Queues

Queues can be aliased to forwarding classes. A chassis has a max of 16 forwarding classes but only eight queues. If 16 forwarding classes are in use they must be mapped into 8 queues.

forwarding-classes {

class best-effort queue-num 0 priority low;

class ws-bronze queue-num 1 priority low;

class bronze queue-num 2 priority low;

class ws-silver queue-num 3 priority low;

class silver queue-num 4 priority low;

class ws-gold queue-num 5 priority low;

class gold queue-num 6 priority high;

class network-control queue-num 7 priority high;

}

Forwarding classes are given a priority, and a queue number. The priority of any given queue influences the chances whether a packet will be dropped as the result of a RED drop. As RED is not currently used at Blink this parameter has been put in place to allow for future planned features.

The above specifies a set of standard queues to be deployed on all core routers. Three levels of priority are configured, bronze, silver, and gold. A wholesale class is also created for each priority level, mapped to a lower queue. Wholesale traffic, should get the priority guarantees they pay for, however no other carrier should preempt Blink customer traffic of an equal level.

Schedulers

Schedulers are used to specify a transmission rate, and implement RED through the use of drop-profiles. They are also used to specify the loss packet loss priority of any given forwarding class.

schedulers {

CRB1000-VOICE-SCHED {

transmit-rate 256k;

priority high;

}

CRB1000-MAN-SCHED {

transmit-rate 64k;

priority medium-high;

}

CRB1000-NORM-SCHED {

transmit-rate remainder;

priority medium-low;

}...

... middle of paper ...

... loss-priority medium-low code-points 011;

}

forwarding-class gold {

loss-priority low code-points 100;

}

forwarding-class platinum {

loss-priority low code-points 101;

}

forwarding-class network-control {

loss-priority low code-points [ 110 111 ];

}

}

Explicit Null When Using MPLS EXP Bits

By default Junos uses implicit nulls, label 3, to enabled PHP. In order for the QoS bits to be preserved all the way to the egress PE explicit nulls must be sent.

[edit protocols mpls]

# set explicit-null

Troubleshooting

Example Customer

Items Which Require Testing

Verification of transmit rates, exact rates and remainders. What is the behavior of those functions on the MX platform (do they work, unlike the J boxes)? What about shaping (low priority).

Explicit null now required for core right???