An order entry system communicates with the customer over a user interface and at the same time works with an automated installation system for installing network service. The communication with the customer can be accomplished over the world wide web. The customer goes to the network provider's web site and signs on to gain access to the order entry system. The order entry system than conducts a conversation with the customer who is requesting service, and the order entry system conducts a conversation with the automated installation system that is installing the service. The order entry performs the tasks of prompting the customer to place a new service order. The service parameters of the new service order are passed to the installation system. The installation system responds to the order entry system with a route, i.e. capacity available on the network, or no route. The order entry system notifies the customer of the route and prompts the customer to add a service order for the route to the customer order. If the customer adds the service order to the customer order, the order entry system prompts the customer to reserve the service order or to submit an order for the service. If the customer reserves or submits an order for the service, the order entry system request the installation system to design an actual communication line circuit to satisfy the order. The installation system rechecks that there is capacity for the route, assigns and validates the communication line, and completes the design for the communication line circuit. Lastly, the installation returns a reserved status along with detailed information about the circuit. The order entry system informs the customer that the communication line is reserved. This occurs within minutes of requesting the reservation, and the customer can access detail information about network components of the communication line circuit if desired.

Order entry system for telecommunications network service

High-speed packet networks will begin to support services that need Quality-of-Service (QoS) guarantees. Guaranteeing QoS typically translates to reserving resources for the duration of a call. We propose a state-dependent routing scheme that builds on any base state-independent routing scheme, by routing flows which are blocked on their primary paths (as selected by the state-independent scheme) onto alternate paths in a manner that is guaranteed—under certain Poisson assumptions— to improve on the performance of the base state-independent scheme. Our scheme only requires each node to have state information of those links that are incident on it. Such a scheme is of value when either the base state-independent scheme is already in place and a complete overhaul of the routing algorithm is undesirable, or when the state (reserved flows) of a link changes fast enough that the timely update of state information is infeasible to all possible call-originators. The performance improvements due to our controlled alternate routing scheme are borne out from simulations conducted on a fully-connected 4-node network, as well as on a sparsely-connected 12-node network modeled on the NSFNet T3 Backbone.

Controlling alternate routing in general-mesh packet flow networks

Several congestion control methods for asynchronous transfer mode (ATM,) networks that support multimedia traffic by providing different guaranteed quality for each class of traffic are discussed. The two categories of congestion control methods presented are preventive congestive control and reactive congestive control. Preventive congestion control takes any action necessary to prevent congestion Reactive congestion control is responsible for any necessary action to recover from a congested situation, A summary of a proposed multilevel control scheme is also presented. >

Congestion control methods for BISDN

A system for automated installation of a communication line using an optimal route between a source location and a destination location is disclosed. The system includes a routing engine providing an automated design process for rendering the optimal route. The routing engine utilizes a routing algorithm to select the optimal route from a graph of capacity links defining a plurality of possible routes between the source and destination locations. If, at any time during the design process, the optimal route or capacity links defining the optimal route are detected as unavailable for any reason, the routing engine re-initiates the design process and thereafter selects a new optimal route based upon a new capacity graph built without the previously unavailable capacity link. Once designed, the available optimal route is provided to a command and control engine, which, in turn, manages the installation of the communication line using the optimal route. The command and control engine manages the process for assigning the optimal route in the provisioning system.

Routing engine for telecommunications network

The unprecedented growth of IP traffic is leading Internet service providers and network operators worldwide to investigate architectural alternatives for cost effective, reliable, scalable, and flexible multiterabit IP backbones. In this paper, several overlay, service, and transport layer networking architectures, which employ IP, MPLS, SONET/SDH, and DWDM technologies, are proposed and analyzed. Multiple parameters, such as network capacity, cost, restoration strategy, reconfigurability, and accommodation of preemptable traffic, are considered for the architectural comparison. Detailed network design and economic analysis are provided for the different alternatives considering a typical nationwide U.S. backbone with projected IP traffic in approximately three years. Several sensitivity analysis results are also shown, to evaluate the effect of cost changes in some of the critical technological factors in these architectures, such as 10 Gb/s optics cost or IP router cost. The results show the value of transport layer networking architectures for multiterabit IP backbones, and how, when compared to service layer architectures, they provide additional desirable features such as wavelength reconfigurability and restoration scalability.

Analysis and design of backbone architecture alternatives for IP optical networking

We describe a new integrated network design tool (INDT) being developed in AT&T Bell Labs. This tool includes a variety of network design algorithms that encompass virtually every modern network design scenario. INDT is intended for designing private line networks, switched voice networks, integrated private line and switched voice networks and integrated ATM based multimedia networks. All these versions come in two flavors: (i) a desert start version that designs unconstrained networks assuming no embedded base and (ii) a constrained version that takes the embedded network base as input and produces a constrained optimal network design that allows maximum reuse of the embedded network.

Overview of INDT-a new tool for next generation network design

A congestion control scheme based on alternate routing for connectionless high-speed data networks is presented. In this scheme, if a trunk in the primary path is congested, then a portion of the traffic intended for that trunk is offered to a secondary trunk. The primary path is the shortest distance path in hop count, while the secondary path is at least one hop more than the shortest path. A key innovation is an algorithm for distributed computation of secondary paths which are guaranteed to be loop-free. The secondary trunk accepts the alternate-routed traffic only if it is uncongested. The alternate-routed traffic is given lower loss priority by the trunks along the secondary path so that the primary traffic carried by these trunks does not suffer significant performance degradation. Performance results show that alternate routing affords at least an order-of-magnitude improvement in end-to-end packet blocking under sustained focused overload. The utility of this scheme is demonstrated in the context of IEEE 802.6 networks. >

Congestion control for connectionless networks via alternate routing

The author describes a novel approach to the design of node-by-node routing virtual circuit data networks. A major challenge in the design of such networks is to ensure that the network has loop-free alternate routing. The approach explicitly integrates the loop-free alternate routing requirements into the network design process and produces loop-free cost optimized networks. This is achieved by identifying a topology which supports loop-free alternate routing. This topology is optimal in the sense of achieving a prescribed level of network connectivity with the fewest possible links. This topology have several desirable routing properties, based on which a simple loop-free alternate routing scheme has been developed. Further, by solving an optimization problem, it is possible to find the optimal connectivity between nodes that minimizes the total link length. This leads to a significant reduction in network cost. Two methods for solving this optimization problem have been developed. >

http://ieeexplore.ieee.org/iel2/808/2325/00064186.pdf

P. Harshavardhana

Papers

Overview of INDT-a new tool for next generation network design

Congestion control for connectionless networks via alternate routing

Design analysis of nonhierarchical node-by-node routing virtual circuit networks