3Com OfficeConnect Remote 510 User Manual

Contents

Bridging and Routing Concepts A-3local LAN because it does not recognize thedestination station as local. However, if thedestination device is on the local LAN, once it repliesto the original source station, its own source addressis part of the data frame and it is learned by thebridge and added to the address table.By operating in this way, the amount of dataforwarded by the bridge is kept to a minimum.Traffic that is for devices on the attached LAN israrely forwarded over the bridge.A bridge can be configured to forget or age astation’s address after a period of inactivity, a facilitywhich is used to ensure that stations which are nolonger attached to the LAN, do not remain in thebridge’s address table, using up space that may berequired for other stations’ addresses.Some bridges allow address information to bemanually configured into the bridge, provided theautomatic learning facility is turned off, although thiswill not normally prove necessary unless specifictraffic filtering is required.You can also configure a number of other featuresto improve the performance and operation of theOfficeConnect Remote. These include sophisticatedframe filtering techniques so that only certain typesof frame, or those associated with particular workgroups, are passed between specific segments.Bridging Between Remote SitesThe OfficeConnect Remote is able to send framesbetween LANs that may be separated byconsiderable physical distances. It achieves this bymaking use of Wide Area Network (WAN) links. WANscan be established by using either digital leased linesor ISDN and are usually operated by telephonecompanies (PTTs) or other service providers.Figure A-1 shows two LAN segments, A and B, whichare connected by a pair of OfficeConnect Remoteunits, 1 and 2. The type of link between the twodepends on the WAN services available at each ofthe remote bridge locations, and the price thenetwork administrator is willing to pay for thoseservices.Rc.bk : RCAPPA.FRM Page 3 Thursday, July 10, 1997 9:53 AM