User's Guide

Table Of Contents
3 Product Features
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3 Product Features
This section provides descriptions of the main features of PTP 500 product architecture.
The following topics are described in this section:
3.1 Ethernet Frames
3.2 Management Function
3.3 Configuration and Management
3.4 Channel Bandwidth and Link Symmetry Control
3.5 Non Line Of Sight (NLOS) and Line Of Sight (LOS)
3.6 Upgradeable Software
3.7 Networking Information
3.8 Link Mode Optimization
3.9 Telecoms Circuits
3.10 Radar Avoidance
3.1 Ethernet Frames
The PTP 500 series provides wireless Ethernet bridging between two fixed locations. To be
more precise, it forwards Ethernet frames as a two-port transparent heterogeneous
encapsulation bridge, meaning that each bridge forwards frames between two dissimilar
interfaces (Ethernet and wireless), encapsulating Ethernet MAC frames within a PTP MAC
frames for transmission at the wireless interface. A link consisting of a pair of back to back
bridges appears to the data network to be very similar to a standard two-port Ethernet bridge.
The PTP 500 series provides eight traffic classes, classifying Ethernet frames into one of
eight prioritized queues based on inspection of the user priority field (802.1p) in a customer
(IEEE802.1Q) VLAN tag or provider (IEEE802.1ad) VLAN tag. Untagged frames receive a
default priority. The scheduling method is strict priority. The bridge does not implement any
VLAN functions for bridged frames apart from inspection of the priority field, and consequently
the bridge forwards tagged and untagged Ethernet frames regardless of VLAN ID and without
modification of any protocol header field.
The PTP 500 series supports a maximum Ethernet frame size of 2000 bytes for bridged
traffic.