Traffic engineering system on multi-protocol label switching network using DTM technology

The Related Concept

The invention is called DIP-TE (Dtm IP-Traffic Engineering) and is a traffic engineering mechanism running over a conventional IP network such as multi-protocol label switching. Normally the conventional network is responsible for the traffic engineering, DIP-TE takes over this responsibility by use of DTM (Dynamic Synchronous Transfer Mode) technology.

Background of the Invention

RSVP-TE (Resource Reservation Protocol - Traffic Engineering) used normally and broadly used in MPLS (Multi Protocol Label Switching) does not guarantee bandwidth and delay or protection against high RTD. For that reason, it may not be reliable when transmitting real time sensitive traffic. Even when FRR (Fast ReRoute) is used, a delay time and package loss may occur. As an addition OPEX of RSVP-TE is very high in MPLS. There is no OPEX when DIP-TE is used over conventional networks such as an MPLS network.

As shown in Figure 1 , hop by hop routing configuration is a requirement when applying traffic engineering within current and conventional networks. At each stage of the traffic flow from MPLS router (2) on Point A (A) to MPLS router (2) on Point B (B) through arriving at other MPLS routers (2) of the traffic flow should be manually configured at each stage and this is called traffic engineering.

As a result, due to above described disadvantages and inadequacy of existing solutions it has been necessary to make development in the related art.

Purpose of the Invention

Differently from the existing related concept, the invention aims to disclose an embodiment offering new solutions in this field and having different technical characteristics. Primary purpose of the invention is to provide a functional DIP-TE application of Traffic Engineering model basis achieved by use of DTM technology and running on conventional platforms such as multi-protocol label switching network.

Another purpose of the invention is to provide a secure base for real time sensitive traffic proceeding as well as secure traffic.

A further purpose of the invention is to provide protection against delay or high RTD.

Another purpose of the invention is to transfer RSVP-TE to an upper layer instead of over the commonly used MLPS network. By doing this a simple and cost effective solutions is offered.

Transfer network and switching solution used in the proposed structure is to use DIP-TE with DTM. DTM is a fast circuit switching technology. It is simple convenient low cost and considerably safe and has high QoS performance (DiffServ strict). 100 % Hittless connection is guaranteed by use of double road StrictServ when used with DIP-TE.

The structural and characteristics features of the invention and all advantages will be understood better in detailed descriptions with the figures given below and with reference to the figures, and therefore, the assessment should be made taking into account the said figures and detailed explanations.

Brief Description of the Drawings

Figure 1 is general view of RSVP-TE system of the related art.

Figure 2 is general view of DIP-TE system of the invention.

The drawings are not necessarily to be scaled and the details not necessary for understanding the present invention might have been neglected. In addition, the components which are equivalent to great extent at least or have equivalent functions at least have been assigned the same number.

Description of Part References

1 . DIP-TE system 2. MPLS router

3. LSP path

4. Virtual circuit

5. DTM router

A: Point A

B: Point B

C: Point C

Description of Abbreviations

MPLS: Multi Protocol Label Switching

DTM: Dynamic Synchronous Transfer Mode

TE: Traffic Engineering

DIP-TE: DtmlP Traffic Engineering

RSVP-TE: Resource Reservation Protocol - Traffic Engineering

OPEX: Operating Expense

FRR: Fast Reroute

QoS: Quality of Service

KBPS: Kilobit Per Second

LSP: Label Switched Path

FEC: Forward Equivalent Class

CBR: Constant Bit Rate

VBR: Variable Bit Rate

VC: Virtual Circuit

Detailed Description of the Invention

In this detailed description, the preferred embodiments of DIP-TE system (1 ) being subject of this invention have been disclosed solely for the purpose of better understanding of the subject and described in a manner not causing any restrictive effect.

The invention relates to a functional DIP-TE system (1 ) of Traffic Engineering model basis achieved by use of DTM technology and running on multi-protocol label switching network.

DIP-TE system (1 ) disclosed under the invention uses DTM technology guaranteeing deterministic delay transmission, low jitter (minimum sampling algorithm), bandwidth directly proportional to number of slots on the channel, low loss rate and non-random medium access.

DIP-TE system (1 ) consists of MLPS router (2) used for connection routing operations in MPLS network and LSP path (3) providing data transmission in MPLS network.

DIP-TE system (1 ) contains virtual circuit (4) connected to terminal arrival points by use of various paths and providing performance of traffic engineering independent of any IP based system and DTM router (5) providing use of DTM technology and creation of virtual circuits (4).

DIP-TE system (1 ) is based on sharing sources (buffer memory and bandwidth) and therefore, it is concerned with not separation of dynamic but marking the packages.

Core network does not have RSVP message processing or state storage processes. Because DTM technology provides a deterministic delay, low jitter and assured bandwidth during lifetime of the channel.

DTM is a technology based on high speed circuit switching structure and contains dynamic re-allocation of bandwidth. The DTM technology provides multicast services, channels with varied bit-rates (from 512 Kbps until the capacity of the medium) and low time of circuit configuration (few milliseconds). It can be used as an end-to-end solution or as a transport of protocols like ATM and IP. In DTM technology switching is synchronized. At each hop, there is an average constant switching delay of 125 ms. Processing control data occurs only in channel installation and disconnection phases. Switches have queries only in case of time synchronization between data paths. For that reason, congestion and overflow problems are not encountered.

Use of DTM’s such features on MPLS network provides creation of extremely stable VC(virtual circuits) (4) from Point A (A) to Point B (B). When a virtual circuit (4) is established from point A (A) to Point B (B) on MPLS network, one the shortest LSP path (3) will be created and all traffic to one target will use same FEC as long as virtual circuit (4) is active.

DTM is a fast switching which guarantees delay time, a little stress, traffic isolation and flexible resource reservation. DTM only provides traditional CBR service. It facilitates a flexible and easy interaction with the IETF IntServ and Diffserv QoS models while it provides other services such as VBR at IP control level. Communication society think that the future is the IP applications on top of physical transport lines such as SDH/SONET but some difficulties such as static hierarchical structure are still in need of solution. IP/MPLSTM architecture is more convenient for broad networks such as core internet in terms of flexibility, scalability and manageability.

What is offered and proposed in the DIP-TE system (1 ) disclosed under this invention is IP/DTM: DTM technology executes quick forwarding of packages by time switching slots automatically, MPLS network only provides LSP, LDP and VPN Services and has no other functionality on this architecture. Just like any circuit switching technology, DTM technology isolates traffic of each circuit. This means that effectiveness of each circuit does not affect the other. The fact that DTM switching is synchronous facilitates a transmission of quality and constant transmission rate. Thus RSVP-TE functionality performed in MPLS network can be performed in DTM layer.

In DIP-TE system (1 ) of the invention, RSVP-TE and FRR function is transferred to a next upper level and higher traffic protection is provided and guaranteed QoS and bandwidth is offered.

Normal RSVP traffic engineering would have to be built from Point A (A) to Point B (B) in all MPLS network. With DIP-TE System (1 ) of the invention, thanks to overlapping network function created by DTM routers (5), only two different virtual circuits (4) are opened.

In DIP-TE system (1 ) normal MPLS function over MPLS routers (2) LSP path (3) will be created automatically. In DIP-TE system (1 ) instead of execution of all virtual circuits (4) manually, protection route virtual circuits (4) automation can be performed.

As explained before, total 3 virtual circuits (4) are needed to be created in order to provide a protected connection between Point A (A) and Point B (B). They are:

- direct virtual circuit (4) connection from Point A (A) to Point B (B),

- virtual circuit (4) connection from Point A (A) to DTM router (5) located at various paths and

- connection to DTM router (5) from DTM routers (5) located at various paths to Point B (B). Colour determination runs algorithm mechanism and DTM routers (5) located in different area are included in zone’s colour layer.

In the example, Turkey can be divided into 12 regions, 81 cities, and neighbourhoods to determine the part of city can be chosen subject to size of the cities. For instance, Istanbul is used as city and Anatolia Side is used as neighbourhood, and is selected as Point A(A). Location parameters of DTM router (5) is Mavi34.20 (Blue34.02). Blue represents region, 34 stands for city and 02 indicates neighbourhoods. Ankara is used as city and Centre as neighborhood and is determined as Point B (B). Location parameters of DTM router (5) is Kirmizi06.01 (Red06.01 ). Red represents region, 06 stands for city and 01 indicates neighborhood.

A road selection should be made in the software to activate the automation process of protection connection. DTM routers (5) and all locations being metrics are recognized by the DIP-TE system (1 ).

If the connection from Blue to Red (from Point A (A) to Point B (B) is main connection, connection from Blue to Red is not used as protection connection again. Protection connection can only be selected among other regions having a different metric. There are 9 regions and therefore nine colours remaining for selection. Each of all DTM routers (5) knows the use and connection information of others. Among remaining nine colours, the DTM router (5) having the biggest connection capacity and the least use is selected.

In the example, Izmir is used as city and centre as neighbourhood and is determined as Point C (C). Location parameters of DTM router (5) is San06.01 (Yellow35.01 ). Yellow represents region, 35 stands for city and 01 indicates neighbourhood.

The information such as connection speed of DTM routers (5), whether or not there is a use in the data area and it is in idle position are monitored. The connection between Istanbul and Izmir DTM routers (5) is 10 Gbps, no use in the data area is monitored and router D(5) at Point C (C) is in idle status. Therefore, as shown in the figure, DTM router (5) at Point C (C) is selected to create a virtual circuit (4) from Blue34.02 (point A (A)) to Yellow35.01 (Point C (C)). In other words, a virtual circuit (4) is opened between Point A (A) and Point C (C). Then the software firstly determines the use from Point C (C) to Point B (B) in order to complete the connection desired to be made from Point A (A) to Point B (B) and complete the performed protection connection from Point A (A) to Point C (C), and other virtual circuit (4) between Point C (C) and Point B (B) is opened. Thus only two virtual circuits (4) are created.