QoS Profile configuration in GGSN

[assassinhp]

Can you please explain the purpose of configuration QoS Profile (consists of parameters refer to the traffic class model in 3GPP 23.107)? I mean how is it different from the QoS Profile that is sent from UE in PDP Context Activation ?
Thank you so much.

[Kirill Kucherov]

Hi,

QoS Profiles (that is how they are named at NSN) on RNC, SGSN, GGSN are created for mapping of UMTS QoS-s (TC + THP + ARP) to transport QoS-s - i.e. queues: EF, AF41.... BE, if you need it to be different from default.

And, by the way, UE QoS parameters are stored at HLR and SGSN/GGSN took them from there during GPRS Attach and Context Activation processes by communicating with it.

Is this what was you question about?

[assassinhp]

So can I configure the QoS attributes (refer to 3gpp 23.107) in UE or measure tools. If not, how can I capture the file (on which interface and by what )?
Thank you so much.

[Kirill Kucherov]

It depends on what attributes exactly you need.

Most of them are configured at HLR (for instance, GBR, THP, ARP) in Subscriber or QoS Profiles.
Some of them can be modified by SGSN and GGSN according to defined rules. Just for instance: GGSN can change TC for UE according to APN it connects to during PDP Context Activation, SGSN can set Pre-emptioning capability for UE according to ARP and other parameters from HLR during RAB establishment.
However, some attributes are not configurable until defined 3GPP releases. For example, NSN SGSN does not support changes of Pre-emptioning capability attribute and some other until Release 9.

If you do not have an opportunity to look at HLR profiles you can capture traffic either by GGSN tools (cannot advice which exactly) or on routers interfaces which carry GTP-C traffic for instance by Wireshark - look for PDP Context Activation messages. If you have Huawei RNCs there are some tools there as well, but not in NSN RNCs - look for RAB establishment response messages.

[assassinhp]

Thanh you so much. I appriciate your answer. Because I am measuring the End user QoS over UMTS, including: (One way delay, jitter and information loss refer to 3GPP 22.105). I am searching for a tool to simulating the service to GGSN. To do this I must create QoS Profile in the tool (UE), include the following attributes:
- Maximum bitrate, delivery order, Maximum SDU Size, SDU Format information, SDU error ratio, Residual bit error rate, Delivery of erroneous SDUs, Transfer delay, Guaranteed bit rate, traffic handling priority, allocation / retention priority, Source statistics descriptor, Signalling indication and Evolved allocation/retention priority.
Are all the above attributes (refer to 3GPP TS 23.107) saved in QoS Profile in HLR? However, I am confusing one problem:
- Can I configure some attributes from UE (or simulating tool) for example: Maximum bitrate, SDU error ratio, Residual Bit rate, etc. The purpose is to simulate a particular service such as: Audio, converstional, telnet ,.. Because I know that UE must send a QoS Profile in PDP Context Activation and I think I can configure from UE or UE suggest an value for each attribute such as Maximum bit rate = 128kbps, Delivery Order = Yes, etc(that's why I confuse your explain that some attributes are configured at HLR).
Thank you so much.

[Kirill Kucherov]

You can create test Subscriber and QoS Profiles on HLR with attributes you need for every service test (this as was done at our net) - either different profiles for different test USIMs or changing one profile every time you change service testing.

Do not forget that within QoS Profiles on SGSN and GGSN you can map this categories (based on 3GPP TS 23.107 attributes) to defined queues at transport which will define traffic handling within IP/MPLS and MetroEthernet and define delays and packet loss as well and even in the first turn.

UE itself do not send any QoS Profile - it does not have any - it just sends its equipment capabilities, APN it is going to connect and information about type of originating service. Then SGSN communicate with HLR regarding attributes of user asking for attach, and receive them from HLR. Then GGSN does some additional checking and finilise parameters to use for current UE. After SGSN attached the user and GGSN activated PDP context SGSN establishes RAB sending all negotiated parameters to RNC which take them into consideration modifying Radio Bearers and choosing traffic handling behaviour for transport network on RAN.

I've tried to be laconic :)

[assassinhp]

Thanh you. However, there is still one problem: You mean "UE only send equipment capabilities and APN connect and inform about type of orginating service". The question is that how can APN know exactly about the service of UE because UE can use Web Browsing, video streaming or FTP service and many others. And one more, because UE also send "Activate PDP COntext Request" in RRC INITIAL DIRECT TRANSFER message to RNC. Does this message include QoS profile that UE require for service?
I hope you don't feel uncomfortable because some of my stupid questions. Thank you.

[assassinhp]

You can create test Subscriber and QoS Profiles on HLR with attributes you need for every service test (this as was done at our net) - either different profiles for different test USIMs or changing one profile every time you change service testing.

Do not forget that within QoS Profiles on SGSN and GGSN you can map this categories (based on 3GPP TS 23.107 attributes) to defined queues at transport which will define traffic handling within IP/MPLS and MetroEthernet and define delays and packet loss as well and even in the first turn.

UE itself do not send any QoS Profile - it does not have any - it just sends its equipment capabilities, APN it is going to connect and information about type of originating service. Then SGSN communicate with HLR regarding attributes of user asking for attach, and receive them from HLR. Then GGSN does some additional checking and finilise parameters to use for current UE. After SGSN attached the user and GGSN activated PDP context SGSN establishes RAB sending all negotiated parameters to RNC which take them into consideration modifying Radio Bearers and choosing traffic handling behaviour for transport network on RAN.

I've tried to be laconic :)

Can you please answer one more question. Because you said that "Do not forget that within QoS Profiles on SGSN and GGSN you can map this categories (based on 3GPP TS 23.107 attributes) to defined queues at transport which will define traffic handling within IP/MPLS and MetroEthernet and define delays and packet loss as well and even in the first turn.". Can you explain more cleary about how to define delays packet loss .
P/S: APN in this case is exactly SGSN, right ?
Thank you so much.

[Kirill Kucherov]

When UE sends RRC Initial Direct Transfer Message it says within it the type of originating service based on range of allowed values of the field establishment cause: f.e. - Conversational Voice call - I do not remember exact values. As well it sends an information about APN configured on the device by user which he is going to use. At HLR for every user can be defined a few profiles with allowed APNs to use. According to the APN requested - i.e. subscriber profile - there is a record about QoS profile which defines traffic type to use - Conversational, Streaming, Interactive, Background. In this way Core NE knows which APN and which traffic class to use for the UE. This the static configuration which is used more frequently.

Additionally, there are features - such as Deep Packet Inspection and some other on GGSN, which could help to differentiate services and handle user traffic in different way regarding service user require dynamicly within one APN adn without reconnecting to different APN manually.

[Kirill Kucherov]

P/S: APN in this case is exactly SGSN, right ?


No, these are entities on GGSN.



Can you explain more cleary about how to define delays packet loss .

I meant that delay, jitter and packet losses depend on how you build your transport network and how you set QoS model on it - conversational traffic needs higher priority to be delivered on time, data needs to be ensured of integrity, video - of constant jitter. According to these requirements QoS model on transport network should be developed allocating different guaranteed BW for different queues. These queues are defined by EF, AF41.... BE - PHB - which correspond to DSCP on L3 (there are other lables on L2 and on MPLS). So transport network QoS is the key point of the question which traffic (i.e. service) will experience which delay, jitter and losses in case of congestion on the network, and which will be prioritised. Generally, if transport network QoS is fully designed according to all requirement you could use default mapping from UMTS QoS to transport QoS. If not you can tune it to take a better effect, use different queues for different services and different users (if you need). By the way, an opportunity to create QoS Profiles to use them on interfaces on NSN equipment as I remember are under license control so cost money.

[assassinhp]

Thank you so much. I have many questions about this because I want to measure the quality of UMTS Network with individual services. I refer to 3GPP 23.107 and I think I should evaluate with UMTS Bearer Service (Following the below image)
28400
First, I know that UMTS BS have 4 class traffic with a set of attributes (or QoS Profile). I mean to measure and evaluate these attributes with different services. But from your answer, I think that is impossible.
Then, I read 3GPP TS 22.105 and I know that Bearer Service can be evaluated by One way delay, Delay variation and Information loss. To measure these parameters from End user to cover all UMTS BEarer (not only transportation network), I must simulate different services from UE to GGSN by configure many QoS Profies in measurement tools (but from your answer that is also impossible).
So, do you have experience in measuring the Quality of UMTS, especially in measuring the 3 parameters (OWD, Delay variation and information loss) from UE to GGSN?
Thank you so much.

[assassinhp]

Can you explain more clearly about Transport Network, you mean "Mobile backhaul" from NodeB to RNC or from UTRAN to CN or overall UMTS Bearer (from UE to GGSN). ??