What is e-RAB?
An E-RAB (E-UTRAN Radio Access Bearer) refers to the concatenation of an S1 bearer and the corresponding radio bearer. When an E-RAB exists, there is a one-to-one mapping between this E-RAB and an EPS bearer of the Non Access Stratum.
Which network entity initiates the RAB establishment procedure?
Establishment and modification of the E-RAB dedicated bearer are initiated by the MME entity by sending the E-RAB SETUP/MODIFY REQUEST messages.
What is S1AP in LTE?
S1AP provides the signalling service between E-UTRAN and the evolved packet core (EPC) and has following functions: E-RAB management function. Initial Context Transfer function. UE Capability Info Indication function.
What is ERAB failure in lte?
Consequently, eNB sends Initial Context Setup Failure to the MME resulting in ERAB setup failure. This happens if the security configuration on the eNB is not supported by the UE or sometimes it can happen if the UE cannot handle both the Security Mode Command and the RRC Connection Reconfiguration together.
What is RRC and RAB?
Sending requests and receipts is part of signaling, or the RRC. The shipment of purchases is the data part, or the RAB. In our scenario, the RRC are the Rails, and RAB is the full service of sending data between the UE and the CN. RRC: Radio Resource Control. RAB: Radio Access Bearer.
What is e-Rab drop rate?
As a result of downlink and uplink, ERAB Call Drop Rate is 0.05 and 72.41, respectively.
What is LTE RAB?
RAB stands for Radio Access Bearer. AS entity provides NAS to take care of information transfer between UE and Core Network(CN). This is known as RAB. Figure-2 depicts RAB across the UMTS system end to end from UE(i.e. mobile) to MSC/SGSN.
What are S1AP messages?
The S1 Application Protocol (S1AP) provides the control plane signalling between E-UTRAN and evolved packet core (EPC). The used interface is S1-MME which is located between eNB and MME. The services provided by the S1AP are divided to UE associated and non UE associated.
What is NAS and as in LTE?
Non-access stratum (NAS) is a functional layer in the UMTS and LTE wireless telecom protocol stacks between the core network and user equipment. This layer is used to manage the establishment of communication sessions and for maintaining continuous communications with the user equipment as it moves.
What is e Rab drop rate?
What is multi Rab in UMTS?
The maximum data rate supported by the Interactive RAB (Packet Switched, PS) is 384 kbit/s in the downlink and 64 kbit/s in the uplink, making it ideal for email or web browsing. It is also possible to use the speech RAB together with the interactive RAB that is usually called a MultiRAB.
What is the E-Rab ID value?
The E-RAB ID value used at S1 and X2 interfaces to identify an E-RAB is the same as the EPS Bearer ID value used to identify the associated EPS Bearer. The description is perfect and well structured, as always. Keep up the good work!
Is E-Rab ID part of S1AP message sent by Mme to ENB?
Spec 36.413 says that ERABList ( in InitialContextSetupRequest or E-RAB Setup Request ) is sent by MME to eNB and one of the mandatory parameters of this list is E-RAB Id. Moreover, eNB would never know what EPS Bearer ID is because it is generated by MME and sent to UE in NAS message. It is not part of S1ap Message sent to eNB.
What are the factors affecting the Rab multiple?
• Any given RAB multiple could be due to a range of factors – revenue, expenditure, or cost of capital. We should always seek to understand the drivers in any specific case. • We should be cautious about any feature of the regulatory regime which leads to systematic over- compensation.
What is an ERAB attempt in Mme?
Once the MME receives this message and it decides that a bearer is required, it will send an Initial Context Setup Request to the eNB. This message is considered as the ERAB Attempt as it contains the bearers to be added along with their QCI values.