Proxim 5012-SUI, Руководство по установке и управлению

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System Overview Tsunami MP.11 5012/5054-SUI Installation and Management
Quality of Service (QoS)
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e. Minimum Reserved Traffic Rate = 2 Mbps
f.
Maximum Latency = 20 milliseconds
g. Traffic Priority = 1
Note that two different VoIP Service Flow classes for each direction of traffic have been defined (index numbers 3 to 6)
which follow the ITU-T standard nomenclatures: G.711 refers to a type of audio companding and encoding that produces
a 64 Kbps bitstream, suitable for all types of audio signals. G.729 is appropriate for voice and VoIP applications, but
cannot transport music or fax tones reliably. This type of companding and encoding produces a bitstream between 6.4
and 11.8 Kbps (typically 8 Kbps) according to the quality of voice transport that is desired.
QoS Class
A QoS class is defined by a set of parameters that includes the PIRs and SFCs that were previously configured. The
software allows creating up to eight different QoS classes, including four predefined QoS classes. Up to four SF classes
can be associated to each QoS class, and up to eight PIRs can be associated to each SF class. For example, a QoS
class called “G711 VoIP” may include the following SFCs: “UL-G711 20 ms VoIP rtPS” and “DL-G711 20 ms VoIP rtPS”.
In turn, the SFC named “UL-G711 20 ms VoIP rtPS” may include the following rules: “Cisco VoIP UL” and “Vonage VoIP
UL”.
The software provides the ability to create, edit, and delete QoS classes that contain the following parameters:
• QoS class name
• Service Flow (SF) class name list per QoS class (up to four SF classes can be associated to each QoS class)
• Packet Identification Rule (PIR) list per SF class (up to eight PIRs can be associated to each SF class)
• Priority per rule which defines the order of execution of PIRs during packet identification process. The PIR priority is a
number in the range 0-63, with priority 63 being executed first, and priority 0 being executed last. The PIR priority is
defined within a QoS class, and can be different for the same PIR in some other QoS class. If all PIRs within one QoS
class have the same priority, the order of execution of PIR rules will be defined by the order of definition of SFCs, and
by the order of definition of PIRs in each SFC, within that QoS class.
A good example of this hierarchy is provided by the four predefined QoS classes:
1. Unlimited Best Effort
a. SF class: UL-Unlimited BE
PIR: All; PIR Priority: 0
b. SF class: DL-Unlimited BE
PIR: All; PIR Priority: 0
2. G711 VoIP
a. SF class: UL-G711 20 ms VoIP rtPS
PIR: Vonage VoIP UL; PIR Priority: 1
PIR: Cisco VoIP UL; PIR Priority: 1
b. SF class: DL-G711 20 ms VoIP rtPS
PIR: Vonage VoIP DL; PIR Priority: 1
PIR: Cisco VoIP DL; PIR Priority: 1
3. G729 VoIP
a. SF class: UL-G729 20 ms VoIP rtPS
PIR: Vonage VoIP UL; PIR Priority: 1
PIR: Cisco VoIP UL; PIR Priority: 1
b. SF class: DL-G729 20 ms VoIP rtPS
PIR: Vonage VoIP DL; PIR Priority: 1
PIR: Cisco VoIP DL; PIR Priority: 1
4. 2Mbps Video