文档介绍：帧中继 Frame Relay
深圳职业技术学院计算机系网络专业
教学目标( Objectives )
1. 帧中继概念(Frame Relay Concept )
( Frame Relay Terminology )
(Frame Relay Address Mapping)
( LMI Operation)
( Frame Relay Inverse ARP )
6. 配置基本的帧中继( Configuring Basic Frame Relay )
( Configuring Frame Relay Subinterfaces )
帧中继预览 (Frame Relay Overview)
帧中继用虚电路为面向连接的服务建立连接
Virtual circuits make connections for Connection-oriented service
帧中继工作在这里
Frame Relay works here.
DCE or Frame Relay Switch
CSU/DSU
帧中继协议族(Frame Relay Stack)
OSI Reference Model
Frame Relay
Physical
Presentation
Session
Transport
Network
Data Link
Application
EIA/TIA-232, EIA/TIA-449, , , EIA/TIA-530
Frame Relay
IP/IPX/AppleTalk, etc.
帧中继工作在OSI参考模型的物理层和数据链路层
Frame Relay operate physical and datalink layer.
帧中继术语(Frame Relay Terminology)
Local Access Loop=T1
Local Access Loop=64 kbps
Local Access Loop=64 kbps
DLCI: 400
PVC
DLCI: 500
LMI 100=Active 400=Active
DLCI: 200
DLCI: 100
PVC
帧中继术语(Frame Relay Terminology)
(Access rate ):连接本地环到帧中继的端口速度。
The clock speed (port speed) of the connection (local loop) to the Frame Relay cloud.
(DLCI):在源和目的设备之间标识逻辑电路的一个数值。
A number that identifies the end point in a Frame work.
(LMI);是客户前端设备和帧中继交换机之间的信令标准,负责管理设备之间的连接、维护设备之间的连接状态。
A signaling standard between the customer premises equipment (CPE) device and the Frame Relay switch that is responsible for managing the connection and maintaining status between the devices
(CIR):ISP提供的有保障的速率。
The guaranteed rate, in bits per second, which the service mits to providing.
帧中继术语(Frame Relay Terminology)
():当网络发生拥塞的时候,数据包,来通知拥塞。
A bit set in a frame that notifies a DTE that congestion avoidance procedures should be initiated by the sending device
():当网络发生拥塞的时候,数据包,来通知拥塞。同时按25%的比例降低数据报发送速率。
A bit set in a frame that notifies a DTE that congestion avoidance procedures should be initiated by the sending device. If the router receives any