CCNA学习笔记1

1.1  ISO/OSI

1.2  OSI layers and lan specification

1.3  tokenring

1.4  fiber distributed data interface,FDDI

1.5  ethernet

1.6  线缆类型

1.7  cisco 3 layers

1.1  ISO/OSI

参考点，分层原则

physical/ data link/network/transport/session/presentation/application

MAC 802.3,802.5       LLC 802.2

1.2  OSI layers and lan specification

LAN MAC 802.3   100BASET  tokenring  fddi

ethernet and ieee802.3

1.3  tokenring

SOF

1.4  fiber distributed data interface,FDDI

令牌传递+双环结构

1.5  ethernet

CSMA/CD:media contention /collision/(carrier sense multiple access/collision detect)

COLLISION DOMAIN AND BROADCAST DOMAIN segmentation

hub/repeater/switch/bridge/router/VLAN of switch

ethernet 帧格式4

1.6  线缆类型

cut-through/crossover(uplink)/rollover

1.7  cisco 3 layers

core layer:high-speed and reliable switching

distribution layer:policy-based connectivity

access layer:local and remote workgroup access