IPv6 Multicast Address Space

Last Updated

2026-04-07

Expert(s)

Stig Venaas

Note

IPv6 multicast addresses are defined in "IP Version 6 Addressing
Architecture" [RFC 4291]. This defines fixed scope and variable scope
multicast addresses.

IPv6 multicast addresses are distinguished from unicast addresses by the
value of the high-order octet of the addresses: a value of 0xFF (binary
11111111) identifies an address as a multicast address; any other value
identifies an address as a unicast address.

The rules for assigning new IPv6 multicast addresses are defined in
[RFC 3307].  IPv6 multicast addresses not listed below are reserved.
  

Formerly known as

IPv6 Multicast Address Space Registry

Available Formats

XML
HTML
TXT

Registries Included Below

• IPv6 Multicast Address Scopes
• Node-Local Scope Multicast Addresses
• Link-Local Scope Multicast Addresses
• Site-Local Scope Multicast Addresses
• Variable Scope Multicast Addresses
• Unicast-based (Including SSM) Multicast Group IDs
• Dynamic Multicast Group IDs

IPv6 Multicast Address Scopes

Registration Procedure(s)

IETF Review

Reference

[RFC 7346]

Note

The definition of any Realm-Local scope for a particular network
technology should be published in an RFC.  For example, such a
scope definition would be appropriate for publication in an
'IPv6-over-foo' RFC.

Any RFCs that define a Realm-Local scope will be listed in this
registry as an additional reference in the Realm-Local scope
entry.  Such RFCs are expected to make an explicit request to
IANA for inclusion in this registry.
    

Available Formats

CSV

Node-Local Scope Multicast Addresses

Registration Procedure(s)

Expert Review

Reference

[RFC 4291][RFC 3307]

Note

These permanently assigned multicast addresses are valid over a specified
scope value.
    

Request an Assignment

[https://www.iana.org/protocols/apply]
    
    

Available Formats

CSV

Link-Local Scope Multicast Addresses

Registration Procedure(s)

Expert Review

Reference

[RFC 3307]

Note

These permanently assigned multicast addresses are valid over a specified
scope value.
    

Request an Assignment

[https://www.iana.org/protocols/apply]
          
    

Available Formats

CSV

Site-Local Scope Multicast Addresses

Registration Procedure(s)

Expert Review

Reference

[RFC 3307]

Note

These permanently assigned multicast addresses are valid over a specified
scope value.
    

Request an Assignment

[https://www.iana.org/protocols/apply]
          
    

Available Formats

CSV

Variable Scope Multicast Addresses

Registration Procedure(s)

Expert Review

Reference

[RFC 3307]

Note

These permanently assigned multicast addresses are valid over all scope
ranges.  This is shown by an "X" in the scope field of the address that
means any legal scope value.

As defined in [RFC 4291], IPv6 multicast addresses which are only different
in scope represent different groups.  Nodes must join each group individually.
    

Request an Assignment

[https://www.iana.org/protocols/apply]
          
    

Available Formats

CSV

Unicast-based (Including SSM) Multicast Group IDs

Registration Procedure(s)

Addresses in FF3X:0::/32 but not listed below are reserved for future SSM
address use, but are currently invalid.
FF3X:0:0:0:0:0:0:0-FF3X:0:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF (FF3X:0::/32)

FF3X:0:0:0:0:0:4000:0-FF3X:0:0:0:0:0:7FFF:FFFF - Expert Review; see registry 
at [https://www.iana.org/assignments/perm-mcast-groupids]

FF3X:0:0:0:0:0:8000:0-FF3X:0:0:0:0:0:FFFF:FFFF - Uses dynamic assignment 
according to the protocols listed in the [Dynamic Multicast Group IDs] 
registry [RFC 10028]
    

Reference

[RFC 3307]

Available Formats

CSV

Dynamic Multicast Group IDs

Reference

[RFC 3307][RFC 10028]

Available Formats

CSV

Contact Information