“Truth and love will overcome lies and hatred.

Normally, I refrain from posting any non-technical content. But when those in power threatens with nuclear weapons, there is so much in stake, that I have to make an exception.

The destiny of the world we know is in our hands. As someone raised in a communist country I can imagine how difficult it might be to get all the information to decide or even to take an action. But please, take the responsibility for your live, for the future of your children.

I’m sure you can find out who is saying lies and and who is showing the truth. I’m sure you can identify attacker and defender. I’m sure you can see who is using violence to protect his life, family and land and who does use violence against others, threatens with nuclear weapons and sends elite police units against his own people. Who is so coward that even doesn’t call war a war.

Perhaps you think, that there is nothing you can do. Vaclav Havel in The Power Of The Powerless said:

“If the main pillar of the system is living a lie, then it is not surprising that the fundamental threat to it is living the truth.”

Say the truth, say it aloud and don’t collaborate with the lie. Remember Gandhi who was able to break the biggest empire of the world with his Non-cooperation movement.

Peace and love to everyone!

Rx Interface

Rx interface is often overlooked in IMS training, yet from the network core standpoint it is the most important one. It makes possible for IMS to allocate the data resources required for a media session.

Rx reference point

As we discussed in VoLTE Policy Control, the Rx Reference point is defined between P-CSCF (referred in spec as AF) and PCRF (the PCC architecture is defined in 3GPP 23.203 and 29.212). Via this interface the P-CSCF provides session information to the PCRF. The PCRF then informs the P-CSCF of traffic plane events. It can also verify that the service information provided by the P-CSCF is consistent with the operator defined policy rules. The service information is used to derive the QoS for the media service.

The PCRF can also reject the request received from the P-CSCF. In that case the PCRF indicates the result in the answer and provides to P-CSCF the service information that can be accepted.

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SMSC – 30 years later

In December 1992 there was sent the first SMS. At that time there were several different vendors working on their first SMSCs. I was lucky enough to work later with some of the engineers involved. Anyways that is an ancient history now. Since that the SMS Service and the SMSC have become a must for every mobile network. Perhaps we can go trough the general SMSC network architecture, list some of the typical features and then to discuss the SMS evolution in 5G networks.

2G/3G SMSC Architecture

The SMSC was designed as an integral part of 2G mobile network, supporting several basic message flows, which are mostly valid even in 2022:

  • Person-to-Person (P2P)
  • Application-to-Person (A2P/P2A). This was a real game changer. People in late 90s were texting (and paying) as crazy to get new ringing tones, text-frames on their monochromatic displays or at least a weather forecast or bus schedule. The A2P is still a popular way how to create a significant wholesale interconnection and also valid for MIoT (Mobile Internet of Things). Last but not least we shouldn’t forget the importance of SMS in Two-Factor-Authentication (2FA).
  • Technical enabler: Over the Air OTA messaging for (U)SIM provisioning. OTA is still critical for many operators. Another example is an IP session wake-up, which might be a key technical enabler for some Machine Type Communication MTC/MioT applications.
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