Week 3: Identifying Network Topologies and Standards - M199205zn/Datacomm-CS3 GitHub Wiki

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A network topology refers to the arrangement of nodes (devices) and connections in a network. It determines how data flows between devices and influences performance, scalability, and fault tolerance.

1. Physical Topology

   

   • Refers to the physical arrangement of devices and cables.

2. Logical Topology

   

   • Describes the path data takes within the network, independent of its physical layout.

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1. Bus Topology

   • Description: All devices are connected to a single central cable (the bus).
   • Advantages: Simple and cost-effective for small networks.
   • Disadvantages: If the bus fails, the entire network goes down.

2. Star Topology

   • Description: Devices are connected to a central hub or switch.
   • Advantages: Easy to add/remove devices; a single device failure doesn't impact others.
   • Disadvantages: If the central hub fails, the entire network is affected.

3. Ring Topology

   • Description: Devices are connected in a circular pattern, and data travels in one direction.
   • Advantages: Simple data flow with predictable performance.
   • Disadvantages: A single failure can disrupt the entire network.

4. Mesh Topology

   • Description: Every device is connected to every other device.
   • Advantages: High redundancy and fault tolerance.
   • Disadvantages: Expensive and complex to set up for large networks.

5. Hybrid Topology

   • Description: A combination of two or more topologies.
   • Advantages: Flexible and scalable to meet network requirements.
   • Disadvantages: Can be complex to manage.

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Network standards are guidelines for hardware, software, and protocols to ensure interoperability across devices and systems. These standards are established by organizations like IEEE, ISO, and IETF.

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Ethernet is a widely used networking technology for local area networks (LANs). The IEEE 802.3 standard defines Ethernet specifications, including transmission speed, cabling, and media access control.

1. Based on Speed:

   • 10 Mbps (Ethernet):
     • Standard: 10BASE-T
     • Media: Twisted pair cables.
     • Use: Legacy networks.
   • 100 Mbps (Fast Ethernet):
     • Standard: 100BASE-TX
     • Media: Twisted pair cables.
     • Use: Small-scale networks.
   • 1 Gbps (Gigabit Ethernet):
     • Standard: 1000BASE-T
     • Media: Twisted pair or fiber optic cables.
     • Use: Modern LANs requiring high-speed data transmission.
   • 10 Gbps (10-Gigabit Ethernet):
     • Standard: 10GBASE-T
     • Media: Twisted pair or fiber optics.
     • Use: Data centers and high-performance networks.

2. Based on Media Type:

   • Twisted Pair:

     

     • Example: 1000BASE-T.
   • Fiber Optic:

     

     • Example: 10GBASE-SR (short range) and 10GBASE-LR (long range).

3. Based on Distance:

   • Short Range:
     • Example: 10BASE-T (up to 100 meters).
   • Long Range:
     • Example: 10GBASE-LR (up to 10 kilometers).

• CSMA/CD (Carrier Sense Multiple Access with Collision Detection): Used in traditional Ethernet to manage data collisions.
• Full-Duplex: Enables simultaneous sending and receiving of data.
• Backward Compatibility: Ensures newer Ethernet standards can coexist with older ones.

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Standard	Speed	Media	Max Distance	Use Case
10BASE-T	10 Mbps	Twisted pair	100 meters	Legacy systems
100BASE-TX	100 Mbps	Twisted pair	100 meters	Small-scale LANs
1000BASE-T	1 Gbps	Twisted pair	100 meters	Modern office networks
10GBASE-T	10 Gbps	Twisted pair	55-100 meters	High-performance workstations
10GBASE-LR	10 Gbps	Fiber optics	Up to 10 km	Long-distance data center networks

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Understanding network topologies helps in designing efficient and scalable networks, while Ethernet standards ensure seamless communication across devices. Selecting the right topology and standard depends on the network size, performance requirements, and budget.