Evolution of Spanning Tree Protocol: From STP to SPB and Trill – A Comparative Analysis

Metro Ethernet is taking off rapidly as a WAN service and the simplicity, ubiquity, and plug-and-play features of Ethernet are some key success factors. The original bridging methods assumed the use of VLANs and spanning tree protocols within provider bridge (PB) and provider backbone bridge (PBB) networks. Because of the inadequacy of the existing spanning tree protocols to support carrier network requirements, very recently, a new class of shortest path routing solutions have been introduced that avoid the use of spanning tree protocols in the core namely, shortest path bridging (SPB). This paper aims at illustrating that we can still use spanning trees in metro ethernet provided that the tree generation and VLAN-spanning-tree mapping are performed adequately. We call our solution smart spanning tree bridging (SSTB). SSTB can be used to enhance the 802.1s MSTP, without requiring significant changes in the current Ethernet equipment. Using very simple but yet realistic numerical examples, we show that SSTB yields near optimal bandwidth and link usage. We also show that SSTB outperforms SPB in terms of service delivery, frame loss and jitter, while being comparable in terms of bandwidth usage and latency. Further, SSTB requires only a couple of spanning tree instances, significantly reducing processing and complexity of bridged networks.

Data center networks (DCNs) are at the forefront of a radical transformation, fueled by the rapid rise of artificial intelligence (AI), cloud-native adoption, and enterprise digitalization, which together place unprecedented demands on their design and performance. From healthcare AI and intelligent transportation to business analytics, modern DCNs are expected to support a diverse and evolving mix of bandwidth-demanding applications, each with distinct quality of service (QoS) requirements. Yet, most state-of-the-art DCN solutions rely on oversimplified DCN data traffic models, failing to address the required application-level differentiation in terms of end-to-end (E2E) latency demands. In response, we propose ALAS-DCN, a novel, to our knowledge, application-aware, low-latency, scalable DCN architecture, based on optical packet switching in the intra-rack and inter-rack domains that is both designed and rigorously evaluated using commercial QoS specifications and realistic traffic patterns of different applications coexisting within the same DCN. ALAS-DCN integrates three hierarchical optical sub-networks: intra-rack, inter-rack, and bridge, each governed by a custom wavelength division multiplexing (WDM) medium access control (MAC) protocol that dynamically prioritizes critical traffic packets, according to the specific application E2E latency demands. Unlike prior approaches, our evaluation leverages realistic workload traces generated by established traffic generators, capturing the application diversity within modern data center (DC) environments. Extensive experimental simulations across five representative DC categories, each hosting a different mix of modern applications, demonstrate that ALAS-DCN consistently achieves up to 95% throughput efficiency and sub-µs latency for high priority traffic across a variety of applications, consistently meeting their differentiated latency constraints. Scalable up to 20,000 servers, ALAS-DCN redefines the DCN as not just a transport layer but an intelligent enabler of next-generation application performance.

Ethernet networks using rapid spanning tree protocol (RSTP) to ensure a loop-free topology and provide redundant links as backup paths in case an active link has failed. However, when a failure occurs, RSTP requires a significant amount of reconfiguration time in order to find an alternative path. RSTP is also limited by the number of nodes in a ring network, and its performance degrades when the number of nodes increases. In this paper, we introduce a new approach, called loop prevention and load balancing (LPLB), which can be applied to Ethernet ring networks. If failure occurs, LPLB only requires a very short amount of time to switch to an alternative path and in most cases; LPLB needs zero recovery time for that switching. In addition, under most situations, no data frames are lost when a node switches to an alternative path. Unlike RSTP and the media redundancy protocol (MRP), LPLB also provides load balancing among network links that in turn improves the network performance and reduces the probability of bottleneck occurrence.

Chapter 15 - Cloud Computing Data Center Networking

The proposed Internet paradigm The Flying Ad Hoc Network (FANET), Named Data Network (NDN), and Software Defined Network (SDN) have attracted the interest of the scientific community. The TCP/IP protocol is the present Internet standard, while NDN is the future internet architecture that builds on it. Data availability is improved via NDN, which substitutes named data for the nodes' addresses. SDN is a good option for communicating effectively, utilizing resources effectively, and supporting developing technologies. The SDN has attracted interest because of its high-level programmability and flexibility. Numerous applications in the military, business, and civil sectors make extensive use of FANE T. The broadcast characteristic of NDN causes an issue known as a broadcast storm in dense FANET environments. The issue is caused by duplicate packets, which raises the overall amount of traffic and retransmissions. FANET has a problem with the timely and quick transmission of essential packets. In this paper, we suggested a new scheme named "Novel Adaptive Broadcast Storm Avoidance (NABA)" for SDN and NDN-enabled FANET, which uses a controller to lessen the broadcast issue. Our scheme made use of the SDN controller's effective flow management to regulate the broadcast storm and facilitate packet transfers. Additionally, we divided up the packet into categories based on priority. The priority of the packet is determined by the naming criterion. In terms of the overall number of Interests and content retrieval time, the findings show that NAB A performs better than native NDN floods.

Middleboxes have become an integral part of modern enterprise and data center networks. They are used for realizing various performance and security objectives. Most middlboxes (e.g., firewalls, Intrusion Detection Systems (IDSs), Network Address Translators (NATs), etc.) are dedicated hardware appliances. However, recent advancements in cloud and virtualization technologies have fueled the concept of Virtual Middleboxes or Virtual Network Functions (VNFs) along with a new research field known as Network Function Virtualization (NFV). This area of research has gained a lot of traction from both industry and academia. Although much progress has been made in NFV technology, a crucial component for realizing the primary objective of NFV is still missing – a management and orchestration [7] system that conforms to the principles of NFV: open source, open API and standardized software solutions. Without this feature, network operators may end-up with the same situation of vendor lock-in as with proprietary hardware middleboxes. A number of recent proposals like Stratos [8], OpenNF [9], and Split/Merge [10], strive to fulfill the requirements for VNF management and orchestration. However, they propose incompatible northbound APIs. What is really needed is a standardized API that is flexible enough to express a wide range of NFV management and orchestration operations. History shows that standardization efforts usually take a long time and often are futile. Hence, we take a different approach, and propose to use an existing, well known, standardized interface for NFV management and orchestration: the Linux file system interface.

Conventional Ethernet protocols struggle to meet the scalability and performance requirements of data centers. Viable replacements have been proposed for Data Center Ethernet (DCE): link-layer multipathing (MP) is deployed to replace Spanning Tree Protocol (STP) and thus improves network throughput; end-to-end link-layer congestion control (CC) is proposed to better guarantee loss-free frame delivery for Ethernet. However, little work has been done to incorporate MP and CC to offer a more comprehensive solution for DCE. In this paper, we propose a two-tier solution by integrating our Dynamic Load Balancing MultiPath (DLBMP) scheme with CC. Instead of using two separate parameters, i.e. path load and buffer level, to trigger MP and CC, our solution only needs to monitor path load metric to manage MP and CC in an integrated way. Different from a pure CC mechanism, which generates notifications from network core, our integrated CC can make use of link load information in edge switches which directly inform sources to control traffic admission. To minimize overhead and accelerate update, Software-Defined Networking (SDN) techniques are employed in our implementation, which decouples routing intelligence from data transmission. Hence, data sources can react more rapidly to congestions and network can be guaranteed with loss-free delivery. In addition, our MP scheme is further improved by introducing application-layer flow differentiation. With such a fine flow differentiation (FFD) mechanism, traffic can be more evenly distributed along multipaths, resulting in better bandwidth utilization. Simulation results show that our combined solution can further improve network throughput with FFD mechanism and guarantee loss-free delivery with integrated CC.

Parallel construction of multiple independent spanning trees on highly scalable datacenter networks

Software Defined Network (SDN) is getting popularity both from academic and industry. Lot of researches have been made to combine SDN with future Internet paradigms to manage and control networks efficiently. SDN provides better management and control in a network through decoupling of data and control plane. Named Data Networking (NDN) is a future Internet technique with aim to replace IPv4 addressing problems. In NDN, communication between different nodes done on the basis of content names rather than IP addresses. Vehicular Ad-hoc Network (VANET) is a subtype of MANET which is also considered as a hot area for future applications. Different vehicles communicate with each other to form a network known as VANET. Communication between VANET can be done in two ways (i) Vehicle to Vehicle (V2V) (ii) Vehicle to Infrastructure (V2I). Combination of SDN and NDN techniques in future Internet can solve lot of problems which were hard to answer by considering a single technique. Security in VANET is always challenging due to unstable topology of VANET. In this paper, we merge future Internet techniques and propose a new scheme to answer timing attack problem in VANETs named as Timing Attack Prevention (TAP) protocol. Proposed scheme is evaluated through simulations which shows the superiority of proposed protocol regarding detection and mitigation of attacker vehicles as compared to normal timing attack scenario in NDN based VANET.

Software Defined Networking (SDN) is the more reliable and flexible networking architecture. Due to its programmable nature, it is getting more popular in every research domain of Computing. Moreover, Named Data Networking (NDN) architecture is also more beneficial and emerging technology of Internet. NDN focuses on the content name instead of its location and replaces the usage of IP addresses. Lot of research has been made to integrate SDN and NDN due to their benefits of better management-ability, flexibility, less complexity, centralized control, decoupled control and data planes etc. Mobile Ad Hoc Network (MANET) is also getting more popular due to huge advancement in Mobile communication devices. Combining SDN and NDN in MANET will resolve lots of problems (i.e. forwarding, mobility, management etc.) which are difficult to tackle with single architecture. Broadcast Storm is always a challenging issue in Ad Hoc networks like MANET. In this paper, we proposed a Controller based Selective Forwarding (CSF) scheme by merging SDN, NDN and MANET to overcome the Broadcast Storm Problem (BSP) and other issues caused by BSP. CSF is evaluated using different simulation parameters which shows superiority over the Native ND-MANET in reference to BSP.

A survey on architectures and energy efficiency in Data Center Networks

Named Data Networking (NDN) has emerged as a promising information-centric networking paradigm that addresses the limitations of the traditional IP-based Internet architecture. The core principle of NDN relies on content naming instead of host addressing, to provide efficient, secure, and scalable content delivery. Routing is a critical component of NDN and is responsible for discovering and maintaining optimal paths to named content. This paper presents a comprehensive review of routing techniques in NDN, focusing on the design principles, algorithms, and performance metrics, especially in wired network architecture. We first summarize the NDN architecture and discuss its key components. We then delve into the fundamental routing concepts in NDN and categorize and examine various routing techniques, including link state, distance vector, and centralized approaches based on Software Defined Network. We also summarize the relevant research efforts proposed to address NDN routing challenges by focusing more on wired network architecture. Finally, we identify open research issues and future directions in NDN routing, emphasizing the need for scalable, efficient, and secure routing techniques that can fulfill the growing demands of the modern Internet. In conclusion, this review serves as a valuable reference for researchers and practitioners in NDN, offering a comprehensive understanding of the current state-of-the-art routing techniques, limitations, and potential future advancements.

This study proposes an autonomous distributed control method for single link failure based on loops in a network. This method focuses on the concept of tie-sets defined by graph theory in order to divide a network into a string of logical loops. A tie-set denotes a set of links that constitutes a loop. Based on theoretical rationale of graph theory, a string of tie-sets that cover all the nodes and links can be created by using a tree, even in an intricately-intertwined mesh network. If tie-sets are used as local management units, high-speed and stable fail-over can be realized by taking full advantage of ring-based restoration. This paper first introduces the notion of tie-sets, and then describes the distributed algorithms for link failure. Experiments are conducted against Rapid Spanning Tree Protocol (RSTP), which is generally used for fault recovery in mesh topological networks. Experimental results comparing the proposed method with RSTP suggest that our method alleviates the adverse effects of link failure with a modest increase in state information of a node.

A major recent development in computer networking is the emergence of Software Defi ned Networking (SDN), whose goal is to provide a centralized, programmable control plane that is decoupled from the distributed data planes on individual network devices. In particular, the development of OpenFlow has demonstrated many potential benefits of SDN, and multiple vendors have started to offer commercial switches supporting the OpenFlow standard. Researchers have also made progress on SDN components including SDN controllers, switches, programming interfaces, verification and debugging tools, and SDN applications in data center networks and campus networks. Despite the progress, many important issues regarding SDN remain. The goal of this Special Topic Issue is to explore research and developments related to SDN to further its state of art.

Software Defined Networking (SDN) and Named-Data Networking (NDN) are two new paradigms that aim at changing the way we design and architect computer networks. The NDN architecture was first proposed to solve the problems of current Internet Protocol (IP) communication. However, there is an important disadvantages in the existing NDN, which are the very large size of the NDN forwarding table and the huge overhead cost of the forwarding process. This may result in not only a slow delivery of data, but also in a lot of network traffics. For this reason, this architecture cannot be appropriately used in a large-scale network.To solve this problem, we proposed a novel forwarding Strategy for Named Data Networking based on SDN and bloom Filter (NDN-SF) in order to improve the efficiency of content delivery and enhance the consumption of network resources. Our experimental results showed that latency and bandwidth consumption are reasonably low in our method NDN-SF. They also demonstrated that the developed scheme is more efficient than the existing forwarding strategies in NDN.