LTE Arsitektur

Long Term Evolution atau yang lebih kenal dengan  LTE secara garis besar dapat dilihat menjadi dua bagian. Yang pertama merupakan evolusi dari Universal Mobile Telecommunication System (UTRAN) menjadi Evolved UTRAN (EUTRAN). Bagian kedua adalah merupakan evolusi dari aspek non radio yaitu System Architecture Evolution (SAE) yang didalamnya terdapat Evolved Packet Core (EPC). Evolusi keduanya, LTE dan EPC dinamakan sebagai Evolved Packet System (EPS)

Didalam EPC terdapat beberapa NE, yaitu :

• Serving Gateway (SGW)
• Packet Data Network (PDN) Gateway (PGW)
• Mobility Management Entity
• Home Subscriber Server (HSS)
• Policy Control and Charging Rules Function (PCRF)

Penjelasan node dalam EPC akan dijelaskan tetap dalam bahasa Inggris, karena takut salah mengartikan dan kurang lengkap, penjelasanya sebagai berikut :

• PCRF – The Policy Control and Charging Rules Function is responsible for policy control
  decision-making, as well as for controlling the flow-based charging functionalities in the Policy
  Control Enforcement Function (PCEF), which resides in the P-GW. The PCRF provides the
  QoS authorization (QoS class identifier [QCI] and bit rates) that decides how a certain data flow
  will be treated in the PCEF and ensures that this is in accordance with the user’s subscription
  profile.
• HSS – The Home Subscriber Server contains users’ SAE subscription data such as the EPS-subscribed QoS profile and any access restrictions for roaming. It also holds information about the PDNs to which the user can connect. This could be in the form of an access point name (APN) (which is a label according to DNS naming conventions describing the access point to the PDN) or a PDN address (indicating subscribed IP address(es)). In addition the HSS holds dynamic information
  such as the identity of the MME to which the user is currently attached or registered. The HSS may
  also integrate the authentication center (AUC), which generates the vectors for authentication and
  security keys.
• P-GW – The PDN Gateway is responsible for IP address allocation for the UE, as well as QoS
  enforcement and flow-based charging according to rules from the PCRF. It is responsible for the
  filtering of downlink user IP packets into the different QoS-based bearers. This is performed based
  on Traffic Flow Templates (TFTs). The P-GW performs QoS enforcement for guaranteed bit rate
  (GBR) bearers. It also serves as the mobility anchor for interworking with non-3GPP technologies
  such as CDMA2000 and WiMAX® networks.
• S-GW – All user IP packets are transferred through the Serving Gateway, which serves as the
  local mobility anchor for the data bearers when the UE moves between eNodeBs. It also retains
  the information about the bearers when the UE is in the idle state (known as “EPS Connection
  Management — IDLE” [ECM-IDLE]) and temporarily buffers downlink data while the MME
  initiates paging of the UE to reestablish the bearers. In addition, the S-GW performs some
  administrative functions in the visited network such as collecting information for charging (for
  example, the volume of data sent to or received from the user) and lawful interception. It also
  serves as the mobility anchor for interworking with other 3GPP technologies such as general
  packet radio service (GPRS) and UMTS.
• MME – The Mobility Management Entity (MME) is the control node that processes the signaling
  between the UE and the CN. The protocols running between the UE and the CN are known as
  the Non Access Stratum (NAS) protocols.

 

Kalau anda perhatikan gambar diatas, mungkin akan ada pertanyaan siapa yang akan menghandle service voice, sebelum teknologi LTE service CS akan dihandle oleh MSS/MSC/MGW. Namun pada LTE tidak ada service CS seperti generasi sebelumnya, service voice akan ditumpangkan didalam IP, yang menjadi VoIP.

Semoga dengan penjelasan diatas kita bisa mendapatkan informasi garis besar mengenai Arsitektur dan Teknologi LTE