The purpose of the quality of service information element is to specify the QoS parameters for a PDP context.

The QoS IE is defined to allow backward compatibility to earlier version of Session Management Protocol.

The quality of service is a type 4 information element with a minimum length of 14 octets and a maximum length of 16 octets. The QoS requested by the MS shall be encoded both in the QoS attributes specified in octets 3-5 and in the QoS attributes specified in octets 6-14.

In the MS to network direction and in the network to MS direction the following applies:

-     Octets 15 and 16 are optional. If octet 15 is included, then octet 16 shall also be included.

-     A QoS IE received without octets 6-16, without octets 14-16, or without octets 15-16 shall be accepted by the receiving entity.

NOTE:      This behavior is required for interworking with entities supporting an earlier version of the protocol, or when the Maximum bit rate for downlink is negotiated to a value lower than 8700 kbps.

The quality of service information element is coded as shown in figure 10.5.138/3GPP TS 24.008 and table 10.5.156/3GPP TS 24.008.

 

8

7

6

5

4

3

2

1

Quality of service IEI

octet 1

Length of quality of service IE

Octet 2

0              0 spare

Delay class

Reliability class

octet 3

Peak throughput

0 spare

Precedence class

octet 4

0              0              0 spare

Mean throughput

octet 5

Traffic Class

Delivery order

Delivery of erroneous SDU

Octet 6

Maximum SDU size

Octet 7

Maximum bit rate for uplink

Octet 8

Maximum bit rate for downlink

Octet 9

Residual BER

SDU error ratio

Octet 10

Transfer delay

Traffic Handling priority

Octet 11

Guaranteed bit rate for uplink

Octet 12

Guaranteed bit rate for downlink

Octet 13

0              0              0 spare

Signal-ling Indicat-ion

Source Statistics Descriptor

Octet 14

Maximum bit rate for downlink (extended)

Octet 15

Guaranteed bit rate for downlink (extended)

Octet 16

 

Figure 10.5.138/3GPP TS 24.008: Quality of service information element

Table 10.5.156/3GPP TS 24.008: Quality of service information element

Reliability class, octet 3 (see 3GPP TS 23.107)
Bits
3 2 1
In MS to network direction:
0 0 0       Subscribed reliability class
In network to MS direction:
0 0 0       Reserved
In MS to network direction and in network to MS direction:
0 0 1       Acknowledged GTP, LLC, and RLC; Protected data
0 1 0       Unacknowledged GTP; Acknowledged LLC and RLC, Protected data
0 1 1       Unacknowledged GTP and LLC; Acknowledged RLC, Protected data
1 0 0       Unacknowledged GTP, LLC, and RLC, Protected data
1 0 1       Unacknowledged GTP, LLC, and RLC, Unprotected data
1 1 1       Reserved

All other values are interpreted as Unacknowledged GTP and LLC; Acknowledged RLC, Protected data in this version of the protocol.

Delay class, octet 3 (see 3GPP TS 22.060 and 3GPP TS 23.107)
Bits
6 5 4
In MS to network direction:
0 0 0       Subscribed delay class
In network to MS direction:
0 0 0       Reserved
In MS to network direction and in network to MS direction:
0 0 1       Delay class 1
0 1 0       Delay class 2
0 1 1       Delay class 3
1 0 0       Delay class 4 (best effort)
1 1 1       Reserved

 

 

All other values are interpreted as Delay class 4 (best effort) in this version
of the protocol.

Bit 7 and 8 of octet 3 are spare and shall be coded all 0.

Precedence class, octet 4 (see 3GPP TS 23.107)
Bits
3 2 1
In MS to network direction:
0 0 0       Subscribed precedence
In network to MS direction:
0 0 0       Reserved
In MS to network direction and in network to MS direction:
0 0 1       High priority
0 1 0       Normal priority
0 1 1       Low priority
1 1 1       Reserved

 

 

All other values are interpreted as Normal priority in this version of the protocol.

Bit 4 of octet 4 is spare and shall be coded as 0.

Peak throughput, octet 4 (see 3GPP TS 23.107)
Bits
8 7 6 5
In MS to network direction:
0 0 0 0                    Subscribed peak throughput
In network to MS direction:
0 0 0 0                    Reserved
In MS to network direction and in network to MS direction:
0 0 0 1                    Up to 1 000 octet/s
0 0 1 0                    Up to 2 000 octet/s
0 0 1 1                    Up to 4 000 octet/s
0 1 0 0                    Up to 8 000 octet/s
0 1 0 1                    Up to 16 000 octet/s
0 1 1 0                    Up to 32 000 octet/s
0 1 1 1                    Up to 64 000 octet/s
1 0 0 0                    Up to 128 000 octet/s
1 0 0 1                    Up to 256 000 octet/s
1 1 1 1                    Reserved

All other values are interpreted as Up to 1 000 octet/s in this
version of the protocol.

Mean throughput, octet 5 (see 3GPP TS 23.107)
Bits
5 4 3 2 1

Yes QoS is very important ............

Sound good.......Thx