Introduction to Network Fundamentals

Network fundamentals and terminology

Components of a network: devices, media, network adapter, network operating system

Node types: endpoint nodes and redistribution nodes

Server definition and responsibilities

Network backbone and its variations

Terminal, client, and peer definitions

Network categories: LAN, WAN, MAN, PAN, CAN, GAN

Internet, intranet, and extranet explanations

Centralized, client-server, peer-to-peer, and mixed mode network models

Different types of network topologies: bus, star, ring, tree, and mesh.

Hybrid topologies combine aspects of multiple topologies.

Logical topology describes how data is communicated while physical topology refers to how devices are physically connected.

🔑 Cat5 and Cat5e cabling provide performance of up to 100 megabits per second with a maximum distance of 100 meters.

🕹️ Cat6 increased the transmission speeds to one gigabit per second, while Cat6a could achieve up to 10 gigabits per second.

🔌 Cat7, a newer implementation, supports a signaling rate of one gigahertz and has the potential for over 10 gigabits per second.

Different standards for cabling on each end: A standard and B standard

Auto MDIX allows devices to automatically detect and adjust for different cable types

Rollover cable used for connecting PC or laptop to console port on router or switch

Switches and routers are connectivity devices used in networks. Switches use MAC addresses while routers use IP addresses to forward data.

Multi-layer switches can operate at multiple layers of the OSI model, and can switch frames based on MAC addresses or route IP addresses.

Gateways connect networks with different protocols, translating incompatible networks, email systems, or operating systems.

Virtualization has become an important aspect of computing, allowing for virtual switches, servers, machines, and desktops.

Network as a Service (NaaS) allows organizations to lease their network infrastructure to others as a service.

Legacy devices like repeaters, hubs, and bridges have been replaced by more advanced networking devices, such as switches and routers.

Noise in networking can come from various sources, such as power lines, electric motors, and high-intensity discharge lights.

Noise control techniques, such as proper grounding and shielding, are implemented to improve network performance and prevent interference.

📶 Analog signals carry data in a continuous waveform and have various attributes.

💻 Digital signals transmit data using voltage and have specific reference methods for timing.

🔀 Modulation allows for the transmission of digital signals over long distances.

📊 Digital data units, such as kilobytes and megabytes, measure the amount of data transmitted.

Differences in computer networks are represented by ones and zeros.

Digital signals use voltage to represent ones and zeros.

Different encoding schemes are used to transmit digital signals.

Modulation is the process of superimposing a weaker analog signal on a stronger carrier signal.

Digital modulation allows digital signals to travel long distances.

Different methods of modulation and demodulation are used in digital signal transmission.

Different digital data units and measurements are used in computer networking.

Network protocols and services use specific ports and protocols for communication.

Interoperability services allow different systems to communicate and share resources.

Specific interoperability services include NFS, SSH, SCP, Telnet, SMB, LDAP, and Zeroconf.

The video discusses the OSI model, which is a layered approach to network communication.

Layer 1, the physical layer, deals with the physical media used for communication, such as cables and wireless connections.

Layer 2, the data link layer, handles error detection, access control, and MAC addressing. Switches operate at this layer.

Layer 3, the network layer, is responsible for routing data between devices on different networks. Routers operate at this layer.

ARP is a protocol that maps MAC addresses to IP addresses.

The network layer is connectionless and manages data transfer without waiting for a reply.

The transport layer ensures reliability, flow control, and sequencing of data.

The session layer establishes and maintains communication sessions.

The presentation layer translates data into a format that the rest of the network can understand.

The application layer provides utilities and services for accessing network resources.

The TCP model is a widely used networking model that defines how data flows in a communication system.

The internet protocol is responsible for fragmentation, which divides data into smaller manageable blocks for transmission.

A black hole router occurs when a datagram is sent with an MTU greater than the receiving device's MTU, resulting in data loss.

The network interface layer handles the physical transfer of bits and is responsible for data link and network access control.

TCP is a reliable protocol that guarantees data delivery and integrity, while UDP is a connection-less protocol that prioritizes speed over reliability.

IP is a connection-less protocol used for routing and host identification, and it is essential for connecting to the internet.

ARP is a protocol used to map IP addresses to MAC addresses, and it is necessary for TCP/IP communication.

ARP and RARP are important protocols for network communication.

ICMP is used for system status messages and diagnostic purposes.

IGMP is used for establishing memberships in multicast groups.

🔑 IPv6 is the successor to IPv4 and offers several improvements, including an increase in the number of possible addresses, enhanced security, simplified headers, and support for time-sensitive traffic.

📶 IPv6 uses a 128-bit binary address, allowing for a much larger address space compared to the 32-bit address used in IPv4.

🌐 IPv6 provides hierarchical addressing for easier routing and supports time-sensitive traffic such as voice over IP and gaming.

🌐 IPv6 has a much larger addressing scheme compared to IPv4, with 128-bit addresses divided into eight groups of 16 bits.

🔒 IPv6 has security features built-in, including a field in the packet for security purposes, while IPv4 lacks these features.

📱 IPv6 is designed to work well with mobile devices, offering plug-and-play configuration and better support for cellular networks.

📚 DNS is the system that resolves domain names to IP addresses.

💻 Domains are the names of computers with an IP address on the internet.

🌐 DNS allows multiple domain names to share the same IP address.

There are five simple TCP/IP services: character generation, daytime service, discard service, echo service, and quote of the day service.

Character generation is used for generating characters, often for printer testing.

Daytime service provides information about changes or errors in a system's internal clock.

Discard service automatically discards unimportant messages that enter its port.

Echo service sends an exact copy of any message it receives to be monitored.

Quote of the day service sends a short message selected by the administrator to a client's device.

The video discusses the importance of time zones and the format of timestamps in emails.

The video explains the TCP simple services, which include character generator, daytime service, discard service, echo service, and quote of the day.

The video introduces essential TCP/IP tools such as Ping command, trace route command, protocol analyzer, port scanner, NS lookup, ARP command, and route command.

The video provides an overview of LAN administration and implementation, including the setup of servers, network topography design, backups, documentation, auditing, troubleshooting, and security.

The video explains the function of an Ethernet switch in a local area network (LAN), allowing data to flow between devices based on their MAC addresses.

The video mentions advanced switches like multi-layer switches and content switches, which have additional capabilities.

📡 A router connects two networks together and allows for data to travel between them by reading the information in a packet's header and determining the destination.

🛣️ Routing tables in routers contain information on how to route packets to their destinations based on IP addresses.

⚙️ Static routing involves manually adding routes to routing tables, while dynamic routing automatically updates routing tables as network structures change.

A router has a routing table that maps IP addresses to Mac addresses and determines the routes to take.

Static routing involves manually updating the routing table to specify routes.

Dynamic routing protocols, such as OSPF and BGP, automatically update the routing table based on network changes.

Wide Area Networks (WANs) connect multiple local area networks (LANs) over a large geographic area.

WANs can be implemented using virtual private networks (VPNs) to create a secure connection over the internet.

WAN administrators are responsible for tasks such as backups and security to protect the network.

WAN transmission technologies include ISDN, T carrier, Sonet, x25, frame relay, and ATM.

💡 ISDN and T carrier lines are examples of WAN connectivity options.

📡 Packet switching and circuit switching are two types of switching used in WANs.

🔒 Circuit switching provides a dedicated and secure connection, while packet switching allows for faster transmission but with a higher chance of data loss.

📶 ATM and cell relay are transmission technologies used in WANs to break data into smaller cells for efficient transfer.

☎️ Voice over IP (VoIP) allows for phone calls to be made over the internet or ethernet network instead of traditional phone systems.

📡 Remote access allows users to connect to a network from a different location using various methods like RDP, SSH, VNC, Telnet, and HTTPS.

🔒 Security measures like encryption and authentication protocols are essential for remote access to ensure secure connections.

🌐 Remote access enables flexibility in working remotely and accessing corporate resources from anywhere in the world.

The video discusses different methods of remote access such as VNC, Telnet, and HTTPS management.

It explains the concept of VPNs and the different protocols used, such as PPTP and L2TP.

The video also covers the role of network administrators and their responsibilities, including documentation and network monitoring.

Network security is important to keep threats out and valuable data in.

Fundamentals of network security include keeping the network up to date, using strong passwords, using a secure VPN, managing user access properly, and removing inactive accounts.

Keeping programs and patches up to date is crucial to prevent attackers from exploiting known vulnerabilities.

Using strong passwords is essential to protect against unauthorized access.

🔒 Using different passwords for different services is crucial to protect your personal information.

🔑 Creating strong and complex passwords using a combination of numbers, symbols, and letters is important.

🌐 Utilizing virtual private networks (VPNs) and multiple forms of authentication adds an extra layer of security.

🔥 Having firewalls and antivirus software in place helps protect against attacks from outside sources.

🔐 Encrypting data and using cryptography techniques ensure secure communication and prevent unauthorized access.

Denial of service attacks aim to make network services unavailable to legitimate users by flooding the network with excessive traffic or requests.

There are different types of denial of service attacks, including bandwidth attacks, connectivity attacks, and buffer overflow attacks.

Denial of service attacks can disrupt website access, email services, or target specific devices or programs.

Mitigation is essential in protecting a network from attacks by reducing the frequency and impact of attacks.

Developing strong security policies, monitoring threats, and educating users are key steps in a mitigation strategy.

Users should be educated on recognizing and reporting potential threats, and antivirus software should be configured to automatically scan and update.

CompTIA Network+ Full Course covers network security

Network security includes topics such as network mitigation, threat mitigation, and security policies

Wireless network security is crucial and can be achieved through protocols like WPA and WPA2

High availability refers to the continuous availability of a service for a higher period than normal, achieved through redundant components and protocols like VRRP and HSRP.

Load balancing is the distribution of work across multiple resources, such as servers and networks, to optimize resource usage and enhance throughput.

SNMP (Simple Network Management Protocol) is an application layer protocol used to monitor and manage devices on a network, exchanging management data between managed devices and a network management station.

SNMP consists of a managed device, an SNMP agent running on the device, and an SNMP manager running on a computer that receives and reports information from the agent.

SNMP traps are events reported by an SNMP agent to the SNMP manager, which can trigger actions such as sending emails, SMS alerts, or performing certain tasks.

💡 SNMP, syslog, and SIEM are used for network monitoring and security management.

🌐 Web services allow for data exchange between web-based applications over an IP network.

🖥️ Virtualization allows a single physical computer to operate as multiple virtual machines.

💽 Storage Area Networks (SANs) provide high-speed data transfer and centralized storage.

☁️ Cloud computing enables convenient access to shared computing resources over a network.

🔑 Cloud computing has five characteristics: on demand self-service, broad network access, resource pooling, rapid elasticity, and measured service.

🌐 Cloud service providers offer three service models: software as a service (SaaS), platform as a service (PaaS), and infrastructure as a service (IaaS).

🔒 Physical security controls in data centers include man traps, network closets, video monitoring, door access controls, and fire suppression systems.

💡 Computer forensics involves the collection, examination, analysis, and reporting of digital evidence for use in legal proceedings.

🔌 Data centers require safety practices such as HVAC systems, proper rack loading, fire suppression measures, lift techniques, and anti-static precautions.

⚠️ Material Safety Data Sheets (MSDS) provide information on hazardous chemicals to ensure the safety of workers.

📝 Change management is the process of planning and controlling changes to IT services in order to reduce risk and disruption to the business.

🔄 Types of changes include additions, removals, modifications, and configurations that could impact IT services.

📄 Documentation and standard procedures are key aspects of change management to ensure consistent and efficient handling of changes.

⏰ Maintenance windows are designated time periods when changes can be made with minimal impact on the business.

⚙️ Rollback procedures are put in place to revert changes if they have adverse effects on IT services.

🚨 Notification is an important part of change management to inform stakeholders about upcoming changes and potential impact.

🔑 Understanding how IT works within a business is crucial.

📚 Change management is essential for controlling and implementing changes.

📝 Documentation and communication play important roles in change management.