Cabletron Systems 2H253-25R Installation & User Manual

Contents

Cabletron Systems 2H253-25R Installation & User Manual Manual pdf 23 page image

OverviewIntroduction 1-3When Auto-Negotiation is supported at both ends of a link, the two devices dynamically adjust tofull or half duplex operation based on the maximum capability that can be reached between thetwo devices. If the device connected to the 2H253-25R cannot auto-negotiate, the 2H253-25Roperates according to the capabilities of the other device.1.1.3 Runtime IP Address DiscoveryThis feature enables the 2H253-25R device to automatically accept an IP address from a BootStrap Protocol (BootP) server on the network without requiring a user to enter an IP addressthrough 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 a RARP or BootP server,or an IP address is entered using Local Management.1.1.4 Full Duplex Switched EthernetEach switched Fast Ethernet port on the 2H253-25R supports 10/100 Mbps operation, and canoperate in Full Duplex Switched Ethernet (FDSE) mode. FDSE enables each port to provide up to200 Mbps of bandwidth to connected devices that support FDSE.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 2H253-25R will reboot after RAD is successful.