Packet Data Convergence Protocol: Difference between revisions
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I think this is more correct, because 5G NR is to 5G the same as an E-UTRA to LTE |
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'''Packet Data Convergence Protocol''' ('''PDCP''') is specified by [[3GPP]] in TS 25.323<ref>{{Cite web|url=http://www.3gpp.org/ftp/Specs/html-info/25323.htm|title=TS 25.323|website=www.3gpp.org|access-date=2019-03-14}}</ref> for [[UMTS]], TS 36.323<ref>{{Cite web|url=http://www.3gpp.org/ftp/Specs/html-info/36323.htm|title=TS 36.323|website=www.3gpp.org|access-date=2019-03-14}}</ref> for [[LTE_(telecommunication)|LTE]] and TS 38.323<ref>{{Cite web|url=http://www.3gpp.org/ftp/Specs/html-info/38323.htm|title=TS 38.323|website=www.3gpp.org|access-date=2019-03-14}}</ref> for [[5G]]. PDCP is located in the Radio Protocol Stack in the UMTS/LTE/5G [[air interface]] on top of the [[Radio Link Control|RLC]] layer. |
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{{cleanup-date|March 2006}} |
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PDCP provides its services to the [[Radio Resource Control|RRC]] and user plane upper layers, e.g. [[Internet Protocol|IP]] at the [[User equipment|UE]] or to the relay at the base station. The following services are provided by PDCP to upper layers: |
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'''PDCP''' stands for Packet Data Convergence Protocol. |
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* transfer of user plane data; |
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It is one of the layer of the Radio Traffic Stack in UMTS and performs |
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* transfer of control plane data; |
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* header compression; |
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and maintenance of sequence numbers for Radio Bearers which are |
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* ciphering; |
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configured for loseless SRNS relocation. |
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* integrity protection. |
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The header compression technique can be based on either IP header compression (<nowiki>RFC 2507</nowiki>) or [[Robust Header Compression]] (<nowiki>RFC 3095</nowiki>). If '''PDCP''' is configured for ''No Compression'' it will send the IP Packets without compression; otherwise it will compress the packets according to its configuration by upper layer and attach a '''PDCP''' header and send the packet. |
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The compression technique can be based on either RFC 2507 or |
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RFC 3095.RFC 1144 can also be used for some help but it's not |
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used now a days, still it gives you the idea how does the compression/decompression techniques look like. |
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Different header formats are defined, dependent on the type of data to be transported. In LTE, there are e.g. header formats for Control Plane PDCP Data [[Protocol data unit|PDU]] with long PDCP SN (12 bits), for User plane PDCP Data PDU with short PDCP SN (7 bits) and others. |
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If PDCP is configured for No Compression it will send the |
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IP Packets without compression else it will compress the |
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packets according to it's configuration by upper layer and |
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attach PDCP header and send the packet.It uses the service |
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provided by lower layer called RLC. |
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== References == |
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PDCP header consists of two fields PID and PDU TYPE.The PDU |
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{{Reflist}} |
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type field indicates whether the PDU is Data PDU or Seq Num PDU. |
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The PID field value indicates header compression protocol type |
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used and packet type or CID. |
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== External links == |
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* {{IETF RFC|2507|link=no}} IP header compression |
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* {{IETF RFC|3095|link=no}} Robust Header Compression |
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[[Category:Mobile telecommunications standards]] |
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[[Category:3GPP standards]] |
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[[Category:UMTS]] |
[[Category:UMTS]] |
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[[Category:5G (telecommunication)]] |
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Latest revision as of 07:05, 23 November 2021
Packet Data Convergence Protocol (PDCP) is specified by 3GPP in TS 25.323[1] for UMTS, TS 36.323[2] for LTE and TS 38.323[3] for 5G. PDCP is located in the Radio Protocol Stack in the UMTS/LTE/5G air interface on top of the RLC layer.
PDCP provides its services to the RRC and user plane upper layers, e.g. IP at the UE or to the relay at the base station. The following services are provided by PDCP to upper layers:
- transfer of user plane data;
- transfer of control plane data;
- header compression;
- ciphering;
- integrity protection.
The header compression technique can be based on either IP header compression (RFC 2507) or Robust Header Compression (RFC 3095). If PDCP is configured for No Compression it will send the IP Packets without compression; otherwise it will compress the packets according to its configuration by upper layer and attach a PDCP header and send the packet.
Different header formats are defined, dependent on the type of data to be transported. In LTE, there are e.g. header formats for Control Plane PDCP Data PDU with long PDCP SN (12 bits), for User plane PDCP Data PDU with short PDCP SN (7 bits) and others.
References
[edit]- ^ "TS 25.323". www.3gpp.org. Retrieved 2019-03-14.
- ^ "TS 36.323". www.3gpp.org. Retrieved 2019-03-14.
- ^ "TS 38.323". www.3gpp.org. Retrieved 2019-03-14.