Altice Labs FGW GR140DG Wi-Fi 6, Руководство пользователя

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FiberGateway
Figure 9: Dowstream QoS diagram
In the downstream direction, Figure 9, the ingress traffic can be firstly classified. It passes by a policer
and is configured to each ONT service, which is defined by one or two tags. It is remarked and policed
per-CoS rate (port profile).
After this, Network services (per VLAN) classification determine the PON port queue where packets will
wait for a transmission opportunity, and can remark the CoS (P-bits in VLAN PCP). The traffic is put in
a queue according with the p-bit/DSCP->Traffic Class mapping.
Each of these Traffic Classes is associated with a scheduler (WRR or SP) and a policer.
Queue congestion management is used to prevent the queue from overflowing and is performed based
on Tail Drop or WRED.
Each queue is served by either a priority or weighted scheduler and rate controlled.
Then Traffic Classes to P-bit remarking is done and the traffic flows to the GPON interface.
Destination ONU/ONT client service downstream profile defines traffic classless policing. The overall
PON port may be limited to a percentage of its capacity.
Traffic arriving to the ONU/ONT it will pass by a mapping block which will map the traffic in one of the
eight queues according with the p-bits; these queues have a Strict Priority scheduler in order to
guarantee that the most prioritized traffic passes first, Figure 10: Upstream QoS diagram
.
2.6.2 Upstream QoS
In the upstream, Figure 11: Traffic distribution by service/client
, for each T-CONT DBA the ingress traffic in the ONT passes by a mapping block that maps the traffic
in one of the eight queues according with the p-bit, (in case the ingress traffic is untagged a DSCP->p-
bit mapping is performed).
These queues have a Strict Priority Scheduler. Packets are stored at the intended T-CONT priority
queue, which is scheduled according to ONT configuration.
The ONT “waits” until the OLT assigns a transmission timeslot for that T-CONT, according to DBA, so
that the most prioritized queues are the ones that transmit first.
In the OLT PON ingress port, traffic is remarked and can be policed per-CoS. The traffic is put into a
Traffic Class according with what is defined in the p-bit/DSCP->queue mapping.