Cabletron Systems 2200 Installation & User Manual

Contents

Cabletron Systems 2200 Installation & User Manual Manual pdf 23 page image

OverviewIntroduction 1-31.1.3 Standard/Full Duplex Auto-NegotiationPorts 1 through 48 on the 2E253-49R have the ability to auto-negotiate the port mode of operation(standard [half duplex] or full duplex) between two devices according to the 802.3x standard. Fullduplex mode is the default mode of operation for each port. During Auto-Negotiation, two devicesautomatically exchange information “telling” each other their current operating mode. TheAuto-Negotiation feature targets the maximum capability that can be reached between the twodevices. For example, the 2E253-49R can adjust to full duplex operation when the device on theother end of the connection can also adjust from standard to full duplex. If the device on the otherend of the connection can only operate in standard mode, then the 2E253-49R simply adjusts tooperate to the standard mode.1.1.4 Runtime IP Address DiscoveryThis feature enables the 2E253-49R device to automatically accept an IP address from a BootStrap Protocol (BootP) server on the network into NVRAM without requiring a user to enter an IPaddress through Local Management.When the device is connected to the network and powered up, Runtime IP Address Discovery(RAD) checks the device for an IP address. If one has not yet been assigned (device IP address setto 0.0.0.0), RAD checks to see if any of the device interfaces have a link. If so, RAD sends outReverse Address Resolution Protocol (RARP) and BootP requests to obtain an IP address from aBootP server on the network.The RAD requests start at an interval of 1 per second. The interval then doubles after everytransmission until an interval of 300 seconds is reached. At this point, the interval remains at 300seconds. The RAD requests continue until an IP address is received from an RARP or BootPserver, or an IP address is entered using Local Management.1.1.5 SmartTrunkTraditional 802.1D Spanning Tree Bridges only allow one active data path between any twoswitches; all other parallel data paths are in Standby or Blocking mode. If one interface or pathshould fail, then the other interface automatically comes out of Blocking mode and forwards all ofthe traffic. This is fine for redundancy purposes. However, it is not the most efficient use ofresources.NOTEThe 2E253-49R will reboot after RAD is successful.