The Link-Local Multicast Name Resolution (LLMNR) is a protocol based on the Domain Name System (DNS) packet format that allows both IPv4 and IPv6 hosts to perform name resolution for hosts on the same local link. It is included in Windows Vista, Windows Server 2008, Windows 7, Windows 8, Windows 10.[1] It is also implemented by systemd-resolved on Linux.[2] LLMNR is defined in RFC 4795 but was not adopted as an IETF standard.[3]
As of April 2022, Microsoft has begun the process of phasing out both LLMNR and NetBIOS name resolution in favour of mDNS.[4]
IPv6 - FF02:0:0:0:0:0:1:3 (this notation can be abbreviated as FF02::1:3), MAC address 33-33-00-01-00-03
The responders also listen on TCP port 5355 on the unicast address that the host uses to respond to queries.
Packet header structureedit
Bit offset
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
0
ID
16
QR
Opcode
C
TC
T
Z
Z
Z
Z
RCODE
32
QDCOUNT
48
ANCOUNT
64
NSCOUNT
80
ARCOUNT
ID - A 16-bit identifier assigned by the program that generates any kind of query.
QR - Query/Response.
OPCODE - A 4-bit field that specifies the kind of query in this message. This value is set by the originator of a query and copied into the response. This specification defines the behavior of standard queries and responses (opcode value of zero). Future specifications may define the use of other opcodes with LLMNR.
C - Conflict.
TC - TrunCation.
T - Tentative.
Z - Reserved for future use.
RCODE - Response code.
QDCOUNT - An unsigned 16-bit integer specifying the number of entries in the question section.
ANCOUNT - An unsigned 16-bit integer specifying the number of resource records in the answer section.
NSCOUNT - An unsigned 16-bit integer specifying the number of name server resource records in the authority records section.
ARCOUNT - An unsigned 16-bit integer specifying the number of resource records in the additional records section.
^Mikael Eiman (2015-05-25). "LLMNR, Multicast DNS and names on your LAN". Retrieved 2021-01-30.
^Aligning on mDNS: ramping down NetBIOS name resolution and LLMNR
External linksedit
Link-Local Multicast Name Resolution, Microsoft TechNet
RFC 4795, Informational, Link-Local Multicast Name Resolution (LLMNR)
LLMNR, Multicast DNS and names on your LAN
January 01, 1970
link, local, multicast, name, resolution, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, news, newspapers, books, s. This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Link Local Multicast Name Resolution news newspapers books scholar JSTOR September 2018 Learn how and when to remove this message The Link Local Multicast Name Resolution LLMNR is a protocol based on the Domain Name System DNS packet format that allows both IPv4 and IPv6 hosts to perform name resolution for hosts on the same local link It is included in Windows Vista Windows Server 2008 Windows 7 Windows 8 Windows 10 1 It is also implemented by systemd resolved on Linux 2 LLMNR is defined in RFC 4795 but was not adopted as an IETF standard 3 As of April 2022 Microsoft has begun the process of phasing out both LLMNR and NetBIOS name resolution in favour of mDNS 4 Contents 1 Protocol details 2 Packet header structure 3 See also 4 References 5 External linksProtocol details editIn responding to queries responders listen on UDP port 5355 on the following link scope Multicast address IPv4 224 0 0 252 MAC address 01 00 5E 00 00 FC IPv6 FF02 0 0 0 0 0 1 3 this notation can be abbreviated as FF02 1 3 MAC address 33 33 00 01 00 03 The responders also listen on TCP port 5355 on the unicast address that the host uses to respond to queries Packet header structure editBit offset 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 ID 16 QR Opcode C TC T Z Z Z Z RCODE 32 QDCOUNT 48 ANCOUNT 64 NSCOUNT 80 ARCOUNT ID A 16 bit identifier assigned by the program that generates any kind of query QR Query Response OPCODE A 4 bit field that specifies the kind of query in this message This value is set by the originator of a query and copied into the response This specification defines the behavior of standard queries and responses opcode value of zero Future specifications may define the use of other opcodes with LLMNR C Conflict TC TrunCation T Tentative Z Reserved for future use RCODE Response code QDCOUNT An unsigned 16 bit integer specifying the number of entries in the question section ANCOUNT An unsigned 16 bit integer specifying the number of resource records in the answer section NSCOUNT An unsigned 16 bit integer specifying the number of name server resource records in the authority records section ARCOUNT An unsigned 16 bit integer specifying the number of resource records in the additional records section See also editNetwork Basic Input Output System NetBIOS Peer Name Resolution Protocol PNRP Multicast DNS mDNS Zero configuration networking Zeroconf References edit LLMNR The Cable Guy systemd 216 available Retrieved 2015 08 10 Mikael Eiman 2015 05 25 LLMNR Multicast DNS and names on your LAN Retrieved 2021 01 30 Aligning on mDNS ramping down NetBIOS name resolution and LLMNRExternal links editLink Local Multicast Name Resolution Microsoft TechNet RFC 4795 Informational Link Local Multicast Name Resolution LLMNR LLMNR Multicast DNS and names on your LAN Retrieved from https en wikipedia org w index php title Link Local Multicast Name Resolution amp oldid 1209509490, wikipedia, wiki, book, books, library,
