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Roaming Reference Architectures 5G NR

Roaming Reference Architectures 5G NR

What is SEPP?

SEPP is a network function designed to protect messages exchanged between different 5G networks (home and visited networks during roaming, for instance). It acts as a security gateway that filters and secures cross-border signalling traffic between network operators.

Packet Data Convergence Protocol(PDCP) NR

Packet Data Convergence Protocol(PDCP) NR

NR & LTE implements PDCP in both the User Plane and Control Plane. This is unlike UMTS, where PDCP was only found in the User Plane. The main reason for the difference is that PDCP in NR & LTE takes on the role of security, i.e. encryption and integrity.

5G MAC Protocol

5G MAC Protocol

Medium Access Control (MAC) protocol specification written in (3GPP TS 38.321).     MAC is a protocol layer above the physical layer and below the RLC layer. The ‘Medium Access Control’ (MAC) layer receives both the user plane and control plane data from the set of logical channels provided by the RLC layer. Multiplexes and…

Architecture for interworking between 5GS and EPC/E-UTRAN

Architecture for interworking between 5GS and EPC/E-UTRAN

  N26 interface is an inter-CN interface between the MME and 5GS AMF in order to enable interworking between EPC and the NG core. Support of the N26 interface in the network is optional for interworking. N26 supports a subset of the functionalities (essential for interworking) that are supported over S10. PGW-C + SMF and…

5G NR Initial Access

5G NR Initial Access

How 5G NR initial Cell Search process work? For the initial access case (idle mode), the UE should start by the cell search procedure. By using the PSS, SSS, and specific synchronization algorithms, the UE can estimate and correct the frequency and time offsets.    Cell Search The UE searches for a specific frequency based…

5G NR  Protocol Test

5G NR Protocol Test

CafeTele 5G NR QUIZ Test, Participate in the 5G NR QUIZ and feedback us about your experience with the CafeTele Quiz segment.     Check some other Quiz from Cafetele https://cafetele.com/quiz-5g-nr-architecture/

LTE Channel

LTE Channel

LTE Downlink Channels Physical Downlink Shared Channel (PDSCH) Carries the DL-SCH and PCH. DL-SCH contains actual user data. Physical Downlink Control Channel (PDCCH) Informs the UE about the resource allocation of PCH and DL-SCH, and HARQ information related to DL-SCH. Carries the uplink scheduling grant. Physical HARQ Indicator Channel (PHICH) Carries ACK/NACKs in response to…

VOLTE SIP Message

VOLTE SIP Message

First we have to understand what is SIP ?  In an IMS network, Session Initiation Protocol (SIP) messages are exchanged between UEs using signaling PDP contexts through the PS domain of the LTEnetwork. Similarly, media streams (voice/video) are transmitted using media PDP contexts. Like common interactive PDP contexts, media PDP contexts do not require special…