routing table ,What is routing ? , what is static routing , what is dynamic routing , types of routing , routing protocols , routing strategy , Download Routing pdf , Download routing ppt , download routing notes , paper on routing
To Download Complete Documentation Visit My Blog
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Data Communications,Data Networks,computer communications,multiplexing,spread spectrum,protocol architecture,data link protocols,signal encoding techniques,transmission media,asynchronous transfer mode,routing
Routing is the process of selecting a path for traffic in a network or between or across multiple networks. this slide helps to describe routing protocols and their various aspects.
routing table ,What is routing ? , what is static routing , what is dynamic routing , types of routing , routing protocols , routing strategy , Download Routing pdf , Download routing ppt , download routing notes , paper on routing
To Download Complete Documentation Visit My Blog
http://studyofcs.blogspot.com/2015/06/what-is-routerwhat-is-routing.html
Download completer BS Computer Science Degree Study Data
http://studyofcs.blogspot.com/p/bs.html
Data Communications,Data Networks,computer communications,multiplexing,spread spectrum,protocol architecture,data link protocols,signal encoding techniques,transmission media,asynchronous transfer mode,routing
Routing is the process of selecting a path for traffic in a network or between or across multiple networks. this slide helps to describe routing protocols and their various aspects.
this is a presentation i made to give some introduction to the backward learning algorithm hope it would be use full.Many places were referred to get information here
Routing is the operation of transferring information transversely through an internetwork from a source to a destination. Alongside the approach, as a minimum one middle node normally is found. Routing is frequently compared with bridging, Copy the link given below and paste it in new browser window to get more information on Network Routing:- http://www.transtutors.com/homework-help/computer-science/network-routing.aspx
The network layer is responsible for routing packets from the source to destination. The routing algorithm is the piece of software that decides where a packet goes next (e.g., which output line, or which node on a broadcast channel).For connectionless networks, the routing decision is made for each datagram. For connection-oriented networks, the decision is made once, at circuit setup time.
Routing Issues
The routing algorithm must deal with the following issues:
Correctness and simplicity: networks are never taken down; individual parts (e.g., links, routers) may fail, but the whole network should not.
Stability: if a link or router fails, how much time elapses before the remaining routers recognize the topology change? (Some never do..)
Fairness and optimality: an inherently intractable problem. Definition of optimality usually doesn't consider fairness. Do we want to maximize channel usage? Minimize average delay?
When we look at routing in detail, we'll consider both adaptive--those that take current traffic and topology into consideration--and nonadaptive algorithms.
Various routing algorithm are used for the purpose of deciding which route an incoming data packet needs to be transmitted on to reach destination efficiently.
These are the algorithms which change their routing decisions whenever network topology or traffic load changes
The Bellman–Ford algorithm is an algorithm that computes shortest paths from a single source vertex to all of the other vertices in a weighted digraph.
this is a presentation i made to give some introduction to the backward learning algorithm hope it would be use full.Many places were referred to get information here
Routing is the operation of transferring information transversely through an internetwork from a source to a destination. Alongside the approach, as a minimum one middle node normally is found. Routing is frequently compared with bridging, Copy the link given below and paste it in new browser window to get more information on Network Routing:- http://www.transtutors.com/homework-help/computer-science/network-routing.aspx
The network layer is responsible for routing packets from the source to destination. The routing algorithm is the piece of software that decides where a packet goes next (e.g., which output line, or which node on a broadcast channel).For connectionless networks, the routing decision is made for each datagram. For connection-oriented networks, the decision is made once, at circuit setup time.
Routing Issues
The routing algorithm must deal with the following issues:
Correctness and simplicity: networks are never taken down; individual parts (e.g., links, routers) may fail, but the whole network should not.
Stability: if a link or router fails, how much time elapses before the remaining routers recognize the topology change? (Some never do..)
Fairness and optimality: an inherently intractable problem. Definition of optimality usually doesn't consider fairness. Do we want to maximize channel usage? Minimize average delay?
When we look at routing in detail, we'll consider both adaptive--those that take current traffic and topology into consideration--and nonadaptive algorithms.
Various routing algorithm are used for the purpose of deciding which route an incoming data packet needs to be transmitted on to reach destination efficiently.
These are the algorithms which change their routing decisions whenever network topology or traffic load changes
The Bellman–Ford algorithm is an algorithm that computes shortest paths from a single source vertex to all of the other vertices in a weighted digraph.
Network Lifetime Analysis of Routing Protocols of Short Network in QualnetIOSR Journals
Abstract: A Mobile Ad-Hoc Network (MANET) is a collection of wireless mobile nodes that communicates with each other without using any existing infrastructure, access point or centralized administration. Mobile ad-hoc network have the attributes such as wireless connection, continuously changing topology, distributed operation and ease of deployment. In this paper we have compared the energy consumption of reactive, proactive & hybrid routing protocol AODV,DSR,RIP & ZRP by using different mobility model. We have analyzed the Network lifetime of protocols by varying pay load, mobility, pause time and type of traffic (CBR). A detailed simulation has been carried out in qualnet. The metrics used for performance analysis are energy consumed & battery consumption. It has been observed that RIP has better network lifetime than other.
A PROJECT REPORT
On
CISCO CERTIFIED NETWORK ASSOCIATE
A computer network, or simply a network, is a collection of computer and other hardware components interconnected by communication channels that allow sharing of resources and information. Where at least one process in one device is able to send/receive data to/from at least one process residing in a remote device, then the two devices are said to be in a network. Simply, more than one computer interconnected through a communication medium for information interchange is called a computer network.
In distance vector routing, the least-cost route between any two nodes is the route with minimum distance.
In this protocol, as the name implies, each node maintains a vector (table) of minimum distances to every node.
The table at each node also guides the packets to the desired node by showing the next stop in the route (next-hop routing).
Each node knows how to reach any other node and the cost. At the beginning, however, this is not the case the distance between itself and its immediate neighbors, those directly connected to it.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
"Impact of front-end architecture on development cost", Viktor TurskyiFwdays
I have heard many times that architecture is not important for the front-end. Also, many times I have seen how developers implement features on the front-end just following the standard rules for a framework and think that this is enough to successfully launch the project, and then the project fails. How to prevent this and what approach to choose? I have launched dozens of complex projects and during the talk we will analyze which approaches have worked for me and which have not.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
To view the webinar recording, go to:
https://www.rttsweb.com/jmeter-integration-webinar
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
2. Introduction
• Routers forward IP datagrams from one router
to another on the path from source towards
destination
• Routing protocols
—To decide on routes to be taken
• Routers must have idea of topology of internet
in order to pick best route to take
—Decisions based on some least cost criteria
—May depend on the current conditions
3. A Sample Configuration of
Routers and Networks
• Link costs are
at the output of
the links
• There is no
cost of getting
data from the
network
• For example,
the cost of the
path X-A-F-Y
is 1+1+4=6
4. Routing Table
• One routing table is needed for each router
• One entry for each destination network
—Not for each destination host
—Once datagram reaches router attached to destination network,
that router can deliver to host
• Each entry shows next node on the route to destination
—Not whole route
• Routing tables may also exist in hosts
—If multiple routers attached to network, host needs table saying
which to use
—If the attached network has single router, then not needed
• All traffic must go through that router (called the gateway)
6. Fixed Routing
• Single permanent route configured for each
source-destination pair
—Routes are fixed
—May change when topology changes (not so often)
• No dynamic updates
7. Adaptive Routing
• As conditions on internetwork change, routes
may change
—Failure
• of routers or networks
—Congestion
• If a particular section of the network is heavily congested, it
is better not to use that part and change the route
8. Adaptive Routing - Challenges
• Complex routing decisions
—Router processing increases
• Depends on information collected in one place
but used in another
—More information exchanged improves routing
decisions but increases overhead
• May react too fast
—causing congestion through oscillation (fluttering)
• May react too slow
—By the time routing decision changes, the network
conditions may be much more different
9. Adaptive Routing - Challenges
• Looping
—Packet forwarded by a router eventually returns to
that router
—May occur when changes in connectivity not
propagated fast enough to all other routers
—An important pathology that must be prevented in
routing algorithms
• Despite all challenges, adaptive routing prevails
due to its flexibility
10. Classification of Adaptive
Routing Strategies
• Based on information sources
—Local
• E.g. route each datagram to network with shortest queue
– Balance loads on outgoing networks
– May not be heading in correct direction
• Rarely used
—Adjacent nodes
• Delay and outage info from adjacent nodes
• Distance vector algorithms
– Discussed later
—All nodes
• Link-state algorithms
– Discussed later
11. Flooding
• No network info required
• Packet sent by node to every neighbor
• Incoming packets retransmitted on every link
except incoming link
• Eventually a number of copies will arrive at
destination
• Each packet is uniquely numbered so duplicates
can be discarded at destination
13. Flooding
• Precautions against unlimited grow in circulation
—Nodes can remember packets already forwarded to
keep network load in bounds
• called "Restricted Flooding"
—Include a hop count in packets.
• Set to a maximum value
• Decrease one at each hop
• Discard when 0
14. Properties of Flooding
• All possible routes are tried
—very robust
—can be used for emergency messaging
• At least one packet will use minimum hop count
route
—Can be used once to set up a route
• All nodes are visited
—Useful to distribute information (e.g. routing info)
15. Random Routing
• Node selects one outgoing path for
retransmission of incoming packet
• Selection is at random
—equally likely
• all outgoing links are utilized equally in the long-run
—can select outgoing path based on a probability
• e.g. probability based on data rate
– good traffic distribution
• No network info needed
• Route is typically neither least cost nor minimum
hop
16. Autonomous Systems (AS)
• An important concept for TCP/IP routing in IP
layer
• AS is defined as set of routers and networks
managed by single organization (e.g. an ISP)
—Exchange routing information in itself
—Common routing protocol
• An AS must be connected in itself
—There is at least one route between any pair of nodes
17. Interior Routing Protocol (IRP)
Exterior Routing Protocol (ERP)
• (not actually protocols, just concepts)
• IRP passes routing information between routers
within AS
—Need exchange of info among the routers only in AS
—Different autonomous systems may have different
IRP mechanisms
• Autonomous systems need to talk to each other
—Need minimum information from other connected AS
—A few routers in each AS must talk
—Use Exterior Routing Protocol (ERP)
• Again, a concept
—ERP does not deal with details within source and
target AS
19. Approaches to Routing –
Distance-vector
• Each router exchange information with neighboring routers
—Definition: Two nodes are said to be neighbors if both are directly
connected to the same network
• Each node keeps
—distance vector and next-hop vector (Routing table)
• One entry for each destination network
—a vector of link costs for each directly attached network
• First generation routing algorithm for ARPANET
• Used by Routing Information Protocol (RIP)
—will discuss later
• Requires transmission of information by each router to all
neighbors
—Distance vector that contain estimated path costs for all destination
networks
—Changes may take long time to propagate
20. Approaches to Routing –
Link-state
• Designed to overcome drawbacks of distance-vector
• When router initialized, it determines link cost on each interface
• Advertises set of link costs to all other routers in topology
— Not just neighboring routers
• After that, each router monitors its link costs
— If significant change, router advertises new set of link costs
• In this way, each router builds up a picture of the entire topology
— Can calculate shortest path to each destination
— Use an algorithm to determine shortest paths
• In practice, Dijkstra's algorithm
• Router constructs routing table, listing first hop to each destination
• Second generation routing algorithm for ARPANET
• Open shortest path first (OSPF) protocol uses link-state routing.
21. Distance-vector and Link State
• Both of them is suitable for IRP, not ERP
• Several reasons. Some of them:
—Both require homogenous metrics that may be the
case within an AS, but we cannot assume then same
for several AS systems
—Flooding the link state information across multiple AS
systems is not scalable
22. Approaches to Routing –
Path-vector
• Suitable approach for Exterior Router Protocols
• Provide information about which networks can
be reached by a given router and Autonomous
Systems crossed to get there
—Does not include distance or cost estimate
• BGP (Border Gateway Protocol) is an example
to path-vector routing protocol
23. Least Cost Algorithms
• Routing decision is based on some least-cost criteria
(minimization problem)
—If minimize number of hops, link cost is 1
—Link cost may be inversely proportional to capacity, proportional
to current load (queue length), or some combination
—May be different in two directions (e.g. if cost is queue length)
• More formal problem definition
—For each pair of nodes,
find the least cost path
—Cost of path between two nodes
is sum of costs of links traversed
• Dijkstra's algorithm
• Bellman-Ford algorithm
24. Dijkstra's Algorithm
• Find shortest paths from a given node to all
other nodes, by developing paths in the order of
increasing path length (cost)
• Proceeds in stages
—At each stage shortest path from source to one node
is determined
—The nodes for which shortest path determined are
kept in a set called T
—At each iteration, node not in T but has the shortest
path from source added to T
—As each node added to T, path from source to the
nodes not in T are checked to see whether there is a
better path through this newly added node
25. Dijkstra's Algorithm –
Formal (1)
• N = set of nodes in the network
• s = source node
• T = set of nodes so far incorporated (shortest path
found)
• w(i, j) = link cost from node i to node j
w(i, i) = 0
w(i, j) = ∞ if nodes not directly connected
w(i, j) ≥ 0 if nodes are directly connected
• L(n) = cost of current least-cost path from s to n
—At the end of algorithm (actually as soon as n is added to T),
L(n) is the cost of least-cost path from s to n
26. [Initialization]
T = {s}
i.e. set of nodes so far incorporated consists of only source node
L(n) = w(s, n) for all n ≠ s
i.e. initial path costs to neighboring nodes are link costs
Dijkstra's Algorithm –
Formal (2)
27. Repeat
[Get Next Node]
Find neighboring node not in T with least-cost path from s
Find x ∉ T such that
Add x to T. L(x) is the shortest path from s to x.
[Update Least-Cost Paths]
L(n) = min[L(n), L(x) + w(x, n)] for all n ∉ T
If the latter term is the minimum, the path from s to n is now
the path from s to x concatenated with the edge from x to n.
Until all nodes are in T
Dijkstra's Algorithm –
Formal (3)
Lx( )=
min
j∉T
L j()
29. Bellman-Ford Algorithm
• Iterative
1.find the shortest paths from a source to all possible
destinations using only one link
2.then using max. two links by adding appropriate links
to the paths of step 1
3.then using max. 3 links on top of paths with two links
4.so on .. until no improvement is gained by adding
more links
30. Bellman-Ford Algorithm –
Formal (1)
• s = source node
• w(i, j) = link cost from node i to node j
w(i, i) = 0
w(i, j) = ∞ if nodes are directly connected
w(i, j) ≥ 0 if nodes directly connected
• h = maximum number of links in path at
current stage
• Lh(n) =cost of least-cost path from s to n such
that path contains no more than h links
32. Bellman-Ford Algorithm –
Formal (3)
[Update]
Loop until no more improvements
For each n ≠ s, compute
If s-to-n cost reduced, then path also
changes to s -…- j - n
h=h+1
Lh+1 n( )=
min
j
Lh j( )+ w j, n( )[ ]
34. RIP (Routing Information
Protocol)
• Uses Distance Vector Routing approach
—Each node exchanges information with neighbors
—Directly connected by same network
• Each node maintains three vectors
—Link cost
• One entry for each network it attaches
—Distance vector (metric column in the next slide)
• Current cost of route from the node to each destination network in the
configuration
—Next hop vector (Next router column in the next slide)
• The next router for each destination network in the configuration
• Every 30 seconds, exchange distance vector with neighbors
• Use distance vectors received from neighbors to update
distance and next hop vector
—Similar to Bellman-Ford algorithm.
Routingtable
36. RIP Details –
Incremental Update
• Previous algorithm implies that all distance
vector updates arrive within a small window of
time
—Not correct, because (i) no synchronization, (ii) RIP
uses UDP that means no reliability.
• Actually RIP is designed to operate
incrementally. Tables are updated after receipt
of individual distance vector
37. RIP Details –
Topology Change
• If no updates are received from a router within
180 seconds, mark the connection as invalid
—Assumes router crash or network connection
unstable
—Set distance value to infinity
• Actually 16. Why? See next.
38. Counting to Infinity Problem (1)
• A problem of RIP is slow convergence to a change in topology
• Consider the example network below with all link costs 1
— The distance of B to network 5 is 2, next hop is D
— A and C have distances of 3 and next hop is B
39. Counting to Infinity Problem (2)
• Suppose router D fails:
—B determines network 5 no longer reachable via D
• Sets distance to 4 based on report from A or C
—At next update, B tells A and C this new distance to network 5
—A and C receive this and increment their network 5 distance to 5
• 4 from B, plus 1 to reach B
—B receives distance count 5 and assumes network 5 is 6 unit
cost away
—Repeat until reach infinity (16)
—Update interval is 30 seconds, so reaching 16 takes several
minutes. If infinity is larger, then convergence would take longer.
40. Split Horizon Rule
• Counting to infinity problem is caused by
misunderstanding between B and A, and
between B and C
—Each thinks it can reach network 5 via the other
• Split Horizon rule says “do not send information
about a route back in the direction it came from”
—Router sending information is nearer to the destination
than you are
—Don't teach your grandma how to suck eggs!
• Erroneous route now eliminated within time out
period (180 seconds)
41. Read from book (page 404 –
405)
• RIP Packet Format
• RIP limitations
42. Open Shortest Path First
(OSPF)
• RIP is limited in large internets
• OSPF is preferred interior routing protocol for
TCP/IP based internets
• Link state routing used
43. Link State Routing
• When initialized, router determines link cost on
each interface
• Router advertises these costs to all other
routers in topology
• Router monitors its costs
—When changes occur, costs are re-advertised
• Each router constructs topology and calculates
shortest path to each destination network
—Can use any algorithm, but in practice Dijkstra is
used
44. OSPF Overview
• Router maintains the state of local links
• Transmits updated state information to all
routers in AS or in area (see later)
• Router receiving update must acknowledge
• Each router maintains a database that reflects
the topology
—Directed graph
—And then generates a spanning tree and routing table
45. Router Database Graph
• Vertices (nodes)
—Routers
—Networks
• Edges
—Connecting two routers
—Connecting router to network
47. Directed Graph of Sample
Autonomous System
Each router
applies
Dijkstra
algorithm on
this graph to
find out
minimum
path to each
destination
network
49. Link Costs
• Cost of each hop in each direction is called routing metric
• OSPF provides flexible metric scheme based on type of
service
—Normal
• Default metric assigned by administrators
• Typically 1 for minimum hop routing
—Monetary cost
—Reliability
• E.g. based on recent history of outages
—Throughput
• Inversely proportional to data rate
—Delay
• Based on propagation and queueing delays for each interface of the
routers
• Each router generates 5 spanning trees and 5 routing tables
50. Areas
• Make large autonomous systems more
manageable
• Configured as a backbone and multiple areas
• Area – Collection of contiguous networks and
hosts plus routers connected them
—Not so different from AS, but smaller
• Backbone – networks and routers that connect
multiple areas as a central hub
—Like a star topology
51. Operation of Areas
• Each area runs a separate copy of the link state
algorithm
—Topological database and graph of just that area
—Link state information broadcast to other routers in
area
—Reduces traffic
—Intra-area routing relies solely on local link state
information
52. Inter-Area Routing
• Path consists of three legs
—Within source area
• Intra-area
• Delivers to the backbone
—Through backbone
• Has properties of an area
• Uses link state routing algorithm
• Delivers to the destination area
—Within destination area
• Intra-area
• Delivers to recipient
54. Border Gateway Protocol (BGP)
• For use with TCP/IP internets
• Preferred ERP of the Internet
• Allows routers (gateways) in different
Autonomous Systems to exchange routing
information
• Current version is BGP-4
—RFC 4271
• No time to cover
—See the book for details (in Chapter 12)
—Not responsible