Thank you for your positive feedback and great question! In a typical 4G/5G network architecture, the charging function is primarily handled by the PCRF (Policy and Charging Rules Function) rather than the MTAS (Multimedia Telephony Application Server). The PCRF is responsible for policy control decision-making and flow-based charging control functionalities. It provides network control regarding service data flow detection, gating, QoS, and flow-based charging towards the Policy and Charging Enforcement Function (PCEF). The MTAS, on the other hand, is mainly responsible for handling multimedia telephony services like Voice over LTE (VoLTE) or Voice over New Radio (VoNR). While it may interact with charging systems, it's not the primary entity responsible for charging decisions. However, it's worth noting that in 5G networks, these functions are evolving. The PCRF is being replaced by the Policy Control Function (PCF), and charging is handled by the Charging Function (CHF) as part of the Service Based Architecture (SBA).
Very helpful Mohamed, way to go!! In case of IMS user plane(QCI 1), the RLC mode is UM -which means no RLC retransmissions- but in MAC layer HARQ retransmissions can occur. Is it correct? A second question : Are the codecs supported by a Ue dependent on radio conditions ? For example in medium to bad radio conditions only AMR -WB or AMR-NB codecs can be activated and EVS codec in good radio conditions. Thank you
Correct only HAQR retransmission for qci1 and regarding the codec part i am not 100% sure of the answer but as per my understanding codec depends on on 2 factors( technology and UE capabilities) for example if UE as server by 2G definitely only AMR NB will be used
Hi Mohamed i have 3 questions: a) Is there any timer that measures the time during which the user is silent and then enables the transmission of SID frames ? b) Why S-CSCF invokes the MTAS and not the HSS for the user status, if the user is allowed to perform the call ? c) Given that RTP(QCI 1) packets are transmitted every 20msec, how often IMS signaling packets with QCI 5 are transmitted ? Thank you
Hi Geroge, Please seen my answer below: (1) As I understand there is no timer to control the SID Frames; it is mainly identified based on the SID Transmitted intervals which is 160ms and the frame size is always fixed to 56 bits for AMR voice coding rates and 64 bits for EVS voice coding rates (2) Good questions; I am not really sure about why HSS is not being involved but in all cases MTAS invoking the MTAS for MO & MT Services are one the main function of MTAS Server and I believe HSS should offer the same functionality and might get involved at some stages but I am not sure about the scenarios. I will let you know if I find any direct answer for your questions (3) I think there is no fixed duration for SIP Signaling as this is event based and on demand signaling, for example when the user sent or receive SIP Invite or any other events but it is not something being exchanged all over the call.
Mashaa2 allah habibe ya abo Adawy ya negm ngom el optimization :)
Habeby ya Mr shehata; lek wa7sha ya ma3lem
Hello Adawy,
great session as usual, just a quick question, the MTAS is responsible for charging and credit or PCRF?
Thank you for your positive feedback and great question! In a typical 4G/5G network architecture, the charging function is primarily handled by the PCRF (Policy and Charging Rules Function) rather than the MTAS (Multimedia Telephony Application Server).
The PCRF is responsible for policy control decision-making and flow-based charging control functionalities. It provides network control regarding service data flow detection, gating, QoS, and flow-based charging towards the Policy and Charging Enforcement Function (PCEF).
The MTAS, on the other hand, is mainly responsible for handling multimedia telephony services like Voice over LTE (VoLTE) or Voice over New Radio (VoNR). While it may interact with charging systems, it's not the primary entity responsible for charging decisions.
However, it's worth noting that in 5G networks, these functions are evolving. The PCRF is being replaced by the Policy Control Function (PCF), and charging is handled by the Charging Function (CHF) as part of the Service Based Architecture (SBA).
I really appreciate this, u r learning us very valuable lectures. Thanks dear Mohamed Eladawi.
You’re welcome; thanks a lot ahmed for your feedback.
Great content! Please keep posting the rest of the series.
Thank you; i will do no worries
Thank you Adawy.
بارك الله فيك
You’re very welcome
Great content! Please keep posting the rest of the series and upload the document.
Sure; i will upload the document after all videos are posted. Thanks
Great
Good... Thank you so much for the information 👏
Thank you
this is great content Mohamed , thanks!
Thanks a lot, Remzi; i am happy you like it
Very helpful Mohamed, way to go!! In case of IMS user plane(QCI 1), the RLC mode is UM -which means no RLC retransmissions- but in MAC layer HARQ retransmissions can occur. Is it correct?
A second question : Are the codecs supported by a Ue dependent on radio conditions ? For example in medium to bad radio conditions only AMR -WB or AMR-NB codecs can be activated and EVS codec in good radio conditions. Thank you
Correct only HAQR retransmission for qci1 and regarding the codec part i am not 100% sure of the answer but as per my understanding codec depends on on 2 factors( technology and UE capabilities) for example if UE as server by 2G definitely only AMR NB will be used
Thanks for this very useful training
You’re welcome. Thanks for your feedback
Hi Mohamed i have 3 questions: a) Is there any timer that measures the time during which the user is silent and then enables the transmission of SID frames ? b) Why S-CSCF invokes the MTAS and not the HSS for the user status, if the user is allowed to perform the call ? c) Given that RTP(QCI 1) packets are transmitted every 20msec, how often IMS signaling packets with QCI 5 are transmitted ? Thank you
Hi Geroge,
Please seen my answer below:
(1) As I understand there is no timer to control the SID Frames; it is mainly identified based on the SID Transmitted intervals which is 160ms and the frame size is always fixed to 56 bits for AMR voice coding rates and 64 bits for EVS voice coding rates
(2) Good questions; I am not really sure about why HSS is not being involved but in all cases MTAS invoking the MTAS for MO & MT Services are one the main function of MTAS Server and I believe HSS should offer the same functionality and might get involved at some stages but I am not sure about the scenarios. I will let you know if I find any direct answer for your questions
(3) I think there is no fixed duration for SIP Signaling as this is event based and on demand signaling, for example when the user sent or receive SIP Invite or any other events but it is not something being exchanged all over the call.
Great information. Thanks
You’re very welcome, thanks for commenting and sharing this feedback
Thank you so much for the information ☺️
You’re welcome. Thank you
thank you very much adawy
You’re welcome. Thanks for sharing your feedback
Thanks for this series, if possible please add english subtitles..
You’re welcome; i think you can enable it; it should be available by default
It’s enabled by default
عاشت ايدك
حبيبي؛ تسلم يا كريم
Good
Thanks
thank you so much can u share the ppt as well?
Hi Ali; i will share part of the training documents if not all at the end of the full training at the below link
www.mohamedeladawi.com