Switched Ethernet

Send data between microcontrollers and small peripherals

Quick Explanation

  • Supports point to point management
  • Supports troubleshooting
  • Supports fragmentation of incoming packets into frames based on the byte specification
  • Supports full duplex and half duplex

Protocol

  • IEEE 802.3 Layers 2-7

Overview

VisualSim FlexRay Modeling library enables designers to model the FlexRay protocol accurately and to conduct network design trade-offs. It also enables a system designer to construct models of complex standard and non-standard FlexRay topologies.The FlexRay Bus Model is based on the FlexRay ProtocolSpecification V2.1 (2005).

Parameters Used

Systems communicating over VisualSim Ethernet divide a stream of data into shorter pieces called frames. Each frame contains source and destination addresses and error-checking data so that damaged data can be detected and re-transmitted. As per the OSI model VisualSim Ethernet models the services up to and including the data link layer. VisualSim Ethernet can be integrated with other protocols to assemble a full system.

Some of the blocks used in this library are as follows:

  • Station: This block is used for providing traffic
  • ETH_SW: This block acts as a switch

Features

Ethernet stations communicate by sending each other data packets: blocks of data individually sent and delivered. Each Ethernet station is given a MAC address that is used to specify both the destination and the source of each data packet. Ethernet establishes link level connections, which can be defined using both the destination and source addresses. On reception of a transmission, the receiver uses the destination address to determine whether the transmission is relevant to the station or should be ignored. It is possible to intermix multiple protocols on the same physical network and allow a single computer to use multiple protocols together. Since all communications happen on the same wire, any information sent by one computer is received by all, even if that information is intended for just one destination. The network interface card interrupts the CPU only when applicable packets are received: The card ignores information not addressed to it. Use of a single cable also means that the bandwidth is shared, such that, for example, available bandwidth to each device is halved when two stations are simultaneously active.

Some of the key features of this model are as follows:

  • Auto-negotiation
  • Auto MDIX

In General

Switched Ethernet is identical to traditional Ethernet except that a switch replaces the hub. In traditional shared Ethernet, all devices share the same multipoint circuit and must take turns using it. When a frame is sent from one computer to another, it enters the hub and the hub retransmits it to all the computers attached to the hub. With Switched Ethernet, the hub is replaced by a switch. This type of switch is often called a workgroup switch because it is designed to support a small set of computers in one LAN. From the outside, the switch looks almost identical to a hub, but inside, it is very different. A switch is an intelligent device with a small computer built-in that is designed to manage a set of separate point-to-point circuits. That means that each circuit connected to a switch is not shared with any other devices; only the switch and the attached computer use it. The physical topology looks essentially the same as Ethernet’s physical topology; a star. On the inside, the logical topology is a set of separate point-to-point circuits, also a star.

Gigabit- Implements Gigabit Ethernet switch