Richard Li discusses limitations of IPv4 and IPv6 for 5G, B5G, and 6G mobile network applications. He notes that IPv4/IPv6 yields huge bandwidth waste for mMTC, UCBC, HCS, and short texts due to large packet overhead. Additionally, IPv4/IPv6 cannot guarantee key performance indicators like latency and packet loss required for uRLLC and RTBC. As an alternative, Li proposes an incremental evolution of IPv4/IPv6 that includes flexible addressing systems, geography-based addressing, and integration of satellite and terrestrial networks to expand its applicability for future applications and services.

1. Futurewei Technologies, Inc.
Limitations of IPv4/IPv6 for 5G/B5G/6G Mobile Network Applications
Richard Li
Chief Scientist, Network Technologies,
Futurewei, USA
IFIP Networking 2021
Panel: BEYOND 5G SERVICES: PRESENT TECHNOLOGICAL LIMITATIONS & FUTURE OPPORTUNITIES
Wednesday, June 23, 2021

2. 2
Does IPv4/IPv6 have any limitation for 5G/B5G/6G applications and services?
eMBB
mMTC uRLLC
UCBC RTBC
HCS
eMBB
mMTC uRLLC
6G
2030s
4G
2010s 2020s 2025
IPv4 IPv6
1981 1995
5G
B5G
? ? ?
? ? ?
Do we have any
other choice?

3. Page 3
IPv4/v6 has been used as a solution for mobile network applications
App (user)
TCP (user)
IP (user)
PDCP
RLC
MAC
PHY
App (user)
TCP (user)
IP (user)
PDCP
RLC
MAC
PHY
App (user)
TCP (user)
IP (user)
GTP-U (S1)
UDP (Nwk)
IP (Nwk)
IP/MPLS
Backhaul
Eth/Nwk
App (user)
TCP (user)
IP (user)
GTP-U (S1)
UDP (Nwk)
IP (Nwk)
IP/MPLS
Backhaul
Eth/Nwk
App (user)
TCP (user)
IP (user)
Radio Access Network
Fixed IP Backhaul Network
IP/MPLS
Backhaul
Eth/Nwk
IP/MPLS
Backhaul
Eth/Nwk
Core/MEC

4. Page 4
The current IP solution yields huge bandwidth waste for mMTC, UCBC, HCS, and Short Texts
𝐼𝑃 𝐵𝑎𝑐𝑘ℎ𝑎𝑢𝑙 𝑡𝑟𝑎𝑛𝑠𝑝𝑜𝑟𝑡 𝑂𝐻 % =
(𝑃𝑎𝑡ℎ𝑜ℎ)
(𝑆𝑡𝑑ℎ𝑑𝑟 + 𝑃𝑎𝑡ℎ𝑜ℎ + 𝑈𝑠𝑒𝑟 𝐷𝑎𝑡𝑎)
0
10
20
30
40
50
60
70
80
90
100
OH 1-hop OH 4-hop OH 10-hop OH 20-hop
4-byte: Overhead in % of total length
MPLS SR-MPLS SRv6
MPLS bytes MPLS-SR bytes SRV6 bytes
IPv6 Encap 40
SRH header 8
Transport Labels 4 to 12
ServiceLabel 4 ServiceLabel 4
Outer IPv4 (for GTP) 20 Outer IPv4 (for GTP) 20 ServiceSID 16
UDP Hdr 4 UDP Hdr 4 UDP Hdr 8
GTP 12 GTP 12 GTP 12
Inner User IP 20 Inner User IP 20 Inner User IP 20
User Transport 4 User Transport 4 User Transport 4
User Payload 4 to 1200 User Payload 4 to 1200 User Payload 4 to 1200
16 x SID
count
(upto 30)
transport SID
Transport Labels
4 x SID count
(upto 30)
44-52 44-160 100-564
Extra Header
❖ MPLS-SR and SRv6 overheads go up with the number of hops
❖ Protocol efficiency with regards to small packets is very low, and can be as low as below 10%
• Connected Industries and Industrial Control: Control Command (1 byte) + Optional User Data (0-4 bytes)
• Cloud Driving: Instruction Category (4 bits) + Instruction (12 bits) + Optional User Data (0-4 bytes)
• Short Message: Hello (5 bytes), how are doing (13 bytes), … (usually small, often up to 40 bytes in a short text)
mMTC Requirements: 5G: 1 million devices per square km => B5G/6G: 10 million devices per square km
Backhaul Bandwidth Efficiency: Huge IP/MPLS backhaul transport overhead so that over 80%, and even 90% bandwidth could be wasted

5. Page 5
The current IPv4/v6 solution simply can’t fully support uRLLC and RTBC
Latency (ms)
Packet Loss Ratio
0
100
-3
10 -4
10 -5
10 -6
10 -7
10 -8
10 -9
10 -10
10
References:
ITU-T Focus Group on Network 2030 Deliverables
3GPP TS 22.261 V15.5.0 (2018-07)
3GPP TS 22.261 V17.3.0 (2020-07)
3GPP TR 22.804 V16.2.0 (2018-12)
3GPP TS 22.104 V17.3.0 (2020-07)
better
better
50
10
1
20
Electricity
Distribution
Holographic
Teleport
Remote
Control
Tactile
Internet
Intelligent
Transport
Robots
High Voltage
Electricity
Distribution
Industrial
Automation
• Packet can be lost
• If retransmitted, the latency
is tripled
• No guarantee for precise KPI
App (user)
TCP (user)
IP (user)
GTP-U (S1)
UDP (Network)
IP (Network)
IP/MPLS/SRv6 Backhaul
Ethernet/PPP
The uRLLC KPI is mission critical and sometimes life critical for 5G/B5G services, but IPv4/IPv6 cannot guarantee KPI. We
need a way to evolve IPv4/v6 for uRLLC and RTBC

6. 6
Existing Addressing
• Most Popular L3 Addresses
– IPv4 and IPv6
• Many Others
– Location + ID Separation
• LISP (IETF RFC 6830)
– Digital Object Architecture (DOA)
• DOI (https://www.cnri.reston.va.us/activities.html)
– Service ID
• draft-jiang-service-oriented-ip-03
– ICN, NDN, CCN
• Names and/or IDs for Information and/or Content
– ID: E.g., DeviceNet ID (IEC 62026-3)
– NSAP (ISO/IEC 8348)
– Mixed Addresses
• Mixture of MAC, IP, and Naming in Profinet (IEC 61158 / IEC 61784-
1 and IEC 61784-2)
– Flexible Addressing System
• Variable-length addresses (ACM Sigcomm NEAT 2019)
1) Designed for general connectivity
2) “One size fits all”, but in reality one size may not
fit all nicely
3) Prone to address spoofing because of its well-
known global format
4) Privacy infringement and surveillance made
easier through IPv6 homogenization everywhere
5) Internet Consolidation (or Concentration)
ISOC 2019 Global Internet Report
6) Internet Ossification
Keynote Speech in ITU-T FG Network 2030 London
Meeting
7) Some proposals repurpose components of IPv6
addresses or overload their semantics
8) Address optimization and compression are being
proposed, especially for IoT, Industrial IoT
e.g. IETF WGs ROLL, 6TISCH, 6LO, etc
Analysis of IPv4 and IPv6

7. 7
As a matter of fact, for private or limited networks, we don’t have to use globally-formatted
network addresses! This is so true for industrial networks (manufacturing, gas pipeline, mining)
Source Destination Data
192.168.100.101 192.168.500.200 Hello
192.168.200.* 192.168.500.*
192.168.300.*
192.168.100.*
R1 R3
R2 R5
Industrial Network
Common Prefix: 192.168.0.0/16
192.168.100.101
192.168.500.200
A
B
Full Address in Packet from A to B
4768
330-4768
(408) 330-4768
+1 (408) 330-4768
4419
330-4419
(408) 330-4419
+1 (408) 330-4419
▪ No need to dial the full number 1 408 330 4419
▪ Dial what is needed depending on where the receiver is
P1 P2
Address
Type
Source Destination Data
Short
Address
100.101 500.200 Hello
Short Address in Packet from A to B
OSPF, ISIS
No Change
BGP
No Change
No Change
RIB
FIB
The common prefix is truncated
PLC
❖ This idea can extend to other
contexts and topologies to
form flexible variable-length
addressing systems
❖ It can be combined with mix
and match
• Wasteful
• Easier to attack
• Economical
• More Secure

8. 8
Source
Address
Destination
Address
Source
Type
Source
Address
Destination
Type
Destination
Address
User Data
User Data
❖ Free-Choice Addressing
❖ Mix and Match
▪ It provides freedom to network operators and application developers to choose the most effective addressing system for their domains
and applications.
▪ It does not dictate the use of addressing systems.
▪ When a new addressing system is introduced, there is no need to define a newer IP again - A lesson learnt from IPv6
▪ Existing addressing systems are optimized where possible, and new addressing systems are permitted where necessary.
▪ Industrial domains may customize their addressing systems. For example, If an OT network has only a few thousands of terminals, it
can use short versions of IP addresses.
▪ Compare with postal mails: The sender has a Japanese address and the receiver has an English address
▪ Mix-and-Match is powerful when converging IT networks and OT networks.
▪ Example: An IPv6 device can talk with a LISP terminal
▪ Example: An IPv4 PLC controller can talk with a Profinet Class B terminal in geographically different LANs
Address
Type
• Protection of Industrial Networks
• Energy-Efficiency for Small Devices of mMTC and HCS
• The freedom and autonomy of networks and domains
Why do we need new and more addressing schemes for private/limited networks?
• Accommodation of Connection for Unconnected Industrial Machines
• Integration of Terrestrial Networks and other Networks
What can we use as other options for addressing schemes?

9. Page 9
Now that IPv4/v6 does have some limits, what can we do about them and how?
Answer: An incremental evolution to expand the scope of its applicability for future applications and services
Header User Payload
KPI (latency, packet loss, etc)
Sender’s Intent
In-Band OAM and Telemetry
Network Programmability
IPv4/IPv6
Header Contract User Payload
Addressing Evolution Payload Evolution
Evolved Header Contract Evolved User Payload
Flexible Addressing System
Geography-Based Addressing
Integration of Satellite and Terrestrial Networks
Holographic Teleport
Holographic Type Communications
Qualitative Communications
Entropy-Based Communication
Evolution into Modern Courier-like Datagrams
References:
(1) New IP: A Data Packet Framework to Evolve the Internet, IEEE HPSR 2020, 2020
(2) New IP: Enabling the Next Wave of Networking Innovation, in Design Innovation and Network Architecture for the Future Internet: Computer Science & IT Books | IGI Global (igi-global.com)

10. 10
Thank You