5G • RAN

RoHC

Robust Header Compression

RFC 5795 algorithm implemented in PDCP compressing IP, UDP, and RTP headers from 40-60 bytes down to 2-3 bytes.

Technical Explanation

In VoIP and real-time streaming, IP/UDP/RTP headers (40 bytes for IPv4, 60 bytes for IPv6) exceed the size of the speech payload (32 bytes). RoHC tracks static and predictable header fields (IP addresses, sequence numbers, timestamps), transmitting only compressed 1-3 byte deltas over the air to boost spectral efficiency.

Key Functions

  • Compresses 40-60 byte IP/UDP/RTP headers down to 1-3 bytes
  • Boosts VoNR and multimedia capacity by over 60%
  • Executed natively within the 5G PDCP sublayer
Specifications
3GPP TS 38.323, IETF RFC 5795
Interfaces
Uu

Related 5G Concepts

Want to memorize 5G concepts like this one?
Study it with SuperMemo SM-2 spaced repetition flashcards.
Practice 5G Flashcards