DOCSLIB.ORG

Is-Is Protocol Model Suite: Simulation of Implemented Features and Their Configuration

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Is-Is Protocol Model Suite: Simulation of Implemented Features and Their Configuration International Journal of Innovative Technology and Exploring Engineering (IJITEE) ISSN: 2278-3075, Volume-8 Issue-8, June 2019 Is-Is Protocol Model Suite: Simulation of Implemented Features and Their Configuration. Arif Sari, Joshua Chibuike Sopuru, ÖnderOnursal Abstract: In recent times, the Intermediate System to This is widely known as Integrated IS-IS and was also Intermediate System (IS-IS) protocol gains more attention from specified in RFC 1195. One major importance of the IS-IS is network administrators and users alike. As many service its ability to engage large networks yet following the providers engage in the active usage of this protocol, the IS-IS protocol has unfolded a new stream of research regarding its Dijkstra algorithm of shortest path first (SPF) delivery. IS-IS applicability in different scenarios. In contrast to existing can also be referred to as a link state routing protocol (LSP). distance vector protocols, the IS-IS In basic terms is a link state LSPs are obviously very complex and substantially hard to protocol (LSP) supporting extremely large networks. It is also implement, manage, and analyze for this reason, the goal of known for its robustness and an easily adaptable protocol this article is to provide a guide for effective network layout powering cutting edge technologies like the Multiprotocol Label design using the IS-IS protocol. The remaining parts of this Switching (MPLS), a system used for traffic engineering. A major reason in considering wide application of the IS-IS article is organized as follows: Part II introduces the IS-IS protocol is its ability to efficiently move large chunk of data Protocol model suite with reference to previous works done, within group of connected computers or within a network(area) Part III explains features of IS-IS protocol, Part IV presents and still achieving best route for data delivery. Because of the the simulation results and findings, and Part V is the ability of the Optimized Network Engineering Tool (OPNET) to conclusion and guide for further studies. effectively study the internal operations of a simulated network, II. IS-IS Routing Protocols we conducted experiments using OPNET to demonstrate various implemented features of IS-IS and to explain their configuration. As an LSP, IS-IS offers a wide range of features. Due to the scope of this article, we will focus on the following features I. INTRODUCTION of IS-IS: When looking at routing protocols, a very critical question comes to mind: "Which protocol to use?". The full-evidence IS-IS uses a Network Entity Title (NET0 approach to use is to set up a system and utilize the belonging to the OSI network addresses. conventions that may conceivably suit the system's needs. This will end up being incredibly wasteful and costly in A minimum of one NET must make up a functional time, cash and assets. To give a response to this inquiry, IS-IS. simulation come into play. System simulation is a strategy IS-IS allows for the configuration of Two-level for demonstrating the conduct of a system by figuring the hierarchy collaboration between the distinctive system elements, Routes within an area is maintained by a Level 1 utilizing numerical equations, or changing system while routes between areas are maintained by Level composition, conventions or protocols in other to test the 2 routers. desired network. Such simulation can be performed by different software, (for example, OPNET, ns, NetSim and so A. How IS-IS operate forth.) also called network simulators. A simulation system is a software intended to evaluate the behavior of a network, IS-IS protocol is separate from other IP protocols as it arranged by assessing the execution of a model that relates operates on Open Systems Interconnection (OIS) layer 2. to the system that should be developed. For this situation, Two-level hierarchy are used to support large routing the OPNET simulation system was used to demonstrate domains. To do this, large domains are divided into areas various implemented features of IS-IS, and to describe how with each system residing on an area. Routing within a to configure and study the IS-IS model. IS-IS is a routing designated area is referred to as level 1 routing whereas protocol designed based on the DECnet phase V routing. routing between different areas is known as level 2 routing. Here routers referred to as intermediate systems exchange A level 2 system records paths (tracks) followed from one routing information via a line metric in other to learn a area to another whereas the paths within an area is recorded networks’ topology. IS-IS routing protocol is like the Open by a level 1 system. For messages (packets) destined to a Shortest Path First (OSPF). OSPF has an original different area, a level 1 system sends such packet to level 2 specification, the ISO 10589, which describes how IS-IS is system without considering the destination of the packet, the used for routing based on the ISO Connectionless Network level 2 system then handles delivery to the destination router Protocol. Later, IS-IS was enhanced to allow for routing in by forwarding the packet to the target destination. Note, this IP Networks. form of packet transfer can lead to a suboptimal routing of Revised Manuscript Received on June 7, 2019 Arif Sari, Department of Management Information systems The packet. To avoid a suboptimal routing, an SPM is applied. American University, Cyprus Joshua Chibuike Sopuru, Department of Management Information systemsThe American University, Cyprus ÖnderOnursal, Department of Management Information systems The American University, Cyprus Published By: Blue Eyes Intelligence Engineering Retrieval Number: G6290058719/19©BEIESP 2014 & Sciences Publication Is-Is Protocol Model Suite: Simulation of Implemented Features and Their Configuration. Using SPM, forwarding is based on a calculated shortest- IGRP. [3] For data transmission, dependability, internetwork path. This implies, the shortestpath is determined to ensure postponement and burden, IGRP uses a composite effectiveness of packet delivery. On a mesh topology, measurement inferred dependent on the figuring of weighted support for massive layer 2 topologies are provided by SPM qualities. The weighting component can be characterized by from a high level, IS-IS operates in the following way: managers for every measurement. Rules ought to be Neighbors are adjacencies are separated by carefully clung to before changing any esteem. transferring Hello packets from one IS router to Dependability and burden bear esteem some place in the another. scope of 1 and 255; information exchange limit can take Neighbors are established if there is a response esteems that are reflecting velocity from 1200 bps to 10 received after an initial Hello packet has been sent. Gbps, while slacks can take on any impetus from 1 to 224. A link state packet (LSP) is then built based on These wide estimation ranges are furthermore enhanced by a prefixes data and nearby connections of routers. movement of client recognizable constants. Routers within an LSP setup databases to form the The constants are hashed against the measurements in a LSP network. calculation that yields a solitary, composite measurement. The easiest and shortest way of routing paths are The system chairman can impact course choice by giving created from creating the shortest part table (SPT). higher or lower weighting to a measurement. [1] The IGRP grants a few portals to deal with their directing for certain reasons: B. Interior Routing Protocol 1. Stable steering complex frameworks. 2. No steering hovers should occur. Based on operations, behavior and need, routing protocols 3. Rapid response to changes in framework structure. can be grouped. Based on purpose, the Exterior Gateway 4. Low overhead. IGRP should not to use a bigger number Protocol (EGP) and Interior Gateway Protocol can be of information exchange limit than required for its task. grouped while the Link-state protocol, path-vector protocol 5.Dividing traffic among a couple of courses with equivalent and distance vector protocol can be grouped in respect to alluring quality. their different operations. Arranging routers in a known 6.Taking into record botch rates and measurement of traffic institution is referred to as autonomous system (AS). on different ways. Case of such basic organization incorporates an association Present utilization of IGRP oversees directing for or an organization. An ISP's system or the inward system of Transmission Control Protocol (TCP/IP). Be that as it may, an organization are instances of an AS. Based on the interior various conventions are dealt with by the ordinary structure. gateway and the exterior gateway protocol, the Internet is Only one tool is not enough to manage routing protocol. In built. IGPs are actualized for steering in AS. This idea is most cases these protocols are divided into many parts. alluded to as intra-AS directing. A few types of intra-AS Within a set of separate networks, IGPs are implemented. directing incorporate the Open Shortest Path First (OSPF), IGPs can also be implemented collectively. To establish a Routing Information Protocol (RIP), Enhanced Interior coordinated network EGPs are used. Accounts of the Gateway Routing Protocol (EIGRP) and Intermediate topology of a network are get and managed by IGPs. Due to System to Intermediate framework convention (IS-IS). the need to produce fast and reliable responds to change, Associations and specialist organizations use these IGPs are implemented A system can be misrepresented by protocols. EGPs are then again utilized for self-ruling participating system or due to an error. EGPs are applied to framework routing. This type of routing is otherwise called protect system against such misrepresentations. BGP is an between AS routing. EGP can be utilized as an example of such protocol used to achieve this.
Load more

Recommended publications
  • Solutions to Chapter 2
    CS413 Computer Networks ASN 4 Solutions Solutions to Assignment #4 3. What difference does it make to the network layer if the underlying data link layer provides a connection-oriented service versus a connectionless service? [4 marks] Solution: If the data link layer provides a connection-oriented service to the network layer, then the network layer must precede all transfer of information with a connection setup procedure (2). If the connection-oriented service includes assurances that frames of information are transferred correctly and in sequence by the data link layer, the network layer can then assume that the packets it sends to its neighbor traverse an error-free pipe. On the other hand, if the data link layer is connectionless, then each frame is sent independently through the data link, probably in unconfirmed manner (without acknowledgments or retransmissions). In this case the network layer cannot make assumptions about the sequencing or correctness of the packets it exchanges with its neighbors (2). The Ethernet local area network provides an example of connectionless transfer of data link frames. The transfer of frames using "Type 2" service in Logical Link Control (discussed in Chapter 6) provides a connection-oriented data link control example. 4. Suppose transmission channels become virtually error-free. Is the data link layer still needed? [2 marks – 1 for the answer and 1 for explanation] Solution: The data link layer is still needed(1) for framing the data and for flow control over the transmission channel. In a multiple access medium such as a LAN, the data link layer is required to coordinate access to the shared medium among the multiple users (1).
    [Show full text]
  • OSI Model and Network Protocols
    CHAPTER4 FOUR OSI Model and Network Protocols Objectives 1.1 Explain the function of common networking protocols . TCP . FTP . UDP . TCP/IP suite . DHCP . TFTP . DNS . HTTP(S) . ARP . SIP (VoIP) . RTP (VoIP) . SSH . POP3 . NTP . IMAP4 . Telnet . SMTP . SNMP2/3 . ICMP . IGMP . TLS 134 Chapter 4: OSI Model and Network Protocols 4.1 Explain the function of each layer of the OSI model . Layer 1 – physical . Layer 2 – data link . Layer 3 – network . Layer 4 – transport . Layer 5 – session . Layer 6 – presentation . Layer 7 – application What You Need To Know . Identify the seven layers of the OSI model. Identify the function of each layer of the OSI model. Identify the layer at which networking devices function. Identify the function of various networking protocols. Introduction One of the most important networking concepts to understand is the Open Systems Interconnect (OSI) reference model. This conceptual model, created by the International Organization for Standardization (ISO) in 1978 and revised in 1984, describes a network architecture that allows data to be passed between computer systems. This chapter looks at the OSI model and describes how it relates to real-world networking. It also examines how common network devices relate to the OSI model. Even though the OSI model is conceptual, an appreciation of its purpose and function can help you better understand how protocol suites and network architectures work in practical applications. The OSI Seven-Layer Model As shown in Figure 4.1, the OSI reference model is built, bottom to top, in the following order: physical, data link, network, transport, session, presentation, and application.
    [Show full text]
  • Medium Access Control Layer
    Telematics Chapter 5: Medium Access Control Sublayer User Server watching with video Beispielbildvideo clip clips Application Layer Application Layer Presentation Layer Presentation Layer Session Layer Session Layer Transport Layer Transport Layer Network Layer Network Layer Network Layer Univ.-Prof. Dr.-Ing. Jochen H. Schiller Data Link Layer Data Link Layer Data Link Layer Computer Systems and Telematics (CST) Physical Layer Physical Layer Physical Layer Institute of Computer Science Freie Universität Berlin http://cst.mi.fu-berlin.de Contents ● Design Issues ● Metropolitan Area Networks ● Network Topologies (MAN) ● The Channel Allocation Problem ● Wide Area Networks (WAN) ● Multiple Access Protocols ● Frame Relay (historical) ● Ethernet ● ATM ● IEEE 802.2 – Logical Link Control ● SDH ● Token Bus (historical) ● Network Infrastructure ● Token Ring (historical) ● Virtual LANs ● Fiber Distributed Data Interface ● Structured Cabling Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.2 Design Issues Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.3 Design Issues ● Two kinds of connections in networks ● Point-to-point connections OSI Reference Model ● Broadcast (Multi-access channel, Application Layer Random access channel) Presentation Layer ● In a network with broadcast Session Layer connections ● Who gets the channel? Transport Layer Network Layer ● Protocols used to determine who gets next access to the channel Data Link Layer ● Medium Access Control (MAC) sublayer Physical Layer Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.4 Network Types for the Local Range ● LLC layer: uniform interface and same frame format to upper layers ● MAC layer: defines medium access ..
    [Show full text]
  • The OSI Model: Understanding the Seven Layers of Computer Networks
    Expert Reference Series of White Papers The OSI Model: Understanding the Seven Layers of Computer Networks 1-800-COURSES www.globalknowledge.com The OSI Model: Understanding the Seven Layers of Computer Networks Paul Simoneau, Global Knowledge Course Director, Network+, CCNA, CTP Introduction The Open Systems Interconnection (OSI) model is a reference tool for understanding data communications between any two networked systems. It divides the communications processes into seven layers. Each layer both performs specific functions to support the layers above it and offers services to the layers below it. The three lowest layers focus on passing traffic through the network to an end system. The top four layers come into play in the end system to complete the process. This white paper will provide you with an understanding of each of the seven layers, including their functions and their relationships to each other. This will provide you with an overview of the network process, which can then act as a framework for understanding the details of computer networking. Since the discussion of networking often includes talk of “extra layers”, this paper will address these unofficial layers as well. Finally, this paper will draw comparisons between the theoretical OSI model and the functional TCP/IP model. Although TCP/IP has been used for network communications before the adoption of the OSI model, it supports the same functions and features in a differently layered arrangement. An Overview of the OSI Model Copyright ©2006 Global Knowledge Training LLC. All rights reserved. Page 2 A networking model offers a generic means to separate computer networking functions into multiple layers.
    [Show full text]
  • Security Protocols Overview an RSA Data Security Brief SSL &
    Security Protocols Overview An RSA Data Security Brief SSL & TLS Secure Socket Layer & Transport Layer Security Secure Sockets Layer (SSL) is the that do not necessarily need to be Internet security protocol for on the same secure network. point-to-point connections. It pro- Where SSL secures two applica- vides protection against eaves- tions, IPSec secures an entire net- dropping, tampering, and forgery. work. Clients and servers are able to au- thenticate each other and to estab- Applications lish a secure link, or “pipe,” across SSL can be used in any situation the Internet or Intranets to protect where a link between two comput- the information transmitted. ers or applications needs to be pro- tected. The following are just a few The Need for SSL of the real-world, practical appli- With the growth of the Internet cations of SSL & TLS: and digital data transmission, many applications need to se- curely transmit data to remote applications and computers. • Client/Server Systems SSL was designed to solve this problem in an open standard. SSL in the browser is not enough to secure most systems. Systems such as secure database access, or remote object SSL is analogous to a secure “telephone call” between two systems such as CORBA, can all be securely improved computers on any network including the Internet. In SSL, a using SSL. Other applications include redirection of se- connection is made, parties authenticated, and data securely cure connections such as proxy servers, secure Webserver exchanged. The latest enhancement of SSL is called Trans- plug-ins, and Java “Servlets.” port Layer Security (TLS).
    [Show full text]
  • Chapter 4 Network Layer
    Chapter 4 Network Layer A note on the use of these ppt slides: We’re making these slides freely available to all (faculty, students, readers). Computer They’re in PowerPoint form so you see the animations; and can add, modify, and delete slides (including this one) and slide content to suit your needs. Networking: A Top They obviously represent a lot of work on our part. In return for use, we only ask the following: Down Approach v If you use these slides (e.g., in a class) that you mention their source th (after all, we’d like people to use our book!) 6 edition v If you post any slides on a www site, that you note that they are adapted Jim Kurose, Keith Ross from (or perhaps identical to) our slides, and note our copyright of this Addison-Wesley material. March 2012 Thanks and enjoy! JFK/KWR All material copyright 1996-2012 J.F Kurose and K.W. Ross, All Rights Reserved Network Layer 4-1 Chapter 4: outline 4.1 introduction 4.5 routing algorithms 4.2 virtual circuit and § link state datagram networks § distance vector 4.3 what’s inside a router § hierarchical routing 4.4 IP: Internet Protocol 4.6 routing in the Internet § datagram format § RIP § IPv4 addressing § OSPF § BGP § ICMP § IPv6 4.7 broadcast and multicast routing Network Layer 4-2 Interplay between routing, forwarding routing algorithm determines routing algorithm end-end-path through network forwarding table determines local forwarding table local forwarding at this router dest address output link address-range 1 3 address-range 2 2 address-range 3 2 address-range 4 1 IP destination
    [Show full text]
  • CSCI-1680 Network Layer: Wrapup
    CSCI-1680 Network Layer: Wrapup Rodrigo Fonseca Based partly on lecture notes by Jennifer Rexford, Rob Sherwood, David Mazières, Phil Levis, John JannoA Administrivia • Homework 2 is due tomorrow – So we can post solutions before the midterm! • Exam on Tuesday – All content up to today – Questions similar to the homework – Book has some exercises, samples on the course web page (from previous years) Today: IP Wrap-up • IP Service models – Unicast, Broadcast, Anycast, Multicast • IPv6 – Tunnels Different IP Service Models • Broadcast: send a packet to all nodes in some subnet. “One to all” – 255.255.255.255 : all hosts within a subnet, never forwarded by a router – “All ones host part”: broadcast address • Host address | (255.255.255.255 & ~subnet mask) • E.g.: 128.148.32.143 mask 255.255.255.128 • ~mask = 0.0.0.127 => Bcast = 128.148.32.255 • Example use: DHCP • Not present in IPv6 – Use multicast to link local all nodes group Anycast • Multiple hosts may share the same IP address • “One to one of many” routing • Example uses: load balancing, nearby servers – DNS Root Servers (e.g. f.root-servers.net) – Google Public DNS (8.8.8.8) – IPv6 6-to-4 Gateway (192.88.99.1) Anycast Implementation • Anycast addresses are /32s • At the BGP level – Multiple ASs can advertise the same prefxes – Normal BGP rules choose one route • At the Router level – Router can have multiple entries for the same prefx – Can choose among many • Each packet can go to a different server – Best for services that are fne with that (connectionless, stateless) Multicast
    [Show full text]
  • Data Link Layer Design Issues • Error Detection and Correction • Elementary Data Link Protocols • Sliding Window Protocols • Example Data Link Protocols
    The Data Link Layer Chapter 3 • Data Link Layer Design Issues • Error Detection and Correction • Elementary Data Link Protocols • Sliding Window Protocols • Example Data Link Protocols Revised: August 2011 CN5E by Tanenbaum & Wetherall, © Pearson Education-Prentice Hall and D. Wetherall, 2011 The Data Link Layer Application Responsible for delivering frames of information over a single link Transport Network • Handles transmission errors and Link regulates the flow of data Physical CN5E by Tanenbaum & Wetherall, © Pearson Education-Prentice Hall and D. Wetherall, 2011 Data Link Layer Design Issues • Frames » • Possible services » • Framing methods » • Error control » • Flow control » CN5E by Tanenbaum & Wetherall, © Pearson Education-Prentice Hall and D. Wetherall, 2011 Frames Link layer accepts packets from the network layer, and encapsulates them into frames that it sends using the physical layer; reception is the opposite process Network Link Virtual data path Physical Actual data path CN5E by Tanenbaum & Wetherall, © Pearson Education-Prentice Hall and D. Wetherall, 2011 Possible Services Unacknowledged connectionless service • Frame is sent with no connection / error recovery • Ethernet is example Acknowledged connectionless service • Frame is sent with retransmissions if needed • Very unreliable channels; Example is 802.11 • NOTE: DL acknowledgement is an optimization to improve performance for unreliable channels, ACKs can also be done at higher layers Acknowledged connection-oriented service • Connection is set up; rare • Long
    [Show full text]
  • Medium Access Control Sublayer
    Telematics Chapter 5: Medium Access Control Sublayer User Server watching with video Beispielbildvideo clip clips Application Layer Application Layer Presentation Layer Presentation Layer Session Layer Session Layer Transport Layer Transport Layer Network Layer Network Layer Network Layer Prof. Dr. Mesut Güneş Data Link Layer Data Link Layer Data Link Layer Computer Systems and Telematics (CST) Physical Layer Physical Layer Physical Layer Distributed, embedded Systems Institute of Computer Science Freie Universität Berlin http://cst.mi.fu-berlin.de Contents ● Design Issues ● Metropolitan Area Networks ● Network Topologies (()MAN) ● The Channel Allocation Problem ● Wide Area Networks (WAN) ● Multiple Access Protocols ● Frame Relay ● Ethernet ● ATM ● IEEE 802.2 – Logical Link Control ● SDH ● Token Bus ● Network Infrastructure ● Token Ring ● Virtual LANs ● Fiber Distributed Data Interface ● Structured Cabling Prof. Dr. Mesut Güneş ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.2 Design Issues Prof. Dr. Mesut Güneş ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.3 Design Issues ● Two kinds of connections in networks ● Point-to-point connections OSI Reference Model ● Broadcast (Multi-access channel, Application Layer Random access channel) Presentation Layer ● In a network with broadcast Session Layer connections ● Who gets the channel? Transport Layer Network Layer ● PtProtoco ls use dtdtd to determ ine w ho gets next access to the channel Data Link Layer ● Medium Access Control (()MAC) sublay er Phy sical Laye r Prof. Dr. Mesut Güneş ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.4 Network Types for the Local Rang e ● LLC layer: uniform interface and same frame format to upper layers ● MAC layer: defines medium access - LLC IEEE 802.2 Logical Link Control ..
    [Show full text]
  • Network Layer/Internet Protocols Ip
    04 2080 CH03 8/16/01 1:34 PM Page 61 CHAPTER 3 NETWORK LAYER/INTERNET PROTOCOLS You will learn about the following in this chapter: • IP operation, fields and functions • ICMP messages and meanings • Fragmentation and reassembly of datagrams IP IP (Internet Protocol) does most of the work in the TCP/IP protocol suite. All protocols and applications within the TCP/IP suite run on top of IP and utilize it for logical Network layer addressing and transmission of datagrams between internet hosts. IP maps to the Internet layer of the DoD and to the Network layer of the OSI models. ICMP (Internet Control Message Protocol) is considered an integral part of IP and uses IP for its datagram delivery; we will dis- cuss ICMP later in this chapter. Figure 3.1 shows how IP maps to the DoD and OSI models. How Do I Buy a Ticket on the IP Train? The phrase ”runs on top of” might sound as if an application or protocol is buying a ticket to ride on an IP train. This term is not restricted to IP. In reality, it is industry jargon used to describe any upper- layer protocol or application coming down the OSI model and utilizes another lower-layer protocol’s features (in this case IP at the Network layer). IP provides an unreliable, connectionless datagram delivery service, which means that IP does not guarantee that an IP datagram successfully reaches its destination; rather it provides best effort of delivery, which means it sends it out and hopes it gets there.
    [Show full text]
  • The Network Layer
    TheThe NetworkNetwork LayerLayer • Concerned with getting packets from the source all the way to the destination: Routing through the subnet, load balancing, congestion control. • Protocol Data Unit (PDU) for network layer protocols = packet • Types of network services to the transport layer: – Connectionless: Each packet carries full destination address. – Connection-oriented: • Connection is set up between network layer processes on the sending and receiving sides. • The connection is given a special identifier until all data has been sent. • Internal organization of the network layer (in the subnet): – Datagram: Packets are sent and routed independently with each carrying the full destination address (TCP/IP) – Virtual circuit: A virtual circuit is set up to the destination using a circuit number stored in tables in routers along the way. Packets only carry the virtual circuit number. All packets follow the same route (ATM). EECC694 - Shaaban #1 Final Review Spring2000 5-11-2000 RoutingRouting AlgorithmsAlgorithms To decide which output line an incoming packet should be transmitted on. • Static Routing (Nonadaptive algorithms): – Shortest path routing: • Build a graph of the subnet with each node representing a router and each arc representing a communication link. • The weight on the arcs represents: a function of distance, bandwidth, communication costs mean queue length and other performance factors. • Several algorithms exist including Dijkstra’s shortest path algorithm. – Selective flooding: Send the packet on all output lines going in the right direction to the destination. – Flow-based routing: Based on known capacity and link loads. EECC694 - Shaaban #2 Final Review Spring2000 5-11-2000 StaticStatic Routing:Routing: ShortestShortest PathPath RoutingRouting • First five steps of an example using Dijktra’s algorithm EECC694 - Shaaban #3 Final Review Spring2000 5-11-2000 StaticStatic Routing:Routing: Flow-BasedFlow-Based RoutingRouting • A routing matrix is constructed; used when the mean data flow in network links is known and stable.
    [Show full text]
  • TESLA: a Transparent, Extensible Session-Layer Architecture for End-To-End Network Services
    TESLA: A Transparent, Extensible Session-Layer Architecture for End-to-end Network Services Jon Salz Alex C. Snoeren MIT Laboratory for Computer Science University of California, San Diego [email protected] [email protected] Hari Balakrishnan MIT Laboratory for Computer Science [email protected] Session-layer services for enhancing functionality and ² Encryption services for sealing or signing ¤ows. improving network performance are gaining in impor- ² General-purpose compression over low-bandwidth tance in the Internet. Examples of such services in- links. clude connection multiplexing, congestion state shar- ² ing, application-level routing, mobility/migration sup- Traf£c shaping and policing functions. port, and encryption. This paper describes TESLA, a These examples illustrate the increasing importance of transparent and extensible framework allowing session- session-layer services in the Internet—services that oper- layer services to be developed using a high-level ¤ow- ate on groups of ¤ows between a source and destination, based abstraction. TESLA services can be deployed and produce resulting groups of ¤ows using shared code transparently using dynamic library interposition and and sometimes shared state. can be composed by chaining event handlers in a graph structure. We show how TESLA can be used to imple- Authors of new services such as these often imple- ment several session-layer services including encryption, ment enhanced functionality by augmenting the link, net- SOCKS, application-controlled routing, ¤ow migration, work, and transport layers, all of which are typically im- and traf£c rate shaping, all with acceptably low perfor- plemented in the kernel or in a shared, trusted interme- mance degradation.
    [Show full text]