Basic Concepts andWired Ethernet LANs

Figure 9-2A client-server modelwith a general server

Figure 9-1A client-server model with dedicated servers

Serverske uloge

Figure 9-3Peer-to-peer model

Figure 9-4Physical bus topology

Terminirana mreza

Neterminirana mreza

Prekid jednog

Figure 9-5Physical star topology

Zvijezda

The star topology is the dominant physical topology today.Note:

Figure 9-6Logical bus topology

In 1985, the Computer Society of the IEEE developed Project 802. It covers the first two layers of the Internet model.Note:

Figure 9-7Logical star topology

Technical Focus: Ring Topology

Another physical topology common at the beginning of the LAN era was the ring topology. In a ring topology, each station isconnected to the next station as shown in the following figure:

Project 802 has split the data link layer into two different sublayers: logical link control (LLC) and media access control (MAC). Note:

Figure 9-8LAN compared with the Internet model

Figure 9-9Collision in CSMA/CD

Kolizija

Technical Focus: Ethernet Addressing

Each station on an Ethernet network (such as a PC, workstation, or printer) has its own network interface card (NIC). The NIC usually fits inside the station and provides the station with a 6-byte (48-bit) physical address.

Figure 9-10Implementations of Ethernet

Figure 9-11:aEthernet connection to the medium

Figure 9-11:bEthernet connection to the medium

Figure 9-11:cEthernet connection to the medium

Figure 9-11:dEthernet connection to the medium

Technical Focus: Ethernet Frame

Traditional Ethernet has a frame with the following format:

Figure 9-12Switched Ethernet

Figure 9-13Fast Ethernet implementations

Figure 9-14:aFast Ethernet connection to the medium

Figure 9-14:bFast Ethernet connection to the medium

Figure 9-14:cFast Ethernet connection to the medium

Figure 9-15Gigabit Ethernet implementations

Figure 9-16:aGigabit Ethernet connection to the medium

Figure 9-16:bGigabit Ethernet connection to the medium

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