Q-Lite Satellite Modem Installation and Operating Handbook
6-59
6.2.3.13 MPE MAC Address
Format
example:
00:11:29:00:F0:23
Description:
For DVB-S2 IP services, this is used for filtering of Multi-Protocol
Encapsulation (MPE) packets on the receive side. The receiver will filter
against whatever MAC address has been provided, which can therefore
be a virtual MAC address rather than the receiver’s address.
(There is currently no equivalent modulator support to allow a specific
MAC address to be added to MPE packets. A Paradise modulator will
always set the MPE MAC address to all zeros or the modulator’s MAC
address, depending on whether it is in routing or bridging mode.)
Table 6-56 MPE MAC Address
6.2.3.14 Weighted QoS
This is an On/Off control that controls IEEE 802.1p packet prioritization. It is mutually
exclusive with the traffic shaping feature and when traffic shaping is enabled then
strict/fair queuing will be automatically switched off.
This allows for eight classes of data to be specified as part of a three-bit field within the
Layer 2 IEEE 802.1q VLAN header. The packets must already be tagged at the point of
entry to the modem. Priority 7 is typically used for network-critical traffic such as dynamic
routing protocol packets; priorities 5 and 6 for video and voice, etc. The modem uses the
priority tag to decide how to process each packet. The options are:
•
Strict-priority queuing
: packets are queued for transmission based solely on
their priority with the highest always being sent first. Strict-priority queuing is
active whenever
Weighted QoS
is set to Off.
•
Fair-weighting queuing
: higher-priority packets are transmitted first but
lower-priority packets are given a percentage of the bandwidth. Fair-weighting
queuing is active whenever
Weighted QoS
is set to On.
The implementation of IEEE 802.1p packet prioritization is as follows:
•
The eight QoS priority levels are mapped to three TCP/IP queues in the
modem.
•
Packets with highest QoS priority (level 7) are sent to high priority TCP/IP
queue.
•
Delay-sensitive packets (QoS levels 6 and 5) are sent to the medium priority
queue.
•
The remainder (QoS levels 4 to 0) are sent to the low priority TCP/IP queue.
•
For strict-priority queuing, all packets in the high-priority queue are processed
before any in the medium-priority queue, which in turn are processed before
any in the low-priority queue.
For fair-weighting queuing, for every four packets sent from the high-priority queue, two
are sent from medium-priority queue and one from the low-priority queue.
