This presentation contains why we need sub netting, how we do sub netting, CIDR, Subnet mask, Subnet mask value, Class A Sub netting, Class B Sub netting, Class C Sub netting.
Network address translation (NAT) is a method of remapping one IP address space into another by modifying network address information in Internet Protocol (IP) datagram packet headers while they are in transit across a traffic routing device.
Overview of Spanning Tree Protocol (STP & RSTP)Peter R. Egli
Ethernet networks require a loop-free topology, otherwise more and more broadcastand unknown unicast frames would swamp the network (creation of frame duplicates resulting in a broadcast storm). Spanning Tree Protocol (IEEE 802.1D) and its faster successor RSTP (IEEE 802.1w) provide loop prevention in bridged networks by establising a loop-free tree of forwarding paths between any two bridges in a network with multiple physical paths. If a link fails, STP and RSTP automatically establishes a new loop-free topology. This presentation describes in detail how STP and RSTP work along with typical examples.
This slide contains the basic and advanced concept of OSPF routing protocol, according to the latest version of Cisco books, and I presented it at IRAN TIC company. In the next slide, I will upload an attractive advanced feature about OSPF.
This presentation contains why we need sub netting, how we do sub netting, CIDR, Subnet mask, Subnet mask value, Class A Sub netting, Class B Sub netting, Class C Sub netting.
Network address translation (NAT) is a method of remapping one IP address space into another by modifying network address information in Internet Protocol (IP) datagram packet headers while they are in transit across a traffic routing device.
Overview of Spanning Tree Protocol (STP & RSTP)Peter R. Egli
Ethernet networks require a loop-free topology, otherwise more and more broadcastand unknown unicast frames would swamp the network (creation of frame duplicates resulting in a broadcast storm). Spanning Tree Protocol (IEEE 802.1D) and its faster successor RSTP (IEEE 802.1w) provide loop prevention in bridged networks by establising a loop-free tree of forwarding paths between any two bridges in a network with multiple physical paths. If a link fails, STP and RSTP automatically establishes a new loop-free topology. This presentation describes in detail how STP and RSTP work along with typical examples.
This slide contains the basic and advanced concept of OSPF routing protocol, according to the latest version of Cisco books, and I presented it at IRAN TIC company. In the next slide, I will upload an attractive advanced feature about OSPF.
Social Business Conference 2013 - Social Media: Become a large platform or ju...HKAIM
Mr. Kaki Chiu
Head of Multimedia Services – Digital & Online Business Unit
New Media Group
Topic: Social Media: Become a large platform or just a small tool for publisher?
In this networking presentation, we have covered NAT and classful Sub netting and classless sub netting using IPv4 address. we find number of hosts,total networks,first valid IP address, Last Valid Ip Address,Host ID,Network ID
CSS L16 - IP ADDRESSING
Learning Competencies
After this learning module the students will be able to . . .
◦○Learn and discuss network addressing, switching and routing.
◦○Identify and understand the IP Addressing format
◦○Understand the explain the Network address translation and IPv6
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
Slack (or Teams) Automation for Bonterra Impact Management (fka Social Soluti...Jeffrey Haguewood
Sidekick Solutions uses Bonterra Impact Management (fka Social Solutions Apricot) and automation solutions to integrate data for business workflows.
We believe integration and automation are essential to user experience and the promise of efficient work through technology. Automation is the critical ingredient to realizing that full vision. We develop integration products and services for Bonterra Case Management software to support the deployment of automations for a variety of use cases.
This video focuses on the notifications, alerts, and approval requests using Slack for Bonterra Impact Management. The solutions covered in this webinar can also be deployed for Microsoft Teams.
Interested in deploying notification automations for Bonterra Impact Management? Contact us at sales@sidekicksolutionsllc.com to discuss next steps.
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
Connector Corner: Automate dynamic content and events by pushing a buttonDianaGray10
Here is something new! In our next Connector Corner webinar, we will demonstrate how you can use a single workflow to:
Create a campaign using Mailchimp with merge tags/fields
Send an interactive Slack channel message (using buttons)
Have the message received by managers and peers along with a test email for review
But there’s more:
In a second workflow supporting the same use case, you’ll see:
Your campaign sent to target colleagues for approval
If the “Approve” button is clicked, a Jira/Zendesk ticket is created for the marketing design team
But—if the “Reject” button is pushed, colleagues will be alerted via Slack message
Join us to learn more about this new, human-in-the-loop capability, brought to you by Integration Service connectors.
And...
Speakers:
Akshay Agnihotri, Product Manager
Charlie Greenberg, Host
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/
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/
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
The field of Information retrieval (IR) is currently undergoing a transformative shift, at least partly due to the emerging applications of generative AI to information access. In this talk, we will deliberate on the sociotechnical implications of generative AI for information access. We will argue that there is both a critical necessity and an exciting opportunity for the IR community to re-center our research agendas on societal needs while dismantling the artificial separation between the work on fairness, accountability, transparency, and ethics in IR and the rest of IR research. Instead of adopting a reactionary strategy of trying to mitigate potential social harms from emerging technologies, the community should aim to proactively set the research agenda for the kinds of systems we should build inspired by diverse explicitly stated sociotechnical imaginaries. The sociotechnical imaginaries that underpin the design and development of information access technologies needs to be explicitly articulated, and we need to develop theories of change in context of these diverse perspectives. Our guiding future imaginaries must be informed by other academic fields, such as democratic theory and critical theory, and should be co-developed with social science scholars, legal scholars, civil rights and social justice activists, and artists, among others.
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
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
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
"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.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
FIDO Alliance Osaka Seminar: Passkeys at Amazon.pdf
How IP address works
1. TCP/IP Addressing Demystified
- Edited by Alien Coders
Team
Contributed by Souvik
Official Website: http://www.aliencoders.com
Facebook Page: https://www.facebook.com/aliencoders
2. What you will learn
• How internet addressing works
• Internet Addressing
• Role played by Routing and addressing
• ARP
• TCP/UDP
• IPv6 into the picture
3. • The Internet Protocol (IP) enables communications across a vast and
heterogeneous collection of networks.
• The Internet offers two basic communication services that operate on
top of IP:
• TCP Transmission control protocol i.e reliable stream service.
• UDP User datagram Protocol.
4. The TCP header contains the port number of the client process and the well
known port 80 for the HTTP server process.
The IP network address are the logical address because they are defined in terms
of logical topology of the routers and the end systems.
Ethernet LAN frames contains physical address that identify the physical
endpoints for the sender and the receiver.
5. • The network interface layer is particularly concerned with the
protocols that are used to access the intermediate networks.
• At each gateway the network protocol is used to encapsulate the IP
packet into a packet or frame of the underlying link.
• The router must determine the next hop in the route to the
destination and then encapsulate the IP packet or frame of the type of
the next network or link
7. • Total Length : With 16 bits , the max packet
length = 65,535
• Protocol TCP =6 ; UDP =17 ; ICMP = 1
• Options : Security level , Route to be taken by the
packet
• Padding : To make the header field a multiple of
32 bit word.
8. Internet Addressing
Network Host
An IP address is divided into 2 parts:
a) network part 2) host part .
The part of a public IP address that identifies the network is
internationally controlled by the Network Information Center (NIC)
located in the Stanford Research Institute in California.
The part that identifies the host is controlled locally at a
network level.
9. Internet Addressing
An Internet address is four octets (i.e. 32 bits) long.
The first few bits in the network part of the address helps interpret the
address.These bits indicate the class of the address.
When a system wants to communicate over the internet they need to have a
public address.
This public address has to be purchased from NIC in Stanford.
10. Address classes
There are five Internet address classes. They are : Class A / B / C / D / E .
Class A addressing is used for very large networks, that is networks which will
have a large number of hosts attached to them.
For class A the MSB is 0.
Each pure class A network can support (224-2) hosts. One address each being
reserved for network address (all 0 ) and all one for broad cast.
11. Class A
Host ID
24 bits
The first bit is 0 and next 7 bits called the Net ID identifies
the network . The next field contains the host ID, which
identifies the particular host within the specified network.
In a class A address it's 24 bits long and therefore allows
for almost 17 million hosts on a network.
For example 10.200.20.5 is a class A address
12. Class B
Class B addressing is used for medium-sized networks.
If the first two bits in the address are 10, it's a class B address. 14 bits for network Ids
and 16 bits for host Ids allowing about 16,000 networks and 64,000 hosts for each
network.
The range of first octet of class B address is 128 –191.i.e 128.0.0.0 to 191.255.0.0
13. Class C
The next address class is class C, probably the most common network class.
If the first 3 bits in the address are 110, the address is a class C address.
The net ID is 21 bits long and the host ID is 8 bits long, allowing about 21
million networks and 254 hosts per network.
The range of class C Network is 192.0.0.0 – 223.255.255.0
The 192.0.0.2555 is the broadcast address and 192.0.0.0 is the network
address.
14. Class D
Class D addressing is used for multicasting a number of hosts for applications
like audio and video conferencing.
Class D networks have the first 4 bits in the network part = 1110.
The first octet ranges from 224 – 239.
All the addressees from 224.0.0.0 to 239.255.255.255 can be used as multicast
address.
16. • A host ID that contains all 1s is meant to broadcast the
packet to all hosts specified by the network.
• If the network ID also contains all 1s the packet is
broadcast on the local network.
• A host ID that contains all 0s refers to the network
specified by the network ID , rather than to a host.
• A source may send all 0s in the source address while
trying to find out the correct IP address. The machine is
then identified by its MAC address.
17. • These are the IP address ranges reserved for private
networks within organizations.
• These addresses will not be allocated by NIC as public IP
address for the internet.
• There is no problem of clash because when a packet goes
outside the organization the local IP address gets translated
into into the public IP address purchased by the
organizations.
18. Private Addressing
– Class A:
• 10.0.0.0 to 10.255.255.255---- 1 Class A network
– Class B:
• 172.16.0.0 to 172.31.255.255 ---- 16 contiguous Class B
networks
– Class C:
• 192.168.0.0 to 192.168.255.255--- 255 contiguous Class C
networks
19. • These are IP address ranges reserved for private networks
within organizations.
• These addresses will not be allocated by NIC as public IP
addresses for the Internet.
• There is no problem of clash because when a packet goes
outside the organization the local IP address gets translated
into the public IP address purchased by the organization.
20. Reserved and Available IP
Addresses
Class Address or Range Status
A 0.0.0.0 Reserved
1.0.0.0 through 126.0.0.0 Available
127.0.0.0 Reserved
B 128.0.0.0 Reserved
128.1.0.0 through 191.254.0.0 Available
191.255.0.0 Reserved
C 192.0.0.0 Reserved
192.0.1.0 through 223.255.254 Available
223.255.255.0 Reserved
D 224.0.0.0 through Multicast group
239.255.255.255 addresses
E 240.0.0.0 through Reserved
255.255.255.254 Broadcast
255.255.255.255
21. • Subnet Addressing : To add another
hierarchical level called the subnet .
• The beauty of the subnet addressing scheme is
that it is oblivious to the network outside the
organization.
22.
23. • An organization has many LANs , each consisting of no more than
100 hosts.
• 7 bits for for host identification in a sub network and other 9 bits are
used for identifying the subnetwork.
• Packet with destination IP 150.100. 12.176 arrives
• The subnet mask used is 11111111 11111111 11111111 10000000 =
255.255.255.128
• The router performs the AND between the subnet mask and the IP
and the subnet number becomes 10010110 01100100 00001100
10000000 : 150.100.12.128
This number is used to forward the packet to the correct subnetwork.
24. IP Address Classes Exercise
Address Class Network Host
10.2.1.1
128.63.2.100
201.222.5.64
192.6.141.2
130.113.64.16
256.241.201.1
0
25. IP Address Classes Exercise
Answers
Address Class Network Host
10.2.1.1 A 10.0.0.0 0.2.1.1
128.63.2.100 B 128.63.0.0 0.0.2.100
201.222.5.64 C 201.222.5.0 0.0.0.64
192.6.141.2 C 192.6.141.0 0.0.0.2
130.113.64.16 B 130.113.0.0 0.0.64.16
256.241.201.1
Nonexistent
0
26. Subnet Mask
Network Host
IP
Address
172 16 0 0
Network Host
Default
Subnet
Mask
255 255 0 0
11111111 11111111 00000000 00000000
Also written as “/16” where 16 represents the number
of 1s in the mask.
Network Subnet Host
8-bit
Subnet 255 255 255 0
Mask
Also written as “/24” where 24 represents the number
of 1s in the mask.
42. 192.168.9
1.4
192.1
192 Laye 68.89
.20
.168.
90.3 r2
Rout Rout
er C er A
Rout 192.1 192.1
er B 68.89
192 .2 68.89
.40
.168.
91.3
ARP
192 192.168.
.168. 88.2
90.2
192.1
Laye 6
r
8.88.
2 20
19 2.168
.88 .40
Routing Demonstration
43. Routing done by Host
Network Netmask Gateway Interface
Destination
0.0.0.0 0.0.0.0 192.168.88.2 192.168.88.40
192.168.88.0 255.255.255.0 192.168.88.4 192.168.88.40
0
192.168.88.40 255.255.255.25 127.0.0.1 127.0.0.1
5
Let assume IP packet received by network layer of
host have destination IP 192.168.88.20 and source IP: 192.168.88.40
192.168.88.20 192.168.88.20
AND AND
255.255.255.255 255.255.255.0
192.168.88.20 192.168.88.0
44. Routing done by Host
Network Netmask Gateway Interface
Destination
0.0.0.0 0.0.0.0 192.168.88.2 192.168.88.40
192.168.88.0 255.255.255.0 192.168.88.4 192.168.88.40
0
192.168.88.40 255.255.255.25 127.0.0.1 127.0.0.1
5
Let assume IP packet received by network layer of
host have destination IP 192.168.89.4 and source IP: 192.168.88.40
192.168.89.4 192.168.89.4 192.168.89.4
AND AND AND
255.255.255.255 255.255.255.0 0.0.0.0
192.168.89.4 192.168.89.0 0.0.0.0
45. Routing Done Router A
Network Netmask Gateway Interface
Destination
0.0.0.0 0.0.0.0 192.168.90.3 192.168.90.2
192.168.88.0 255.255.255. 192.168.88.2 192.168.88.2
0
192.168.89.0 255.255.255. 192.168.89.2 192.168.89.2
0
192.168.90.0 255.255.255. 192.168.90.2 192.168.90.2
Let assume IP packet received by layer 3
0
have destination IP 192.168.89.4 and source IP: 192.168.88.40
192.168.91.0 255.255.255. 192.168.90.3 192.168.90.2
192.168.89.40
AND
255.255.255.0
192.168.89.0
46. Routing Done by Router B
Network Netmask Gateway Interface
Destination
0.0.0.0 0.0.0.0 192.168.91.4 192.168.91.3
192.168.88.0 255.255.255.0 192.168.90.2 192.168.90.3
192.168.89.0 255.255.255.0 192.168.90.2 192.168.90.3
192.168.90.0 255.255.255.0 192.168.90.3 192.168.90.3
192.168.91.0 255.255.255.0 192.168.91.3 192.168.91.3
Let assume IP packet received by Router A
have destination IP 192.168.92.5 and source IP: 192.168.88.40
192.168.92.5 192.168.92.5
AND AND
255.255.255.0 0.0.0.0
192.168.92.0 0.0.0.0
47. Dynamic Routing
Routing Protocol
Interior Gateway Protocol Exterior Gateway Protocol
Open Shortest Path First Routing Information Protocol
Border Gateway Protocol
Dijkstra Algorithm Bellman Ford Algorithm
Link State Protocol Distance Vector Protocol
48. Address Resolution Protocol
• The address resolution protocol (ARP) is used when
one host wants to get the physical address of
another host on the same network.
An IPv4 or IP Version 4 address consists of 4 bytes or 32 bits. The IP address is divided into the network part and the host part. The number of bits occupied by the network part and the host part depends on the class of the network. Networks are broadly divided into 3 classes: Class A Class B Class C When sytems want to communicate over the internet they need to have a public IP address. This public IP address is unique for each system on the Internet. This public address has to be purchased from the Network Information Center (NIC) in Stanford. Systems inside a coorporation or cahbmpus can use private IP addresses to communicate to each other. These need not be purchased from NIC.
We can identify the class of the network from the IPv4 address by examining the first bits of the IP address. For Class A first or Most Significant Bit(MSB) is 0. For Class B the first bit is 1 and second bit is 0 ie first two bits = 10 For Class C the first and second bits are 1 and the third bit 0 , first three bits =110 Each byte of the IP address is represented as a decimal integer and the 4 bytes of the IP address are separated by dots( . ) for human ease of readability. For example 10.200.20.5 is a Class A IP address because the first byte “10“ has a bit pattern 00001010. So 1 st bit is 0 making it a Class A address. Similarly 129.4.4.5 is a Class B address as 129 has bit pattern 1000 0001 So 1 st 2 bits are 10 making it Class B. Class C is similar Anything in the range 192 to 239 in the first byte is a Class C Address as the first 3 bits would be: 110
In a Class A network the network part consists of the 1 st 8 bits, the remaining 24 bits are for the host part. So each pure Class A network can support (2 24 - 2) hosts . The reduction by 2 is due to one address each being reserved for the network address(all 0s in the host part) and broadcast address for the network(all 1’s in the host part) A pure Class A network cannot be used in practice. If at all it is used the number of hosts in the Class A network would be very much less than the maximum possible. Typically 30 – 254 is the optimum number of hosts possible on any network for transmission and reception to take place without collisions. So a Class A network would have to be divided into smaller networks called subnets. This is achieved by using the first bits in the host part to represent the address of the subnet. Each subnet now can operate independently of the others. Depending on the number of bits used for subnetting or dividing the original Class A network the number of hosts per subnet would correspondingly reduce.
The first octet or digit in a Class A Network representation can vary from 0 to 127. 0 is reserved for representation of default route(0.0.0.0) 127 is reserved for loopback ( 127.0.0.1) Loopback address is the address used to loop back a packet within the ip stack without going out of the network card. Loopback is used for testing and for accessing applications locally through the ip layer. So the available addresses in Class A range from 1 to 126. Of these 10 is reserved as a private IP network prefix address to be used in organizations. For example Wipro uses 10.0.0.0 to 10.255.255.255 as the range of its local IP network, host and broadcast addresses in this range. So too do other organizations.
The range of the 1 st octet or byte of a Class B address is therefore: 128 to 191 Class B network part has 16 bits. So Class B network addresses range from: 128.0.0.0 128.1.0.0 … .. 128.255.0.0 129.0.0.0 … .. 129.255.0.0 … . 191.0.0.0 … . 191.255.0.0 Remember 0.0 in the last 2 bytes corresponds to a network address.
Since the 1 st 3 bits in the network part of a Class C address is 110, The range of Class C network adddresses is: 192.0.0.0 192.0.1.0 .. 192.255.255.0 … .. 223.255.255.0 Remember that Class C has 24 bits in the network part and 8 bits in the host part. The broadcast address for the 192.0.0.0 network is 192.0.0.255 Here all the last 8 bits, the host part, are 1s. Class C networks and Class B networks just like Class A networks can be subnetted or divided into smaller subnets. The maximum number of hosts in a Class C network is 256 -2 = 254. The Class C network 192.0.0.0 has host addresses in the range: 192.0.0.1 to 192.0.0.254 . Note 192.0.0.25 is broadcast address and 192.0.0.0 is the network address.
Class D networks are used for multicasting or group addressing for applications like audio and video conferencing over IP networks. Class D networks have the 1 st 4 bits in the network part = 1110 So the first octet or byte ranges from 224 to 239. There is no other interpretation of the remaining part. All the addresses from 224.0.0.0 to 239.255.255.255 can be used as multicast addresses. Some of the addresses in the 224 range are reserved for special purposes like OSPF multicast messages amongst routers. The process of multicasting involves registration of a client to a multicast server for joining a multicast group. The multicast server allocates a multicast group address to which the client now belongs. This multicast address can be used for communication amongst the group. Any ip packet with the multicast ip address will be delivered to al members of the group.
Multicasting can also be enabled on routers so that multicast groups can span different networks or subnetworks(subnets). The multicast IP address determines the multicast MAC address. The last 23 bits of the multicast ip address of a group a client belongs to is appended to a fixed value in the 1 st 25 bits of the MAC address. 1 st 24 bits in MAC address for multicasting is: 01:00:5e followed by the 25 th bit as 0. After this the last 23 bits of IP address is added to form the MAC multicast address. For example if Multicast IP address is : 224.9.10.11 the last 23 bits are 09:0a:0b with a 0 bit added in front( Note 10 is “0a” in hex and 11 is “0b” in hex.) The fixed part being 01:00:5e the MAC address corresponding to 224.9.10.11 multicast IP address is: 01:00:5e:09:0a:0b Suppose the multicast IP address is 224.1.2.3 the corresponding Multicast MAC address is 01:00:5e:01:02:03
These are the IP address ranges reserved for private networks within organizations. These addresses will not be allocated by NIC as public IP addresses for the Internet. The Class A private addresses are in range 10.0.0.0 to 10.255.255.255 Which means there are 2 24 addresses approximately available. Of course due to subnetting some ip addresses will be lost for subnet ip addresses and subnet broadcast addresses. All organizations be it Wipro, TCS . IBM or Microsoft use this range of addresses. There is no problem of clash because when a packet goes outside the organization the local ip adress gets translated into the public IP address purchased by the organization. In Class B a lesser number of addresses in range 172.16.0.0 to 172.3.255.255 is available. In Class C anything starting with 192.168 is a private IP address. Private IP address allocation is a good example of reusability. Service providers allocate private ip addresses to connected Home or Small Office subscribers( SOHO..SmallOffices and Homes)
This is the complete range of Reserved and Available IP addresses As mentioned 0.0.0.0 is reserved for default routing address. Anything starting with 127 is reserved for loopback. Some other addresses like 128.0.0.0, 191.255.0.0, 192.0.0.0 and 223.255.255.0 are reserved by NIC for its own use. Of course addresses stating with 10, 172.16 to 172.31 and 192.168 are reserved for private addressing. 255.255.255.255 is used for broadcasting to local subnet.
Find the Class, Network Address and the host part of each of these addresses.
172.16.0.0 is a pure Class B network address. For this network all hosts will have the same common 1 st 16 bits corresponding to 172.16 This is also represented as a subnet mask. The subnet mask for a pure Class B network also called the default subnet mask for a Class B network is 255.255.0.0. This means that the 1 st 16 bits of all hosts on the same network will be the same ie if a host in the Class B network 172.16.0.0 with IP address say 172.16.1.1 has its IP address anded bitwise with the subnet mask 255.255.0.0 ( 1 st 16 bits 1 and remaining 16 bits 0) then the result of the anding operation will be the network address 172.16.0.0 All hosts on the network 172.16.0.0 will have network part same 172.16, the host part will be different. The subnet mask is giving the information as to how many bits in the ip address is common for the hosts on a network or subnet. In other words all hosts on a pure Class A.B or C network or its subnets will have the same value in the bits corresponding to 1s in the subnet mask for the network or subnet This also logically implies that every network or subnet will have its own subnet mask which is characteristic of that network or subnet. Subnets are derived from pure ClasA, Class B or Class C networks.
This figure explains how subnet masks are converted to decimal addresses. It sometimes is useful to remember them. One possible view of logical AND is as follows: We will need to be able to perform a logical AND on the binary numbers. Just take two binary numbers and place one above the other. The ones in the bottom are like a pipe—the number above it just drops through. The zeros are like a clogged pipe, so nothing comes out in the answer.
Here default subnet mask is used for pure Class B network without subnetting
This example makes a Class B address space look like a collection of Class C address spaces. This is because we are subnetting a Class B Network 172.16.0.0 using 8 more bits for subnetting. So the subnet mask becomes 255.255.255.0 which is the same as the default subnet mask for a pure Class C network. Now the logical AND allows us to extract the subnet number as well as the assigned network number. The subnet number is from bits 17-24 counting the most significant bit as bit 1. The subnet address however will be 172.16.2.0 which includes the pure Class B network part 172.16 and the subnet number 2
Here we are splitting up the Class B network 172.16.0.0 into 1024 subnets ( 2 10 = 1024) So the subnet mask is 255.255.255.192 ( Totally 26 1s followed by 6 0s. No of 1s 10 more than in default subnet mask for Class B , which is 16 1s followed by 16 0s)
A range of addresses is needed to allocate address space. A valid range of addresses is between subnet zero and the directed broadcast. These RFCs provide more information about broadcasts: RFC 919, Broadcasting Internet Datagrams RFC 922, Broadcasting IP Datagrams in the Presence of Subnets Cisco’s support for broadcasts generally complies with these two RFCs. It does not support multisubnet broadcasts that are defined in RFC 922. Typically routers nowadays will not support broadcast to mu;tiple subnetsto prevent unnecessary wastage of bandwidth. In fact in IPv6 (Version 6) there is no broadcast at all, only multicasts and unicasts
Convert the given address address to a binary host address.
Write the subnet mask in binary.
Draw a line at the end of the ones in the subnet mask.
Fill in zeros beyond the vertical line for getting the subnet address of the subnet the given IP address is a part of.
Fill in ones beyond the vertical line for the broadcast address for this subnet.
Fill in 0s beyond the vertical line except for the last bit. Make that bit a 1. This is the first usable host address in the given subnet.
Fill in 1s beyond the vertical line except for the last bit. Make that bit a 0. This is the last usable host address in the subnet.
Alternative Method: Step 1: Take the subnet mask Here it is 255.255.255.192 Step 2: Find the first octet in subnet mask which is not 255 Here it is the last octet, 192 Step 3: Subtract this value from 256 Here 256 -192 = 64. Now 64 is the difference between successive subnet addresses in this octet. Step 4: Find between which subnet addresses the given IP address falls. then take the lower subnet address of the two as the subnet address of the subnet the IP address belongs to Here the subnet addresses in 4 th octet are: 172.16.2.0 172.16.2.64 172.16.2.128 172.16.2.192 2 bits used in 4 th octet , so 4 subnets will lie in 4 th octet.
The Network layer is concerned with getting packets from the source to the destination. That is it is in charge of routing the packets along the best possible path. The process of routing takes place at each intermediate router along the path. In this typical network topology, Subnet 192.168.88.0 has 2 hosts shown in figure connected to the Layer 2 switch. These are hosts 192.168.88.40 and 192.168.88.20. Moreover the bottom most interface of Router A is also connected to the same switch and is also on the same subnet with an IP address of 192.168.88.2 as shown in diagram. Similarly the 192.168.89.0 subnet connected through another Layer 2 switch has 2 hosts( 192.168.89.40 and 192.168.89.20) and the router A’s top interface 192.168.89.2. Router A has a 3 rd interface with IP address 192.168.90.2 on the 192.168.90.0 subnet. So Router A is the junction of 3 subnets: 192.168.88.0, 192.168.89.0 and 12.168.90.0 Similarly router B connects 2 subnets 192.168.90.0 and 192.168.91.0. Router C is connected to 192.168.91.0 subnet and another subnet on its other interface which is not specified in the diagram. As can be seen Routers are connected to each other through a common subnet.
This is the route table on the host with IP address 192.168.88.20 If you want to see the route table on a Windows machine, At the command prompt type: C:>route –print The route table will be displayed similar to shat is shown above. IF you see the botommost entry in the table this corresponds to the ip address of the same machine. So the subnet mask is all 1s ie 255.255.255.255. So first when the ip layer receives a packet from the higher layer it tries to find a match with this subnet mask. Basically matching occurs in the order of the length of 1s in the subnet mask, the longest 1s order subnet mask being processed first and so on. Note that the entry for this bottom row has Outgoing interface entry as 127.0.0.1 which coresponds to loopback interface.
This example shows how packets to other networks will be routed through the gateway Router A for host 192.168.88.40
This is the Routing Table for Router A. Router A has 3 directly connected subnets: 192.168.88.0 192.168.89.0 192.168.90.0 So there are 3 entries or rows corresponding to these 3 subnets. For these directly connected subnets, ie rows 2,3 & 4, the Gateway IP column and the Interface column will be the same, ie the ip address of the interface of Router A directly connected to the subnet. Those 3 interfaces are respectively: 192.168.88.2 on 192.168.88.0 subnet 2. 192.168.89.2 on 192.168.89.0 subnet 192.168.90.2 on 192.168.90.0 subnet
Router B has 2 subnets directly connected, 192.168.90.0 and 192.168.91.0 There are same number of rows 5 as in router A. 4 correspond to the 4 different subnets shown in the topology and 1 is for default route. Typically in the simplest scenario the number of rows or entries in the routing table of each router will be the same as the number of subnets in the whole network excluding the default route entry. In this toplolgy there will be 5 rows in each of the routers A,B & C.
Routing Protocols are used by Routers to exchange their routes with each other. There are 2 types of Routing Protocols: Interior Gateway Protocols Exterior Gateway Protocols Interior Gateway Protocols are used within the private intranet of an organization. Exterior Gateay protocols are used by one organization to communicate and find out routes to other organizations. For example Exterior Gateway protocol would be necessary for Wipro Mail Server to talk to Infosys or TCS mail server and vice versa. For communication within Wipro only Interior Gateway Protocols between the Routers in Wipro intranet is used. Interior Gateway Protocols can be of different types.
As a packet is sent down through the network layers, routing determines the protocol address of the next hop for the packet and on which piece of hardware it expects to find the station with the immediate target protocol address. In the case of the Ethernet, address resolution is needed and lower layer must consult the Address Resolution module to convert the <protocol type, target protocol address> pair to a 48.bit Ethernet address. The Address Resolution module tries to find this pair in a table. If it finds the pair, it gives the corresponding 48.bit Ethernet address back to the caller (hardware driver) which then transmits the packet.
An ARP message, which contains the Internet address of the host you want the physical address of, is broadcast to all the hosts on the network. Only the host which recognizes its own IP address will respond by sending its physical address back to the transmitting host. All the other hosts will ignore the ARP broadcast. The transmitting host can now store this information for later use.
In order to deliver a datagram to another host on the same network, the transmitting host maps the Internet address onto the physical address. Therefore, if the transmitting host only knows the Internet address of the receiving host, it must have some means of getting its physical address.