This presentation contains Networking Basics Concepts and basic topologies of Computer Networking discussed. Also gives information about Cisco History.
This presentation contains Networking Basics Concepts and basic topologies of Computer Networking discussed. Also gives information about Cisco History.
Slide deck from our Basics of Computer Networking webinar lead by instructor Daniel Cummins. Networks are as different as the people and organizations that use them. Despite those differences, there are some foundational components that all networks share. Explore different types of networks and the common components that must exist in these networks. Learn more about TCP/IP, the protocol suite that connects the whole world together and look at the ways in which we connect to the world via the Internet. Topics covered include network components, network types, and network protocols. For more information on networking training, visit https://ter.li/37zcnu
Wireless networks come in many different forms, cover various distances, and provide a range of low to
high bandwidth depending on the type installed. Wireless LAN – Wireless LAN enable Laptop users to
access the Network of a company.
The Slides include a brief description of what is a Wireless LAN, some benefits over a wired network connection, where is WLAN mainly applied, how is the infrastructure of a Wireless LAN, the architecture of an ad-hoc Network, the range & throughput of the wireless ethernet and how to secure the wireless LAN.
"This presentation was created through wide-ranged research and is intended specially for everyone interested in network technology".
-BRIAN S. CUNAL
KALINGA-APAYAO STATE COLLEGE
IT Instructor.
(Emerald Communication is a leading provider of telecom network transport, connectivity, TV transmission services, and data services to the wholesale communications & Internet communities. Emerald Communication provides consultancy services by having the skills and a wealth of experience to understand and to develop people and organizations.)
A network consists of a collection of computers, printers and other compatible equipment/ hardware
that is connected together so that they can communicate with each other.
Slide deck from our Basics of Computer Networking webinar lead by instructor Daniel Cummins. Networks are as different as the people and organizations that use them. Despite those differences, there are some foundational components that all networks share. Explore different types of networks and the common components that must exist in these networks. Learn more about TCP/IP, the protocol suite that connects the whole world together and look at the ways in which we connect to the world via the Internet. Topics covered include network components, network types, and network protocols. For more information on networking training, visit https://ter.li/37zcnu
Wireless networks come in many different forms, cover various distances, and provide a range of low to
high bandwidth depending on the type installed. Wireless LAN – Wireless LAN enable Laptop users to
access the Network of a company.
The Slides include a brief description of what is a Wireless LAN, some benefits over a wired network connection, where is WLAN mainly applied, how is the infrastructure of a Wireless LAN, the architecture of an ad-hoc Network, the range & throughput of the wireless ethernet and how to secure the wireless LAN.
"This presentation was created through wide-ranged research and is intended specially for everyone interested in network technology".
-BRIAN S. CUNAL
KALINGA-APAYAO STATE COLLEGE
IT Instructor.
(Emerald Communication is a leading provider of telecom network transport, connectivity, TV transmission services, and data services to the wholesale communications & Internet communities. Emerald Communication provides consultancy services by having the skills and a wealth of experience to understand and to develop people and organizations.)
A network consists of a collection of computers, printers and other compatible equipment/ hardware
that is connected together so that they can communicate with each other.
Теоремата на фон Нойман за отсъствие на скрити параметри в квантовата механикаVasil Penchev
Mathematical formalism and reality – How Hilbert space combined Schrödinger‘s ondulatory mechanics with Heisenberg‘s matrix mechanics – Wave-corpuscular dualism from a logical viewpoint – On the relations in Russell – Schrödinger‘s paper on the equivalence of the two formulations – The conditions for such eqivalence – Matter as a „funcion of its boudaries“ – Quantum correlations and insoluble statements – Relationships „by themselves“ and relational ontology – Again about „the element of reality“ – Plato‘s Cave in the computers age – Dual vector spaces – Hypermaximal operators and physical quantities – Schrödinger‘s equation – „Yang and Yin” – The Lagrange and Hamilton formalism of mechanics – The approch of Gibbs – The principle of conservation of extension-in-phase – „Hidden parameters” and „possible worlds” – A real object being in a possible state of another – Dirac‘s δ-function – Schwartz distributions – Inseparable and rigged Hilberts spaces – What about Lorentz invariance? – Wave-corpuscular dualism – The being of a quantum entity as a question – The answer, or again about the choice – Shannon information – The „curling” of actuality by chance – Simultaneity and „eventuality” – The relativity of discreteness and continuality – „Bra and ket vectors” and their space – The Riesz representation theorem – Weak and strong topology – The impossibility of „absolutely immovable body ” – Superquantum correlations? – The Wightman axioms of quantum field – The approaces of Gibbs and Einstein for statistical description – The outlined context and the meaning of von Neumann‘s theorem – Cauasality in von Neumann – A „taoist” ilustration of it – On „hidden parameters” – Russell‘s „non-symmetrical relations” – One or more time series – The axiom of choice and the repeated choice – If we postulate correlations, and deduce indetermimism … – „No-signaling principle” and „non-signaling theories” – Simultaneity in quantum mechanics and in relativity – „Simultaneous immeasurablity ” and„simultaneous undecidablity” – The premisses of the theorem – Tsallis information – The exact statement of the theorem and its meaning – Hermitian, maximal, and hypermaximal operators – A Skolemian interpretation of the argument EPR – Again about „dualistic Pythagoreanism” – Isometric and unitary operators – Time as a „hidden parameter” – Conservation and identity
Формализъм и реалност – Как хилбертовото пространство съчета матричната механика на Хайзенберг и вълновата механика на Шрьодингер – Вълново-корпускулярният дуализъм от логическа гледна точка – За отношенията по Ръсел – Статията на Шрьодингер за еквивалентността на двете формулировки – Условията за такава еквивалентност – Материята като „функция от нейните граници” – Квантови корелации и неразрешими твърдения – Отношения „сами по себе си” и релационна онтология – Отново за „елемента на реалността” – Платоновата „пещера” в компютърната ера – Дуалните векторни пространства – Хипермаксималните оператори и физическите величини – Уравнението на Шрьодингер – „Ян и Ин” – Лагранжовият и Хамилтоновият формализъм на механиката – Подходът на Гибс –
Целта на презентацията е да разгледа най-популярните платки с ARM процесори от типа на OLinuXino, CubieBoard, Banana Pi, Beaglebone black, Odroid, Raspberry Pi и да предостави насоки как да се адаптират Linux ядрото и различни Linux дистрибуции за тях. Ще бъдат представени практически примери за работа с Das U-Boot, Linux-sunxi, Debian и Linux базираната софтуерна платформа Tizen на серията open-source hardware платки OLinuXino. Също така ще бъде споделена информация за DIY (Do It Yourself) създаване на свободни устройства с отворен хардуер и софтуер.
Представянето на новата ни Cloud платформа на Webit 2011:
- Какво е Cloud или „Облак“ и как може да ви помогне;
- Какво е нашето виждане за развитието на тези технологии;
- Демонстрация на новата ни "Облачна" платформа, базирана на OnApp;
The IP network is a virtual network and must rely on a link layer ne.pdfSALES97
The IP network is a virtual network and must rely on a link layer network to transport a frame.
What elements support getting an IP frame over an Ethernet LAN?
Solution
The data link layer (L2) is the second layer of the seven-layer OSI model of computer
networking. This layer is the protocol layer that transfers data between adjacent network nodes in
a wide area network (WAN) or between nodes on the same local area network (LAN) segment.
The data link layer, also sometimes termed as the link layer, is where many wired and wireless
local area networking (LAN) technologies primarily function.
Ethernet is the most widely used local area network (LAN) in metropolitan area networks
(MAN). Ethernet is a link layer protocol in the TCP/IP stack. It describes how networked devices
can format data for transmission to other network devices on the same network segment, and
how to put that data out on the network connection. It was commercially introduced in 1980 and
first standardized in 1983 as IEEE 802.3, and has since been refined to support higher bit rates
and longer link distances.
The data link layer is divided into two sublayers: logical link control (LLC) and media access
control (MAC).By separating LLC and MAC functions, interoperability of different network
technologies is made easier.
Data Link Layer Functions: Given below are the key tasks performed at the data link layer:
Logical Link Control (LLC): Logical link control refers to the functions required for the
establishment and control of logical links between local devices on a network. It provides
services to the network layer above it and hides the rest of the details of the data link layer to
allow different technologies to work seamlessly with the higher layers. Most local area
networking technologies use the IEEE 802.2 LLC protocol.
Media Access Control (MAC): This refers to the procedures used by devices to control access to
the network medium. Since many networks use a shared medium, it is necessary to have rules for
managing the medium to avoid conflicts. Ethernet uses the CSMA/CD method of media access
control, while Token Ring uses token passing.
Data Framing: The data link layer is responsible for the final encapsulation of higher-level
messages into frames that are sent over the network at the physical layer.
Addressing: The data link layer is the lowest layer in the OSI model that is concerned with
addressing: labeling information with a particular destination location. Each device on a network
has a unique hardware address or MAC address imbined with the hardware i.e present in network
interface card (NIC) to uniquely identify the device.
Error Detection and Handling: The data link layer handles errors that occur at the lower levels of
the network stack. For example, a cyclic redundancy check (CRC) field is often employed to
allow the station receiving data to detect if it was received correctly.
The hardware address is used for the MAC sublayer addressing. Ethernet uses the.
Ensure that only reliable networks are set up in your systems by listening to our short Webinar teaching you all about the basics of industrial ethernet communications and computer networking. Starting from the ground up, this presentation covers the basics of how network connections work, and how one computer talks to another.
РАБОТА С ОБЕКТА „ЗАЯВКА“
1. Релационни операции.
2. Характеристикина езика SQL.
3. Основни заявки на SQL.
4. Формулиране на заявки в MS Access. Практическо занятие.
РАБОТА С ОБЕКТА „ТАБЛИЦА“
1. Първичен ключ
2. Свързване на таблици в базата.Практическо занятие №1.
3. Проектиране на базата.
4. Процесът „нормализация“ на базата.
5. Анализ и нормализация на данните в СУБД Access.Практическо занятие №2.
6. Самостоятелна работа.
Предимства при използване на бази от данни
1. Основни понятия
2. Подходи за управление на данните
3. Защо да използваме база от данни
4. Основни характеристики на СУБД Access
5. Практическо занятие №1: създаване на база от данни
6. Практическо занятие №2: създаване на таблица
7. Самостоятелна работа
Essentials of Automations: The Art of Triggers and Actions in FMESafe Software
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We’ll kick things off by showcasing the most commonly used event-based triggers, introducing you to various automation workflows like manual triggers, schedules, directory watchers, and more. Plus, see how these elements play out in real scenarios.
Whether you’re tweaking your current setup or building from the ground up, this session will arm you with the tools and insights needed to transform your FME usage into a powerhouse of productivity. Join us to discover effective strategies that simplify complex processes, enhancing your productivity and transforming your data management practices with FME. Let’s turn complexity into clarity and make your workspaces work wonders!
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/
UiPath Test Automation using UiPath Test Suite series, part 5DianaGray10
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Topics covered:
CI/CD with in UiPath
End-to-end overview of CI/CD pipeline with Azure devops
Speaker:
Lyndsey Byblow, Test Suite Sales Engineer @ UiPath, Inc.
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.
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GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
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My slides at Nordic Testing Days 6.6.2024
Climate impact / sustainability of software testing discussed on the talk. ICT and testing must carry their part of global responsibility to help with the climat warming. We can minimize the carbon footprint but we can also have a carbon handprint, a positive impact on the climate. Quality characteristics can be added with sustainability, and then measured continuously. Test environments can be used less, and in smaller scale and on demand. Test techniques can be used in optimizing or minimizing number of tests. Test automation can be used to speed up testing.
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A tale of scale & speed: How the US Navy is enabling software delivery from l...sonjaschweigert1
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- Maintenance of superior security standards and inherent policy enforcement with Authorization to Operate (ATO)
Development teams can ship efficiently and ensure applications are cyber ready for Navy Authorizing Officials (AOs). In this webinar, Sigma Defense and Anchore will give attendees a look behind the scenes and demo secure pipeline automation and security artifacts that speed up application ATO and time to production.
We will cover:
- How to remove silos in DevSecOps
- How to build efficient development pipeline roles and component templates
- How to deliver security artifacts that matter for ATO’s (SBOMs, vulnerability reports, and policy evidence)
- How to streamline operations with automated policy checks on container images
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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.
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During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
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- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
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In his public lecture, Christian Timmerer provides insights into the fascinating history of video streaming, starting from its humble beginnings before YouTube to the groundbreaking technologies that now dominate platforms like Netflix and ORF ON. Timmerer also presents provocative contributions of his own that have significantly influenced the industry. He concludes by looking at future challenges and invites the audience to join in a discussion.
2. Chapter 5 : Objectives
In this chapter, you will learn to:
Describe the operation of the Ethernet sublayers.
Identify the major fields of the Ethernet frame.
Describe the purpose and characteristics of the Ethernet
MAC address.
Describe the purpose of ARP.
Explain how ARP requests impact network and host
performance.
Explain basic switching concepts.
Compare fixed configuration and modular switches.
Configure a Layer 3 switch.
3. Ethernet
Introduction
This chapter examines the characteristics and operation of
Ethernet as it has evolved from a shared media, contention-
based data communications technology to today's high
bandwidth, full-duplex technology.
6. Ethernet Operation
LLC and MAC Sublayers
Ethernet –
• Most widely used LAN technology
• Operates in the data link layer and the physical layer
• Family of networking technologies that are defined in the IEEE 802.2
and 802.3 standards
• Supports data bandwidths of 10, 100, 1000, 10,000, 40,000, and
100,000 Mbps (100 Gbps)
Ethernet standards –
• Define Layer 2 protocols and Layer 1 technologies
• Two separate sub layers of the data link layer to operate - Logical
link control (LLC) and the MAC sublayers
8. Ethernet Operation
LLC and MAC Sublayers
LLC
• Handles communication between upper and lower layers
• Takes the network protocol data and adds control
information to help deliver the packet to the destination
MAC
• Constitutes the lower sublayer of the data link layer
• Implemented by hardware, typically in the computer NIC
• Two primary responsibilities:
• Data encapsulation
• Media access control
•
10. Ethernet Operation
MAC Sublayer
Data encapsulation
• Frame assembly before transmission and frame disassembly upon
reception of a frame
• MAC layer adds a header and trailer to the network layer PDU
Provides three primary functions:
• Frame delimiting – identifies a group of bits that make up a frame,
synchronization between the transmitting and receiving nodes
• Addressing – each Ethernet header added in the frame contains the
physical address (MAC address) that enables a frame to be delivered
to a destination node
• Error detection - each Ethernet frame contains a trailer with a cyclic
redundancy check (CRC) of the frame contents
11. Ethernet Operation
MAC Sublayer
Media Access Control
• Responsible for the placement of frames on the media and the
removal of frames from the media
• Communicates directly with the physical layer
• If multiple devices on a single medium attempt to forward data
simultaneously, the data will collide resulting in corrupted, unusable
data
• Ethernet provides a method for controlling how the nodes share
access through the use a Carrier Sense Multiple Access (CSMA)
technology
12. Ethernet Operation
Media Access Control
Carrier Sense Multiple Access (CSMA) process
• Used to first detect if the media is carrying a signal
• If no carrier signal is detected, the device transmits its data
• If two devices transmit at the same time - data collision
14. Ethernet Operation
Media Access Control
The two commonly used methods are:
CSMA/Collision Detection
• The device monitors the media for the presence of a data signal
• If a data signal is absent, indicating that the media is free, the device
transmits the data
• If signals are then detected that show another device was transmitting
at the same time, all devices stop sending and try again later
• While Ethernet networks are designed with CSMA/CD technology, with
today’s intermediate devices, collisions do not occur and the processes
utilized by CSMA/CD are really unnecessary
• Wireless connections in a LAN environment still have to take collisions
into account
15. Ethernet Operation
Media Access Control
The two commonly used methods are:
CSMA/Collision Avoidance (CSMA/CA) media access
method
• Device examines the media for the presence of data signal - if the
media is free, the device sends a notification across the media of its
intent to use it
• The device then sends the data.
• Used by 802.11 wireless networking technologies
17. Ethernet Operation
MAC Address: Ethernet Identity
• Layer 2 Ethernet MAC address is a 48-bit binary value expressed as 12
hexadecimal digits
IEEE requires a vendor to follow two simple rules:
• Must use that vendor's assigned OUI as the first 3 bytes
• All MAC addresses with the same OUI must be assigned a unique
value in the last 3 bytes
18. Ethernet Operation
Frame Processing- 5.1.1.6 Activity - MAC and LLC
Sublayers
MAC addresses assigned to workstations, servers, printers, switches,
and routers
Example MACs: 00-05-9A-3C-78-00, 00:05:9A:3C:78:00, or
0005.9A3C.7800.
Forwarded message to an Ethernet network, attaches header
information to the packet, contains the source and destination MAC
address
Each NIC views information to see if the destination MAC address in
the frame matches the device’s physical MAC address stored in RAM
No match, the device discards the frame
Matches the destination MAC of the frame, the NIC passes the frame
up the OSI layers, where the decapsulation process takes place
19. Ethernet Frame Attributes
Ethernet Encapsulation
Early versions of Ethernet were relatively slow at 10 Mbps
Now operate at 10 Gigabits per second and faster
Ethernet frame structure adds headers and trailers around the Layer 3
PDU to encapsulate the message being sent
Ethernet II is the
Ethernet frame
format used in
TCP/IP networks.
20. Ethernet Frame Attributes
Ethernet Frame Size
Ethernet II and IEEE 802.3 standards define the minimum
frame size as 64 bytes and the maximum as 1518 bytes
Less than 64 bytes in length is considered a "collision
fragment" or "runt frame”
If size of a transmitted frame is less than the minimum or
greater than the maximum, the receiving device drops the
frame
At the physical layer, different versions of Ethernet vary in
their method for detecting and placing data on the media
22. Ethernet Frame Attributes
Introduction to the Ethernet Frame
Preamble and
Start Frame
Delimiter Fields
Used for
synchronization
between the
sending and
receiving devices
Length/Type
Field
Defines the exact
length of the
frame's data field/
describes which
protocol is
implemented
Data and
Pad Fields
Contain the
encapsulated
data from a
higher layer,
an IPv4
packet
23. Ethernet Frame Attributes
Introduction to the Ethernet Frame-5.1.2.4
Activity - Ethernet Frame Fields
Frame Check Sequence Field
Used to detect errors in a frame
with cyclic redundancy check (4
bytes), if calculations match at
source and receiver, no error
occurred.
28. Ethernet MAC
Multicast MAC Address-5.1.3.6 Lab - Viewing
Network Device MAC Addresses
Multicast MAC address is a
special value that begins with
01-00-5E in hexadecimal
Range of IPV4 multicast addresses
is 224.0.0.0 to 239.255.255.255
29. MAC and IP
MAC and IP-5.1.4.4 Packet Tracer - Identify MAC
and IP Addresses
MAC address
This address does not change
Similar to the name of a person
Known as physical address because physically assigned to the host NIC
IP address
Similar to the address of a person
Based on where the host is actually located
Known as a logical address because assigned logically
Assigned to each host by a network administrator
Both the physical MAC and logical IP addresses are required for a
computer to communicate just like both the name and address of a person
are required to send a letter
33. ARP
Introduction to ARP
ARP Purpose
Sending node needs a way to find the MAC address of the
destination for a given Ethernet link
The ARP protocol provides two basic functions:
Resolving IPv4 addresses to MAC addresses
Maintaining a table of mappings
35. ARP
ARP Functions/Operation
ARP Table –
Used to find the data link layer address that is mapped to the
destination IPv4 address
As a node receives frames from the media, it records the source IP
and MAC address as a mapping in the ARP table
ARP request –
Layer 2 broadcast to all devices on the Ethernet LAN
The node that matches the IP address in the broadcast will reply
If no device responds to the ARP request, the packet is dropped
because a frame cannot be created
Static map entries can be entered in an ARP table, but
this is rarely done
42. ARP
ARP Role in Remote Communication
If the destination IPv4 host is on the local network, the
frame will use the MAC address of this device as the
destination MAC address
If the destination IPv4 host is not on the local network, the
source uses the ARP process to determine a MAC address
for the router interface serving as the gateway
In the event that the gateway entry is not in the table, an
ARP request is used to retrieve the MAC address
associated with the IP address of the router interface
43. ARP
Removing Entries from an ARP Table
ARP cache timer removes ARP entries that have not been
used for a specified period of time
Commands may also be used to manually remove all or
some of the entries in the ARP table
44. ARP
ARP Tables on Networking Devices-5.2.1.7
Packet Tracer - Examine the ARP Table
48. Switching
Switch Port Fundamentals
Layer 2 LAN switch
Connects end devices to a central intermediate device on
most Ethernet networks
Performs switching and filtering based only on the MAC
address
Builds a MAC address table that it uses to make forwarding
decisions
Depends on routers to pass data between IP subnetworks
49. Switching
Switch MAC Address Table
1. The switch receives a broadcast frame from PC 1 on Port 1.
2. The switch enters the source MAC address and the switch
port that received the frame into the address table.
3. Because the destination address is a broadcast, the switch
floods the frame to all ports, except the port on which it
received the frame.
4. The destination device replies to the broadcast with a
unicast frame addressed to PC 1.
Continued…
50. Switching
Switch MAC Address Table
5. The switch enters the source MAC address of PC 2 and the
port number of the switch port that received the frame into
the address table. The destination address of the frame and
its associated port is found in the MAC address table.
6. The switch can now forward frames between source and
destination devices without flooding, because it has entries
in the address table that identify the associated ports.
54. Switching
Cut-through Switching-5.3.1.7 Activity - Frame
Forwarding Methods
Two variants:
Fast-forward switching:
• Lowest level of latency
immediately forwards a
packet after reading the
destination address,
typical cut-through
method of switching
Fragment-free switching:
• Switch stores the first
64 bytes of the frame
before forwarding, most
network errors and
collisions occur during
the first 64 bytes
60. Layer 3 Switching
Cisco Express Forwarding
Two main components:
Forwarding information base (FIB)
• Conceptually similar to a routing table
• A networking device uses this lookup table to make
destination-based switching decisions during Cisco
Express Forwarding operation
• Updated when changes occur in the network and
contains all routes known at the time
Adjacency tables
• Maintain layer 2 next-hop addresses for all FIB entries
62. Layer 3 Switching
Types of Layer 3 Interfaces
The major types of Layer 3 interfaces are:
Switch Virtual Interface (SVI) – Logical interface on a switch
associated with a virtual local area network (VLAN).
Routed Port – Physical port on a Layer 3 switch configured
to act as a router port. Configure routed ports by putting the
interface into Layer 3 mode with the no switchport interface
configuration command.
Layer 3 EtherChannel – Logical interface on a Cisco device
associated with a bundle of routed ports.
64. Chapter 5
Summary
Ethernet is the most widely used LAN technology used today.
Ethernet standards define both the Layer 2 protocols and the
Layer 1 technologies.
The Ethernet frame structure adds headers and trailers
around the Layer 3 PDU to encapsulate the message being
sent.
As an implementation of the IEEE 802.2/3 standards, the
Ethernet frame provides MAC addressing and error checking.
Replacing hubs with switches in the local network has
reduced the probability of frame collisions in half-duplex links.
65. Chapter 5
Summary
The Layer 2 addressing provided by Ethernet supports
unicast, multicast, and broadcast communications.
Ethernet uses the Address Resolution Protocol to determine
the MAC addresses of destinations and map them against
known Network layer addresses.
Each node on an IP network has both a MAC address and an
IP address.
The ARP protocol resolves IPv4 addresses to MAC
addresses and maintains a table of mappings.
A Layer 2 switch builds a MAC address table that it uses to
make forwarding decisions.
66. Chapter 5
Summary
Layer 3 switches are also capable of performing Layer 3
routing functions, reducing the need for dedicated routers on
a LAN.
Layer 3 switches have specialized switching hardware so
they can typically route data as quickly as they can switch.
Editor's Notes
Cisco Networking Academy program
Introduction to Networks
Chapter 5: Ethernet