[tforum] Link Layer Discovery Protocol (LLDP)

Joe Breen Joe.Breen@utah.edu
Thu, 29 Dec 2005 14:13:45 -0700


Many of you have probably traditionally used the Cisco Discovery Protocol (CDP)
to map networks at Layer 2 or to just to find out the neighboring switch or
router.  CDP is a proprietary layer 2 protocol from Cisco and is only partially
supported (or not at all) by other vendors.  The IEEE has now standardized the
802.1AB Link Layer Discovery Protocol (LLDP).  Many vendors are now starting to
support this protocol.  This protocol yields similar info to CDP plus some
additional info.  This protocol, similar to CDP, allows more accurate topology
mapping and even stores this info in RFC 2922 Physical Topology MIB objects.  

For those that monitor/map their networks closely or use link layer protocols as
additional troubleshooting tools, LLDP makes another useful tool.

     --Joe