SMC Networks SMCGS10P-SMART Management Manual page 150

| Configuring the Switch
C 4
HAPTER
Link Layer Discovery Protocol
the limited LLDPU space and to reduce security and system integrity
issues that can come with inappropriate knowledge of the network
policy.
With this in mind LLDP-MED defines an LLDP-MED Fast Start interaction
between the protocol and the application layers on top of the protocol,
in order to achieve these related properties. Initially, a Network
Connectivity Device will only transmit LLDP TLVs in an LLDPDU. Only
after an LLDP-MED Endpoint Device is detected, will an LLDP-MED
capable Network Connectivity Device start to advertise LLDP-MED TLVs
in outgoing LLDPDUs on the associated port. The LLDP-MED application
will temporarily speed up the transmission of the LLDPDU to start
within a second, when a new LLDP-MED neighbor has been detected in
order share LLDP-MED information as fast as possible to new
neighbors.
Because there is a risk that a LLDP frame being lost during transmission
between neighbors, it is recommended to repeat the fast start
transmission multiple times to increase the possibility for that the
neighbors has received the LLDP frame. With Fast start repeat count it
is possible to specify the number of times the fast start transmission is
repeated. The recommended value is 4 times, giving that 4 LLDP
frames with a 1 second interval will be transmitted, when a LLDP frame
with new information is received.
It should be noted that LLDP-MED and the LLDP-MED Fast Start
mechanism is only intended to run on links between LLDP-MED
Network Connectivity Devices and Endpoint Devices, and as such does
not apply to links between LAN infrastructure elements, including
between Network Connectivity Devices, or to other types of links.
Coordinates Location
Latitude – Normalized to within 0-90 degrees with a maximum of 4
◆
digits. It is possible to specify the direction to either North of the
equator or South of the equator.
Longitude – Normalized to within 0-180 degrees with a maximum of 4
◆
digits. It is possible to specify the direction to either East of the prime
meridian or West of the prime meridian.
Altitude – Normalized to within -32767 to 32767 with a maximum of 4
◆
digits. It is possible to select between two altitude types (floors or
meters).
Meters: Representing meters of Altitude defined by the vertical
■
datum specified.
Floors: Representing altitude in a form more relevant in buildings
■
which have different floor-to-floor dimensions. An altitude = 0.0 is
meaningful even outside a building, and represents ground level at
the given latitude and longitude. Inside a building, 0.0 represents
the floor level associated with ground level at the main entrance.
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