Sesión 1

Introduction to Networking

Overview of Learning Objectives

• The module covers seven essential topics, focusing on three main groups: types of networks, topologies, and physical media for data transmission.

• Key concepts include network performance metrics such as bandwidth and latency, along with reference models like TCP/IP and OSI.

Engagement with Participants

• Viewers are encouraged to subscribe to the YouTube channel for updates on future sessions and to use the MUC platform for questions. Prompt and specific inquiries are preferred to avoid overwhelming responses.

Types of Networks

Classification of Networks

• Networks can be categorized based on technology into two primary types: Local Area Network (LAN) and Wide Area Network (WAN). Other classifications exist but are less relevant in this context.

Characteristics of LAN

• LAN connects devices within a small geographical area (100m - 3km), typically owned by an organization that manages its infrastructure. High-speed connections (up to 10 Gbps) are common, with low latency facilitating near-instant communication between devices. Implementation costs are relatively low compared to WAN setups.

Characteristics of WAN

• WAN spans larger distances, connecting multiple LANs across cities or even continents using public or private access routes provided by ISPs. Transmission speeds vary significantly, often relying on fiber optics due to higher costs associated with infrastructure setup compared to LAN systems. Latency is generally higher due to longer distances involved in data transmission.

Network Topologies

Types of Topologies

• Two main categories exist: logical topologies (how data flows) and physical topologies (physical layout). Common types include bus, ring, star, mesh, and hybrid topologies. Each has unique characteristics affecting performance and reliability.

Bus Topology

• Historically popular in the 1980s; it involves connecting all devices via a single cable where failure at any point can disrupt the entire network's functionality—now considered obsolete due to limitations in data transmission efficiency.

Star Topology

• Currently dominant; features a central switch that connects all nodes directly so that failure in one connection does not affect others—providing better fault tolerance than bus topology while maintaining high performance levels through centralized management.

Ring Topology

• Utilizes token passing for data transfer among connected nodes arranged in a circular format; historically used by IBM but now largely replaced by more efficient designs like star topology due to complexity issues related to node failures impacting overall connectivity.

Mesh Topology

• Offers high redundancy through multiple interconnections between nodes; however, implementation is costly and complex due to extensive cabling requirements—initially utilized for military communications ensuring operational continuity during crises like warfare scenarios.

Transmission Media

Wired vs Wireless Transmission Media

• Transmission media is divided into wired (copper cables like UTP) and wireless options; each has distinct advantages depending on application needs such as distance coverage or speed requirements.

UTP Cable Characteristics

• UTP cables are widely used for networking due to their cost-effectiveness but have limitations regarding maximum length without repeaters (~100m). They can suffer from electromagnetic interference if not properly shielded or installed correctly within designated environments like ducts designed for minimizing signal loss risks during installation processes.

Fiber Optic Cables

• Fiber optic technology allows long-distance communication via light pulses; it comes in two forms: single-mode (for longer distances) and multi-mode (for shorter distances but better sensitivity)—critical considerations when selecting appropriate cabling solutions based on specific networking needs or environmental factors influencing deployment strategies.

Understanding UTP and Fiber Optic Cables

Transmission Mechanisms

• UTP cables transmit electromagnetic pulses, allowing electrons to flow freely through the cable.

• In contrast, fiber optic cables function like tunnels that transmit light pulses through a thin glass filament.

Speed of Light and Internal Reflection

• The phenomenon of internal reflection in fiber optics causes light to bounce within the core until it reaches its destination, enabling rapid transmission.

• Despite this speed, losses occur due to reflections and curvature in the fiber, resulting in speeds slightly less than 300,000 km/s.

Types of Fiber Optics

• There are two main types of fiber: single-mode (monomodo) and multi-mode (multimodo), with standards such as OM3, OM4, and OM5 for multimode fibers.

• Each type serves different purposes; for instance, OM3 is used for campus connections while OM4 is suitable for data centers.

Performance Characteristics of Fiber Optics

Speed and Distance Limitations

• Single-mode fibers can theoretically achieve speeds above 100 GB/s but actual performance depends on physical configurations.

• Multi-mode fibers have varying speeds from 1 GB/s to 10 GB/s depending on their type; distances range from 300m to over 400m based on the specific standard used.

Trade-offs Between Speed and Distance

• Higher speeds may require shorter distances; conversely, longer distances necessitate lower speeds due to signal degradation.

Advantages of Fiber Optics

Immunity to Interference

• Fiber optics are largely immune to electromagnetic interference when properly protected, making them ideal for industrial environments.

Cable Configurations

• Fibers can come in various configurations ranging from a few pairs up to more than 40 pairs within a single cable.

Wireless Communication Overview

Data Transmission via Electromagnetic Waves

• Wireless communication transmits data using electromagnetic waves through air rather than physical cables.

Factors Affecting Wireless Communication

• Key factors include propagation distance and speed; understanding these helps determine appropriate wireless technologies for specific applications.

Wi-Fi Standards Explained

Wi-Fi Technology Basics

• Wi-Fi operates under specific standards (802.11 variants), ensuring compatibility among devices certified by the Wi-Fi consortium.

Mobility Benefits

• The primary advantage of wireless networks is mobility; users can connect without complex installations or cabling constraints.

Managing Wireless Networks

Channel Management

• Wireless networks avoid collisions by utilizing distinct channels within the same frequency spectrum. Proper channel separation enhances network performance.

Automatic Configuration

• Most modern devices auto-configure channels but manual adjustments can optimize performance based on user needs or environmental conditions.

Bandwidth Comparisons

Frequency Bands

• 2.4 GHz: Up to 600 Mbit/s.

• 5 GHz: Up to 3.5 Gbit/s.

• 6 GHz: Up to 9 Gbit/s if supported by devices.

Connection Quality Considerations

• Device proximity affects connection quality; greater distance typically results in reduced speed and reliability.

Comparing Wired vs Wireless Networks

Network Performance Metrics

• Comparison between wired (e.g., UTP Cat6 & optical fibers )and wireless networks highlights differences in speed capabilities ranging from 1GBps up to nearly 10GBps with Wi-Fi technology.

Key Networking Concepts

Understanding Bandwidth vs Latency

• Bandwidth refers to data transmission capacity over time; higher bandwidth allows more data transfer simultaneously.

Latency Defined

• Latency measures delay in data travel time between source and destination, impacting real-time applications like video calls or gaming significantly.

Throughput vs Jitter Explained

Throughput Measurement

• Throughput indicates effective data transfer rates during communication sessions compared against theoretical maximum bandwidth limits.

Jitter Impact on Communication Quality

• Variability in packet arrival times leads to jitter which negatively affects voice/data transmissions causing interruptions or delays during conversations or streaming activities.

Problemas de Ancho de Banda y Latencia

Congestión en la Conexión

• En una descarga de 60 Mbit/s sobre un enlace de 100 Mbit/s, se experimenta congestión y sobrecarga, lo que impide alcanzar la velocidad máxima.

• La alta latencia o el jitter pueden causar cortes en videollamadas, a pesar de que la conexión a Internet funcione correctamente.

Diferencias entre Modelos OSI y TCP/IP

• Se presenta una comparación entre el modelo OSI, un modelo educativo no funcional, y el modelo TCP/IP, que es más práctico.

• El modelo OSI ayuda a entender cómo los datos viajan desde aplicaciones hasta medios físicos a través de sus siete capas.

Estructura del Modelo OSI

Capas del Modelo OSI

• Las capas del modelo OSI incluyen: aplicación, presentación, sesión, transporte, red, enlace de datos y física; cada una tiene funciones específicas en la transmisión de datos.

• La capa de presentación se encarga del formato y compresión de los datos; mientras que la capa de sesión gestiona las conexiones entre aplicaciones.

Importancia de la Capa de Transporte

• La capa de transporte es crucial para determinar cómo se segmentan los datos durante su viaje. También maneja el direccionamiento necesario para su envío.

Detalles Técnicos del Modelo OSI

Transmisión en Capas

• En la capa de red se ejecuta la transmisión real; aquí se establecen parámetros específicos para el envío.

• La capa de enlace define direcciones MAC y está dividida en control lógico y acceso al medio.

Medios Físicos

• La capa física abarca diferentes tipos como cables coaxiales o fibra óptica; cada uno transporta bits mediante distintos métodos físicos.

Protocolo Data Units (PDU)

Concepto PDU

• Los elementos que componen una PDU son: datos, segmentos, paquetes, tramas y bits. Cada uno representa el mismo dato pero encapsulado diferente según su posición en las capas.

Comparación entre Modelos TCP/IP y OSI

Estructura Monolítica del TCP/IP

• A diferencia del modelo OSI, TCP/IP es monolítico con niveles definidos pero sin separación clara entre ellos.

• Las capas superiores (aplicación/presentación/sesión), así como las inferiores (transporte/red/enlace físico), están agrupadas bajo menos categorías.

Preguntas Frecuentes sobre Redes

Ejemplos Prácticos

• Un ejemplo clásico mencionado es una red híbrida donde múltiples dispositivos están conectados a un switch configurado adecuadamente para optimizar conexiones.

Análisis del Ancho de Banda vs. Throughput

• El throughput suele ser menor que el ancho de banda debido al uso adicional por encabezados protocolarios y retransmisiones necesarias durante la comunicación.

Latencia en Juegos Online

Impacto en Experiencias Gaming

• En videojuegos online, aunque un jugador tenga alto ancho de banda (200 Mbit/s), puede experimentar lag debido a latencia elevada o jitter excesivo.

Recomendaciones para Conexiones Largas

Uso Adecuado de Fibra Óptica

• Para distancias mayores a 100 m entre edificios separados (800 m), se recomienda utilizar fibra óptica para asegurar calidad en la conexión.

Normativas RJ45

Estándares para Cableado

Las normas TIA/EIA 568A/B regulan cómo deben ser cableados los conectores RJ45 para minimizar interferencias como diafonía mediante trenzado adecuado.

Elección entre Fibra Monomodo vs. Multimodo

Aplicaciones Específicas

• Se prefiere fibra monomodo para enlaces largos interurbanos mientras que multimodo es ideal dentro campus o industrias locales según normativas TIA/EIA 569.

Resumen Final

Temas Abordados

• Se revisaron temas clave como redes LAN/WAN con sus topologías correspondientes; además se discutieron medios adecuados para transmisión efectiva minimizando problemas comunes como latencia o jitter.