5-102 41-001343-01 Rev 02, Release 3.2.2Link Layer Discovery Protocol for Media Endpoint Devices ( LLDP-MED) andEmergency Location Identification Number (ELIN)The IP Phones support Link Layer Discovery Protocol for Media Endpoint Devices(LLDP-MED). LLDP-MED is designed to allow for things such as:• Auto-discovery of LAN policies (such as VLAN, Layer 2 Priority and Diffserv settings)leading to "plug and play" networking.• Extended and automated power management of Power over Ethernet endpoints.• Inventory management, allowing network administrators to track their network devices, anddetermine their characteristics (manufacturer, software and hardware versions, serial / assetnumber).On the IP Phones, LLDP-MED performs the following:• Supports the MAC/PHY configuration (e.g. speed rate/duplex mode).• Supports VLAN info from the network policy; this takes precedence over manual settings.• Allows you to enable/disable LLDP-MED if required.• Allows you to configure time interval between successive LLDP Data Unit (LLDPDU)frames.• Allows LLDP packets to be received from the LAN port.• Allows the phone to use the location information, Explicit Congestion Notification (ECN)Emergency Location Identification Number (ELIN), sent by the switch, as a caller ID formaking emergency calls.Previously, Aastra IP Phones had a 5 second time-out for listening to LLDP-MED responseswhen the phone is booting up. If LLDP-MED responses are received after this initial listeningperiod, the phone will ignore the response. Now administrators can configure this time-outinterval using the new "lldp startinterval" parameter. This parameter is only valid during thephone bootup process and it will control the LLDP-MED time-out interval where the phonesends LLDP-MED advertisements and listens for the LLDP-MED responses from the switchbefore proceeding to the DHCP stage. The default value of this parameter is 5 seconds.Note: If the phone receives location information in ECN ELIN format(10 to 25 numeric string), the phone replaces the caller ID SIP headerwith the ECN ELIN value and the SIP URI does not change. The phonedetermines if this is an emergency number by checking the emergencydial plan configured on the phone.
