Understanding Key Network Protocols: ARP, BOOTP, ICMP, IP, RARP

Key Network Protocols Explained

4. ARP Protocol Functionality

The ARP (Address Resolution Protocol) is crucial for TCP/IP networks. It resolves IP addresses to physical MAC addresses, enabling communication on Ethernet networks. A machine needs both the MAC and IP address to send a message. If the MAC address is unknown, a broadcast message is sent, and the owner of the IP address responds with its MAC address.

5. BOOTP Protocol Information

BOOTP (Bootstrap Protocol) is a UDP network protocol that allows

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Understanding the Session Layer: Communication Protocols

Session Layer: Communication Protocols and Synchronization

The first problem is that your messages can be crossed during the conversation. Both of you can type messages at exactly the same time, interrupting each other. The second problem is the need to stop (to save the current conversation as a file) or verify the previous conversation of each (to get clues of the reason for discussion) or to resynchronize the communication after a break.

  • To solve the first problem, you should establish a protocol
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Understanding the Internet: Key Terms and Concepts

Unit 5: The Internet – Key Definitions

These are the definitions and concepts of Unit 5, Item 4 of the book, pp. 94, 95. Each definition is written as simply and briefly as possible, followed by some clarifications for better understanding. I hope this helps you.

Internet

A worldwide network of computers that emerged from the interconnection of thousands of local networks worldwide through routers and gateways. The various interconnected networks are highly heterogeneous, i.e., different in nature,

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Transport Layer: Congestion Control, Flow Control, TCP & UDP

What is Congestion Control in the Transport Layer?

Congestion control is an algorithm used in TCP that reacts to certain events occurring in the network. It sends packets without reservation, preventing packet loss in a router. It involves increasing the transmission rate, testing the available bandwidth until leakage occurs.

What is Flow Control in the Transport Layer?

Flow control is an algorithm that prevents the sender from overflowing the receiver’s buffer by transmitting data too quickly. The

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Effective Information Gathering Techniques for Businesses

Information Gathering

Business

Collect:

  • crunchbase.com or www.inc.com
  • Cached and archived sites: archive.org, Google (cache: URL)

Financial

  • Harvesting (emails, files, PDFs, etc.):

CASE I

  • theHarvester -d site -l 100 -b google
  • ORG (domain): Google (site: filetype:)

Social Media

  • People: LinkedIn, site:, www.pipl.com, Spokeo, People Finders, Crunchbase

Infrastructure

  • Domains, Netblocks or IPs, MX, ISPs, etc.
  • Whois – owner, DNS, MX, Exp

DNS Enumeration

  • DNSdumpster, DNSenum, DNSmap
  • nslookup site
  • rev – nslookup -type=PTR
  • nslookup
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Network Protocols and the OSI Model Explained

Network Protocols

A protocol is a set of rules that enable the transfer of data between two or more computers.

Level Architecture

The purpose of the level architecture is to reduce the complexity of logically grouping data communication functions in certain areas of responsibility (levels).

Features

Each level provides services to the upper level and receives services from the lower level.

A message from a top level contains a header with information to be used in the receiving node.

The set of services

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