�IPv6 Mostly Networks
Alejandro Acosta
@ITandNetworking
IPv6 Only - The new Internet landscape
[1] Image from: https://sp.depositphotos.com/226297898/stock-photo-graphic-human-evolution-detail-history.html
IPv4 Only
IPv6 Only
A little IPv6
Dual Stack
v4 - v6 Proxies & ALG
IPv6 Mostly Networks
IPv6 Mostly networks (RFC 8925) are a relatively new concept with a rapidly growing adoption rate. They bridge the gap between IPv6-only networks and dual-stack networks. Their application aims to conserve IPv4 addresses in networks where both IPv6 families are available.
Made by por Bing AI
Technical concept
RFC 8925 in section 1.2 defines:
A network that provides NAT64 (possibly with DNS64) service as well as IPv4 connectivity and allows the coexistence of IPv6-only, dual-stack, and IPv4-only hosts on the same segment. Such a deployment scenario allows operators to incrementally turn off IPv4 on end hosts, while still providing IPv4 to devices that require IPv4 to operate. But IPv6-only-capable devices need not be assigned IPv4 addresses.
Technical concept
RFC 8925 in section 1.2 defines:
A network that provides NAT64 (possibly with DNS64) service as well as IPv4 connectivity and allows the coexistence of IPv6-only, dual-stack, and IPv4-only hosts on the same segment. Such a deployment scenario allows operators to incrementally turn off IPv4 on end hosts, while still providing IPv4 to devices that require IPv4 to operate. But IPv6-only-capable devices need not be assigned IPv4 addresses.
Technical concept
RFC 8925 in section 1.2 defines:
A network that provides NAT64 (possibly with DNS64) service as well as IPv4 connectivity and allows the coexistence of IPv6-only, dual-stack, and IPv4-only hosts on the same segment. Such a deployment scenario allows operators to incrementally turn off IPv4 on end hosts, while still providing IPv4 to devices that require IPv4 to operate. But IPv6-only-capable devices need not be assigned IPv4 addresses.
Technical concept
RFC 8925 in section 1.2 defines:
A network that provides NAT64 (possibly with DNS64) service as well as IPv4 connectivity and allows the coexistence of IPv6-only, dual-stack, and IPv4-only hosts on the same segment. Such a deployment scenario allows operators to incrementally turn off IPv4 on end hosts, while still providing IPv4 to devices that require IPv4 to operate. But IPv6-only-capable devices need not be assigned IPv4 addresses.
Technical concept
RFC 8925 in section 1.2 defines:
A network that provides NAT64 (possibly with DNS64) service as well as IPv4 connectivity and allows the coexistence of IPv6-only, dual-stack, and IPv4-only hosts on the same segment. Such a deployment scenario allows operators to incrementally turn off IPv4 on end hosts, while still providing IPv4 to devices that require IPv4 to operate. But IPv6-only-capable devices need not be assigned IPv4 addresses.
Before we continue, let's review the DHCP process in IPv4.
Practical example of DORA
After the Acknowledge the resource is not available for N seconds
Very briefly: DHCP options
DHCP options are additional configuration parameters that a DHCP client and/or server share to configure different network parameters (signaling).
Source: Google Gemini
RFC 8925 – What’s the deal with IPv6 Mostly
IPv6-Only Preferred Option for DHCPv4
Fuente: Google Gemini
This document specifies a DHCPv4 option to indicate that a host supports an IPv6-only mode and is willing to forgo obtaining an IPv4 address if the network provides IPv6 connectivity
A new DHCP Option appears
Using DHCPv4 to turn off IPv4
Baed on Ondrej Caletka presentation
�
R
DISCOVER
Parameters requested: GW, DNS…, 108
IPv4 netmask, GW, DNS, …, 108: 30 minutes
OFFER
DHCP server is
Configured to
Prefer IPv6-only
operation
DHCP client aborts
The transaction and
waits 30 minutes
Client
Server
Using DHCPv4 to turn off IPv4
Baed on Ondrej Caletka presentation
�
R
DISCOVER
Parameters requested: GW, DNS…, 108
IPv4 netmask, GW, DNS, …, 108: 30 minutes
OFFER
DHCP server is
Configured to
Prefer IPv6-only
operation
DHCP client aborts
The transaction and
waits 30 minutes
Client
Server
NEVER REACHES ACKNOWLEDGE PHASE AND THE RESOURCE IS NOT BLOCKED/RESERVED AND STILL AVAILABLE
�
Comparison of DHCPv4 negotiation
With 108 option
No 108 option
Configuration and capture examples
Server side configuration
Capture in Wireshark
In summary: How to get to IPv6-Mostly?
Mandatory
Optional
Advantages of an IPv6 Network
Questions? / Inquiries / Complaints