Prowid course material: https://kurslar.prowid.com/en/index.php?id=lesson&m=3035
ISDN: BRI and PRI, Q.921 and Q.931 · Layer 3: Q.931 (DSS1)
Bearer capability: speech, 3.1 kHz audio, 64 kbit/s unrestricted
🔒 This is the beginning of the lesson. The full lesson is available with a subscription.
