Televes OLT 769401, Руководство пользователя

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2.8.4.5 MAC/IP Spoofing
MAC/IP spoofing is used to allow only the authorized customers to access the network. This mechanism uses the DHCP Binding Table. The table
with the client MAC address/IP address is built during the DHCP client IP attribution. The packet attributes from the client will only pass through
the network in the case they have the same SMAC/SIP like those at the Binding Table.
2.8.4.6 Storm Attack Rate Limiters
The OLT allows the configuration of “Storm Attack” rate limiters in order to prevent malicious users that try to stress the network and the CPU of
the network elements causing DoS on the system.
There are three types of configurable rate limiters:
Broadcast
Multicast
Unicast Unknown
Rate limiters parameter Maximum rate in bps (bits per second) is configurable between 0 and 1Mbps. Default configured value is of 1M bps
These limiters are applied to all services except:*
In-band traffic
Bitstream services
Multicast services (CPU trap active but MC flood is off)
2.8.4.7 User Isolation
User isolation is achieved by the topology of the EVC’s created in the system. The services are created in an EVP-TREE topology, the Root port is
the uplink port and the Leaf ports are the client ports. Within this implementation, users can’t communicate between themselves and just flow
transparently through the Access Node.
2.8.5 QoS
The OLT system provides several QoS mechanisms, that can be targeted to the flow characterized by one or two VLAN according with the type of
service, or can be targeted to the packets priority, where each p-bit is mapped in one of eight queues of each port.
The following QoS features are supported on each one of the Ethernet OLT ports:
Classification : DSCP to P-bit mapping
Queuing,
Scheduling
Rate Limiting (Ethernet Profiles’ configurable parameters: CIR, CBS, EIR, EBS)
Forward PON traffic based on P-bits
For each of the OLT ports there are associated eight queues; for each of these queues is possible to configure the p-bit mapping in one of the
queues, the scheduler type (Strict Priority or Weighted Fair Queuing) and the minimum and maximum bandwidth of each queue.
In the downstream direction the ingress traffic first passes by a policer configured to each ONT service, which is defined by one or two tags. After
this the traffic is put in a queue according with the p-bit ->queue mapping. Each of these queues is associated with a scheduler and a policer. Then
the traffic flows to the GPON interface and when it arrives to the 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.