max-reserved-bandwidth

To change the percent of interface bandwidth allocated for Resource Reservation Protocol (RSVP), class-based weighted fair queueing (CBWFQ), low latency queueing (LLQ), IP RTP Priority, Frame Relay IP RTP Priority, Frame Relay PVC Interface Priority Queueing (PIPQ), or hierarchical queueing framework (HQF), use the max-reserved bandwidth command in interface configuration mode.


http://www.cisco.com/en/US/docs/ios/qos/command/reference/qos_m1.html#wp1054626

Frame Relay RTP Priority

map-class frame-relay <NAME>
frame-relay ip rtp priority <LOW PORT NUMBER> <PORT RANGE> <BANDWIDTH>

Don't forget to configure frame-relay fragmentation (FRF.12) as RTP Priority doesn't work without frame-relay fragmentation.
map-class frame-relay <NAME>
frame-relay fragmentation <SIZE>

Frame Relay Traffic Shape

R1(config)# map-class <CLASS-NAME>
R1(config-map-class)#frame-relay cir <CIR>
R1(config-map-class)#frame-relay bc <CIR>
R1(config-map-class)#frame-relay be <CIR>
R1(config-if)# frame-relay traffic-shaping

Apply to PVC:
R1(config-if)# frame-relay interface-dlc <PVC>
R1(config-fr-dlci)#class <CLASS-NAME>

Apply to interface:
R1(config-if)# frame-relay class <CLASS-NAME>


CIR=Bc/Tc

Be=(AR-CIR)*Tc

AR= Available Rate, the actual physical interface speed.


Don't forget to enable traffic shaping on interface first

R1(config-if)# frame-relay traffic-shaping





http://www.ine.com/resources/01700368.htm

Serial Link Compression

PPP Predictor:
Less CPU, more memory, less efficient.
R1(config-if)# compress predictor

HDLC Stacker (LZ):
More CPU, less memory, more efficient.
R1(config-if)# compress stacker

Frame Relay FRF.9 Compression
R1(config-if)# frame-relay map ip <IP-ADDRESS> <PVC> broadcast IETF payload-compression FRF9 stac one-way-negotiation

Selective Packet Discard

It applies a form of random packet drop to interface FIFO input queue.
It's a hidden command from IOS parser.

ip spd enable

ip spd mode aggressive --> bad packets are dropped as soon as the minimum threshold for hold-queue
is reached

spd headroom <x> --> BGP, IGP, L2 Keepalives

spd extended-headroom <x> --> IGP, L2 Keepalives

ip spd queue max-threshold <x>

ip spd queue min-threshold <x>

show ip spd

http://www.cisco.com/en/US/products/hw/routers/ps167/products_tech_note09186a008012fb87.shtml

Comparing the bandwidth and priority Commands of a QoS Service Policy

http://www.cisco.com/en/US/tech/tk543/tk757/technologies_tech_note09186a0080103eae.shtml

RSVP Maximum Reservable Bandwidth

By default %75 of the bandwidth available on the interface is reservable for RSVP.
To change that max-reserved bandwidth command can be used.

QoS Requirements of Data

• Best-effort data
• DSCP 0
• adequate bandwidth, reserve at least %25 of bandwidth
• Bulk data: 
• DSCP AF11; excess AF12 or AF13
• moderate bandwidth guarantee but constrained
• Transactional / Interactive data:
• DSCP AF21; excess AF22 or AF23
• adequate bandwidth
• Locally defined mission-critical data:
• AF31; excess AF32 or AF33
• adequate bandwidth

End -to-End QoS Network Design - Chapter 2

NBAR Restrictions

NBAR doesn't support the following:

• Non-IP traffic
• Multicast and other non-CEF switching modes
• Asymmetric flows with stateful protocols
• Packets that are originated from or that are destined to the router running NBAR
• Pipelined persistent HTTP requests.
• URL/host/MIME classification with secure HTTP.
• MPLS labelled packets.
• Fragmented packets
• following interfaces:
• Fast EtherChannel
• Interfaces where tunnelling or encryption is used
• ...

http://www.cisco.com/en/US/docs/ios/12_4t/qos/configuration/guide/qsnbar1.html#wp1050835

IPv6 and IPv4 QoS Differences

Differences:

• There is no equivalent for match ip rtp in IPv6
• IPv6 access lists cannot be numbered