1 / 10

One Upon A Time Computer Networks

One Upon A Time Computer Networks . The First Switched Network. Layer-2 Switching. Advantages: Hardware based (Uses the MAC address from the host’s NIC card) Not software devices Fast and efficiency Increases the bandwidth for each user Limitations: Does not break up broadcast domains

fairly
Download Presentation

One Upon A Time Computer Networks

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. One Upon A Time Computer Networks

  2. The First Switched Network

  3. Layer-2 Switching • Advantages: • Hardware based (Uses the MAC address from the host’s NIC card) • Not software devices • Fast and efficiency • Increases the bandwidth for each user • Limitations: • Does not break up broadcast domains • Make sure users spend 80% of time on the local segment

  4. ARP (DNS) 0200.2222.2222 E01 1 DMAC:FFFF.FFFF.FFF SMAC: 0200.222.2222 ARP 0200.2222.2222 E01 0200.1111.1111 E03 2 DMAC:0200.2222.2222 SMAC: 0200.1111.1111 ARP Request 3 DMAC: 0200.1111.1111 SMAC: 0200.2222.2222 ARP 4 DMAC: 0200.2222.2222 SMAC: 0200.1111.1111 ARP (web) 5 DMAC: FFFF.FFFF.FFFF SMAC: 0200.1111.1111 0200.2222.2222 E01 0200.1111.1111 E03 0200.3333.3333 E02 6 DMAC: 0200.1111.1111 SMAC: 0200.3333.3333 Address Learning WWW:0200.3333.3333 PC:0200.2222.2222 DNS:0200.1111.1111 E01 E02 E03

  5. Forward/Filter Decisions • When a frame arrives: • Case 1: DMAC is known and in the database • Case 2: DMAC is not listed • Case 3: It is a broadcast

  6. Loop Avoidance • Redundant links are use between switches/bridges to increase survivability • Disadvantages: • Broadcast storms • Trashing the MAC table

  7. Spanning Tree Protocol (STP) • STP is used to avoid networks loops on layer-2 networks (bridges and switches) • STP is a bridge protocol that make sure that transmission takes place over a spanning tree topology • Spanning tree terms: • Root Bridge: • the bridge with the best bridge ID • all decision in the network are made on this bridge • Bridge ID: • lowest bridge ID becomes the root bridge

  8. Nonroot Bridge • Bridge Protocol Data Unit (BPDU) • Root Port • The link directly connected to the root bridge, or the shortest path to the root bridge • Designated/Nondesignated port • Port cost • Forwarding port • send and receives all data • Blocked port • does not participate in frame forwarding

  9. Spanning-Tree Operations • Selecting the root bridge • Selecting the designated port • Port States • Blocking • Listening • Learning • Forwarding • Disabled

  10. Example: Find The Root Bridge and Root Ports

More Related