Cisco 10000 Series User Manual

5-5
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 5 Distributing Bandwidth Between Queues
Bandwidth Distribution Between Queues
Table 5-2 describes the data included and excluded in the committed rate when a traffic shaper and
policer are configured on the interface.
Table 5-3 describes what bandwidth is based on for each media type.
Bandwidth Allocation to PVCs
The router allocates bandwidth to variable bit rate (VBR), constant bit rate (CBR), and shaped (specifies
the peak cell rate) unspecified bit rate (UBR) PVCs before allocating bandwidth to unshaped UBR
PVCs. As a result, a diminished amount of bandwidth is available to allocate to unshaped UBR PVCs.
To override this behavior, create a hierarchical (nested) policy with the bandwidth specified and attach
the policy to the ATM port or physical interface.
Ta b l e 5-2 Committed Rate Data for Policing and Shaping
Action Frame Relay Ethernet ATM ADSL SDSL
Policing No bit or byte
stuffing
No 7E flags
1
No Frame Check
Sequence (FCS)
1. The router does not account for flags or Frame Check Sequence (FCS) that the hardware adds or removes.
Generic Traffic Shaping
Class-Based Shaping
No Inter-Frame Gap
(IFG)
No Preamble
No Start of Frame
Delimiter (SFD)
No Frame Check
Sequence (FCS)
No cell header
No AAL Common
Part Convergence
Sublayer (CPCS) pad
No ATM trailer
Class-Based Shaping
No ATM cell
overhead
No AAL Common
Part Convergence
Sublayer (CPCS) pad
No ATM trailer
Class-Based Shaping
No ATM cell
overhead
No AAL Common
Part Convergence
Sublayer (CPCS) pad
No ATM trailer
Shaping 4 bytes of Frame
Check Sequence
(FCS)
No bit or byte
stuffing
No 7E flags
Generic Traffic Shaping
Class-Based Shaping
No Inter-Frame Gap
(IFG)
No Preamble
No Start of Frame
Delimiter (SFD)
Frame Check
Sequence (FCS)
ATM cell header
AAL Common Part
Convergence
Sublayer (CPCS) pad
ATM t r a i le r
Class-Based Shaping
No ATM cell
overhead
No AAL Common
Part Convergence
Sublayer (CPCS) pad
Class-Based Shaping
No ATM cell
overhead
No AAL Common
Part Convergence
Sublayer (CPCS) pad
Ta b l e 5-3 Basis for Bandwidth
Media Bandwidth Based On
Frame Relay Fragments
1
1. For Frame Relay networks with link fragmentation and interleaving (LFI) enabled.
Ethernet Bits
ATM variable bit rate (VBR) Sustained cell rate (SCR)
ATM unspecified bit rate (UBR) Peak cell rate (PCR)
ATM constant bit rate (CBR) Peak cell rate (PCR)

Cisco 10000 Series Specifications

General

Brand	Cisco
Model	10000 Series
Category	Network Router
Language	English