ZyXEL Communications XGS3600 Series Manual page 141

Parameter description:
Fast start repeat count
Rapid startup and Emergency Call Service Location Identification Discovery of endpoints is a
critically important aspect of VoIP systems in general. In addition, it is best to advertise only
those pieces of information which are specifically relevant to particular endpoint types (for
example only advertise the voice network policy to permitted voice-capable devices), both in
order to conserve 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 neighbour has been detected in
order share LLDP-MED information as fast as possible to new neighbours.
Because there is a risk of an LLDP frame being lost during transmission between neighbours,
it is recommended to repeat the fast start transmission multiple times to increase the
possibility of the neighbours receiving the LLDP frame. With Fast start repeat count it is
possible to specify the number of times the fast start transmission would be repeated. The
recommended value is 4 times, given that 4 LLDP frames with a 1 second interval will be
transmitted, when an 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 Network
Connectivity Devices, or other types of links.
Coordinates Location
Latitude :

Latitude SHOULD be 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 :

Longitude SHOULD be 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 :

Altitude SHOULD be 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.
Map Datum :

XGS3600 Series User's Guide
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