Ibrahim T. Okumus

A scalable model for interbandwidth broker resource reservation and provisioning

As the Internet evolves into global communication and commercial infrastructure, the need for quality-of-services (QoSs) in the Internet becomes more and more important. With a bandwidth broker (BB) support in each administrative domain, differentiated services (Diffserv) is seen as a key technology for achieving QoS guarantees in a scalable, efficient, and deployable manner in the Internet. In this paper, we present a scalable model for inter-BB resource reservation and provisioning. Our BB uses centralized network state maintenance and pipe-based intradomain resource management schemes that significantly reduce admission control time and minimize scalability problems present in prior research. For inter-BB communication, we design and implement a BB resource reservation and provisioning protocol (BBRP). BBRP performs destination-based aggregated resource reservation based on bilateral service level agreements (SLAs) between peer-BBs. BBRP significantly reduces the BB and border routers state scalability problem by maintaining reservation state based only on destination region. It minimizes inter-BB signaling scalability by using aggregated type resource reservation and provisioning. Both analytical and experimental results verify the BBRP achievements.

Inter-domain LSP setup using bandwidth management points

Bandwidth management points (BMP) are a necessity to manage the intra and inter-domain resources in the Internet. We propose a way to setup inter-domain label switched path (LSP) with the help of a BMP in a multiprotocol label switching (MPLS) over the Diffserv network. We use extended simple inter-domain bandwidth broker signalling protocol (SIBBS) to distribute the labels inter-domain. We also use a BMP to interact with the MPLS to setup the intra-domain LSP and to provision the intra-domain traffic. With the help of a BMP, we show how end-to-end quality of service (QoS) can be achieved.

Inter-domain QoS routing on Diffserv networks: a region-based approach

Quality of Service (QoS) routing is inherently a difficult problem. Inter-domain QoS routing is even harder, because it involves entities residing in distinct administrative domains. There are two problems that need to be solved in inter-domain QoS routing: topology distribution in a scalable fashion and finding paths that satisfy QoS constraints and provide connectivity. In this paper we present region-based, link-state, source-specified, inter-domain QoS routing architecture that addresses these questions. Our architecture is scalable and does not suffer from the problems caused by hierarchical routing. Analysis results show that the average region size and the average shortest path length (SPL) are inversely proportional and scalability of the approach increases as the region size decreases. Gain from the scalability is far more than the loss from the average SPL, especially with larger topologies.

An implementation study of a dynamic inter-domain bandwidth management platform in DiffServ networks

In this paper, we assess the scalability and efficiency of a scalable bandwidth management point (BMP) for guaranteed quality-of-service in DiffServ networks. Our BMP uses centralized network state maintenance and pipe-based intra-domain resource management schemes that significantly reduce the admission control time and minimize the scalability problems present in prior research. We have designed, developed and implemented an enhanced Simple Inter-Domain Bandwidth Broker Signaling (SIBBS) protocol for inter-domain communication. The BMP uses dynamic inter-domain pipes to handle inter-domain provisioning and dynamic provisioning schemes to increase signaling scalability. To assess our BMP implementation in terms of signaling scalability and effective resource utilization, we conducted experiments on a test-bed demonstrating how a BMP substantially increases resource utilization and scalability while requiring minimum changes in the underlying infrastructure.

A bandwidth-broker based inter-domain SLA negotiation

This work presents an Inter-Domain Bandwidth Broker (BB) based Service Level Agreements (SLAs) Negotiation Model for Differentiated Services (DiffServ) networks. A BB in each DiffServ domain handles SLAs on behalf of its domain by communicating with its neighboring peers. The proposed model uses a destination-based SLAs aggregation to increase signaling and state scalability, and it uses a BB-based inter-domain routing to increase resource utilization. The experimental results are provided to verify the achievements.

Scalability of inter-domain edge tunnels using bandwidth brokers: a region-based approach

In this paper we present a scalability study on inter-domain tunnels using bandwidth brokers. Our approach is based on collections of autonomous systems called regions. We analyzed our architecture through simulation. Our analysis results show that scalability of the approach depends on the size of the regions, and as the size of the region decreases, scalability of the approach increases. We show that our architecture increases state scalability as well as signaling scalability for Diffserv networks.

Design and implementation of a Secure Bandwidth Broker Discovery Protocol

Differentiated Services architecture definition lacks control level functionalities. One of the solutions proposed to fill this gap is Bandwidth Brokers (BB). Bandwidth Brokers are autonomous entities inside a network which is responsible for bandwidth management of the network along with other tasks. There is a lack of protocol for Bandwidth Brokers to discover other Bandwidth Brokers automatically. This study introduces a new Secure Bandwidth Broker Discovery Protocol (BBDP), which allows Bandwidth Brokers to automatically discover other Bandwidth Brokers. In this paper design principles, protocol details, working scenarios and implementation details of the BBDP protocol are presented.

A scalable and efficient inter-domain QoS routing architecture for DiffServ networks

With bandwidth broker (BB) support in each domain, differentiated services (DiffServ) is seen as a key technology for achieving QoS guarantees in a scalable, efficient, and deployable manner in the Internet. We present a route server (RS) architecture that is compatible with the BB model for inter-domain QoS routing. The RS is responsible for determining QoS routes on behalf of all the routers and for exchanging routing information with its neighboring peers. It optimizes network resources by taking the intra-domain resource utilization state into account for selecting a route. It also achieves scalability by precomputing a limited number of paths for each destination region and mapping all the packets to one of these paths regardless of their sources.