voice, vidca and data solutions, in which the number of customers is largo enough to wawant a point to-multipoint implementation. These types of systems include LMCS (Canada), LMDS (U.S. and worldwide) and MY)7S (J:nrope).
1 ~ Referring now to Figure 1, we have shown a block diagram of a wireless distn'bution syst~n according to the prior art. In this configuration, customers receive fixed wireless access to the telephone network via various customer premise cquigrnent Access is provided by means of a wireless link, communication tower and a base station. An ATM switch is used to provide access to various multimedia services, such as voice and data. The connection between the base station and the ATM switch might either be done via a leased line of a point to-point wireless link.
In order for a cusbomcr to access one of various services, such as voice, data, the ATM switch requires a coimection link to the PSTN (through the public network), a Link to IP network for Internet access or a link to a Frame Relay network for data communications. Similarly, a link may be provided to access other ATM
networks.
In a situation where tl~e subscriber rcyuires access or a Link with the PS'f N, the ATM switch is required bo be connected to the central office switch via a multiplexcr and concentrator as shown in Figure 2.
As illustrated in Figure 2, depending oa the castomer's sift configuration, the customer premise equipment can either be connecbod to x PBX via lOBaseT
ethernet link or an access node via a DS 1 link. The Customer situ is then linked to G
A~~NDE17 ~HEEi 24 MRY '00 14:25 FROM HRRLObJ IP LRW GROUP TO EPO - MUNICH PRGE.013~020 the base station via a wireless fixed access link. The base station consists of modulators, demodulators, and traasmitting/recciving radio equipment, which is connected to the ATM switch via either a leased line of a point to point wireless link. The ATM switch is then connected to a 2 to 1 multiplexer via a DS3 Iink.
The ATM switch is then connected to a 3 to 1 multiplexes via a DS3 link. The multiplexes then connects to the concentrator via a DS 1 link befocs being corunected to the central office switch via a GR303 signaling link As indicated previously, the shortcantings associated with this existing telecom network is that separate voice and data networks are required depending on the communication needs of the subscn-ber. Since access to various services may have different owners, customer services arc actually defined by the notwork as opposed to the customer. Similarly, by the very nature of the nthe service logic resides in the network thereby making service portability difficult to achieve.
The end-to-end network design is such that the network dictates to the customer the capacity and availability of a communication link to the customer. In other wards, regardless of the needs of the subscriber, the network will deliver what it can, when it can.
Another problem associated with the prior art telecom networks is that the intelligence is contained within the network. That is, subscn'bers arc provided with tecrnins3s wherein features and services are controlled by the switching centers.
Because the services are offered through complex signaling protocols, operators are slow to introduce new services and applications. Complex inter-working functions between protocols arc caused by the clear distinction between protovoIs used within the netvVOrk and the protocols between users of network and the protocols between users of network elements.
In view of this complexity, service operators do not Iike giving access to services and transport protocols to prevent any potential network failures.
This results in s limited amount of user-to-user signaling. This complexity fiu~ther results in a rigid billing straetun and a high cost of network maintenance fot the operator.
Referring now to Figure 3, we have shown a block diagram illustrating the nGtworl~ conf~gs~ration of the fixed wireless point-to-rnultipoint network of the present invention. The architecture of Figure 3 provides an Integrated Daxa Centric A.~'ENDED SHEET

24 MRY '00 14:25 FROM HNRLOW IP LRW GRGUP TO EPO - MUNICH PRGE.014~020 Network wherein voice; data and video network services become integrated. The network eonfiiguration enables service portability as well as user defined services required by individual users. Network parameters and requirements are dictated by a user's needs as opposed to the network needs. Bach end user is provided with an intelligent terminal, such as a PC, to enable service logic of the network to reside at the end user's terminal. The network, in effect, provides the middleware (signaling functions between the and user terminal and the network) to enable users to develop services and applications according to their needs, The network configuration illustrated in Figure 3 represents a hybrid ring, star, and mesh architecture wherein a plurality of base stations pmvide wireless access to a plurality of subscribers. Each base station has connectivity to one another on the first network layer via at least one of a number of IDCN switches. This enables one user to communicate directly to another user in this first network layer. As illustrated in Figure 4, each switch has connectivity tv one another on a second network layer over the hybrid ring.
As illustrated in higurc 4, at the nationallregional Ievel, a transport and routing layer is supported by means of multiple IDChT switches connected in a ring and star configuration, Similarly, at the metro distributifln levol and rooting layer, a transport ring and LAN arc utilizod between base stations with connectivity to IDCN switches to enable access to a higher level of layers. The routing layer enables a customer to access the 1DLN.network, IP network, frame relay network or the f STN public network via a getaway. The sub-layer to the metro distn'bution and muting layer is the accessflast mile layer where the base stun communicates over ~ccd wireless access to multiple customers identified as the customer premisos layer.
Referring nvw to Figure 5, we have shown a block diagram illustrating the artwork architccturc of the fixed wireless point to-multipoint system of the present invention. As indicated above, the distribution level is done an one layer between base stations and LDt"N switches. This enables the consolidation of back haul from the base station to IDCN switches, as welt as base station to base sfiation, thereby optimizing the routing for the distribution network. In addition, user-to-user traffic will stay within the network without going thmugh a third party network, thus ~',PYiEP~ICED SHEET

24 MRY '00 14:26 FROM HARLOIJ IP LA41 GROUP TO EPO - MUNICH PRGE.015~020 reducing the costs of network services. This configuration enables signaling between base stations, managing sections, and containing home location register for address of translationlregistration within the subnet controller. Depending on the user requirement, the 1DCN switch can access the H.323 servtrs,1;P gateway, ATM
gateway, prame Relay gateway or the telephony gateway for voice, data and video coanmunication with users from a third party network. The fixed wireless paint-to-multipoint system consists of several major system software and hardware blocks.
These are the point-to multipoint base stations for ATM or IP transport;
customer premise equipment; building interfaces; centralized compression; andlar network 14 operations center.
'The IDCN base station includes digital and microwave equipment designed to route ATM calls or IP packets to appropriate modulators, with ttte cells or IP
packets beimg transmitted to the subscriber population. The IDCN bast station also mutes traffic (ATM cells and IP packets) received from the subscnbcr equipment through the appropriate demodulators to the IDCN switch for muting to another IDCN switch, base station, gateway, etc.
The base station provides both FDMA and TDMA access alternatives.
Encryption is performed on a per logical channel per subscriber basis. Routing is perfons~ed on a logical channel basis. ATM signaling interfaces support SVC
and PVC connections. IP signaling interfaces support IP connections, t?pen NMS
interfaces as provided through the use of SNMf interface standards on all equipment including microwave transmitters cad receivers.. ATM OC-3c UhTI
r<etwork interface are provided for ATM connections and 1 bbBaseT network interface for IP connections. The base stations include both video network to wireless transmission equipment, as well as microwave transmitters, receivers, antennae and common equipment elements.
Refen~ng to Figure 6, we have shown the function block diagxam of the subset controller. Multiple and distributed subnet controller cast exist within a single lIIChT network. Each subnet controller conh~ols a segment (metropolitan area) of the >37CN network. Multiple subnet controllers form a peer to-peer central network. The key functions provided by the subnet controller are subsen"ber database, authentication, security, privacy, service portability managernent, call r';';;~hlDcD SHEET

24 MRY '00 14:26 FROM HRRLOW IP LRW GROUP TO EPO - MUNICH PRGE.016i020 controls, session managemcat and provisioning Referring to Figure 7, we have shown the block diagram configuration of the subnet controller. The subnet controller has two functional blocks, namely, interface and services. ~'he interface section provides the interface connections to other subnet controllers, tha network management center and to the IDGN
switches.
The service section provides server functions such as, 1. Policy server -- controls the bandwidth, Quality of Service, and access policies of the subscriber, 2. TFTP server-provides file transfer services for disldess clients;
t 0 3. DNS, DHCP server - provides address mapping and address resolution services;
DAMP, Billing - provides billing records collection, configuration management, fault management, maintenance and administration;
5. Session mutager - manages terminal login and co~mection sessions, I S Iogin authorizations;

6. Traff c raanagcr - provides real time tragic management, congestion control, call admission control;

7. Address binding serves-provides address binding betweea dii~erent layers;
20 8. Subscnber nnanagemcnt server - manages subscriber database, subscriber status, subscription profile;
9. Subscn'ber authentication server - provides subscriber authentication;
and 10. Authenticstion/Encryption key management - furnishes encryption key 25 management far subscriber authentication snd subscriber data encryption.
Based o~n the information and functions provided by the subnet controller, high speed tunnels can be established. bctwcca the subscribers for subscn'bers within the same netmork; and high speed tunnels can be established 30 between the subscriber and the gateway for connection to another subscriber in a third party network; therefore improving the muting efficiency and reducing networking costs of the network A".nf P!t?ci7 SI~~I:T

24 MAY '00 14:27 FPOM HARLOW IP LRW GROUP TO EPO - MUNICH PAGE.017i020 The link interface struts as a liaison (agent) to the external world (outside the subset controller). A typical cvegt flow is as follows:
An external request comes in through the link interface, which dc~ipbers the request, determines the procedures to he used, and generates requests to the $ appIOpTIAtC SCrVers for actions or information retrieval. Fach involved server acts an the request and generates the appropriate responses.
The link interface consolidates the rcspo>QSes and works through the appropriate algorithms to thereafter send responses or controls to the relevant switch, base station, or other subnet controller.
For example, a request to establish a high speed tunnel between two network entities involves the following event flow:
The link interface receives and deciphers the request, chooses the high speed tunnel set np procedure, and sends requests to the:
subscriber authentication server to see if the subscriber is legitimate;
1 S subscn'ber management server to see if the subscn'ber account is up to-date and to get information on the level of service and settings of features;
policy server to determine the rules and boundaries of the tunnel to be set up (i.e., how the tunnel should be set up);
address binding servez~to set up the address binding between the requested two paints; and OAM&P and billing to begin recording the billing information.
'fhe link interface consolidates the responses and goes through the tunneling set up algorithm and sends controls to the switches on the path of the request to identify two points to establish the tunnel.
After receiving aclmowlegcmcnt from all the involved network entities, the link interface sends a response tv the requester indicating that the hid spend tunnel is established as weU as indicating the tunnel (path) information.

~~;~P1~?~1 Slf

Claims

1. A fixed wireless point-to-multipoint network for providing seamless communication coverage to a plurality of subscribers, characterised by:
a plurality of base stations for providing wireless access to said subscribers;
each base station having connectivity to one another on a first network layer via at least one of a number of switches; and each of the switches having connectivity to one another over a second network layer via a transport thereby enabling one user to communicate directly with another user in said first network layer via one of said switches.

2. A network as in claim 1, further characterised by a subnet controller configured to provide information and fictions; and intelligent customer premise equipment configured to cooperate with the information and functions provided by the subnet controller to make available to a subscriber a capability of dictating when and how much bandwidth is required.

3. A network as in claim 1, further characterised by a subnet controller configured to provide information and functions; and direct connection tunneling established by the information and functions provided by the subnet controller whereby the network routing efficiency improves and network costs reduce.

4. A network as in claim 1, characterised in that the switches are Integrated Data Centric Network IDCN switches.

5. A point-to-multipoint wireless distribution network, characterised by:
a plurality of base stations and a plurality of switches;
a first network layer and a second network layer; and a transport, each of the base stations having connectivity to one another on the first network layer via at least one of the switches, each of the switches having connectivity to ant another ours the second network layer via the transport, the transport representing any one of a ring architecture, a star architecture and a hybrid ring, star and mesh architecture.

6. A network as in claim 5, characterised in that the switches are Integrated Data Centric Network IDCN switches.

7. A network as in claim. 6, characterised in that each of the base stations having digital and microwave equipment adapted to route any one of asynchronous transfer mode (ATM) cells and Internet protocol (IP) packets either to appropriate modulators or to appropriate demodulators and thereafter route back to the network.

8. A network as in claim 7, characterised in that the digital and microwave equipment includes both video network to wireless transmission equipment, microwave transmitters, receivers, and antennae.

9. A network as in claim 6, characterised in that each of the base stations have Frequency division multiple access and time division multiple access.

10. A network as in claim 9, further characterised by a layered hierarchy network architecture, the first and second network layers being part of the architecture and being supported by the plurality of switches connected in a ring, star and mesh configuration.

11. A network as is claim 5, characterised in that the second network layer is configured to access each of an Integrated Digital Centric Network IDCN, Internet protocol (IP) network, frame relay network or a public switch transfer network (PSTN) via a telephony gateway.

12. A network as in claim 5, characterised in that the transport and a local area network are arranged between the base stations and have connectivity to Integrated Digital Centric Network IDCN switches and are within the second layer.

13. A network as in claim 5, characterised in that the second network layer is configured and arranged to provide access via a telephony gateway to at least one further network.

14. A method of communication through a point-to-multipoint wireless distribution network, characterised by:
providing wireless access to subscribers via a plurality of base stations and a plurality of switches;
providing each of the base stations with connectivity to one another on a first network layer via at least one of the switches;
providing each of the switches with connectivity to one another over a second network layer via a transport, the transport representing any one of a ring architecture, star architecture and hybrid ring, star and mesh architecture;
and communicating between subscribers directly in either the first network layer or externally of the first network layer via at least one of the switches.

15. A method as in claim 14, characterised in that the switches are integrated Digital Centric Network IDCN switches.

16. A method as in claim 14, characterised in that the communicating is carried out from providing seamless communication coverage to a plurality of the subscribers as a result of all of the providing steps.

17. A method as in claim 14, further characterised by integrating voice, data and video services into the first and second layers.