Newest courseRAN Optimisation & Performance

Why the call does not get in, why it drops, and why it is slow — told apart on evidence, with the denominator checked before the verdict.

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Bite-size 5G & 6G lessons with hands-on labs — start learning free, no signup.

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4G LTE Essentials

IMS components: P-CSCF, S-CSCF, I-CSCF

interactive3 min

Lesson 22 of 33

Card 1 of 617%

Warm-up: Guess before you learn

Try these first, even if you're not sure. Guessing primes your brain.

A UE enters an IMS network. Which node should it contact first?

Each subscriber has one assigned serving node. Who locates it?

A voice call needs a GBR bearer. Which IMS node requests it?

Answer all 3to continue — it's OK to be wrong.

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