Network Working Group W A Simpson
Internet Draft Daydreamer
expires in six months January 1995
IPv6 Neighbor Discovery -- ICMP Message Formats
draft-simpson-ipv6-discov-formats-02.txt
Status of this Memo
This document is a submission to the IPng Working Group of the
Internet Engineering Task Force (IETF). Comments should be submitted
to the ipng@sunroof.eng.sun.com mailing list.
Distribution of this memo is unlimited.
This document is an Internet-Draft. Internet Drafts are working
documents of the Internet Engineering Task Force (IETF), its Areas,
and its Working Groups. Note that other groups may also distribute
working documents as Internet Drafts.
Internet Drafts are draft documents valid for a maximum of six
months, and may be updated, replaced, or obsoleted by other documents
at any time. It is not appropriate to use Internet Drafts as
reference material, or to cite them other than as a ``working draft''
or ``work in progress.''
To learn the current status of any Internet-Draft, please check the
``1id-abstracts.txt'' listing contained in the internet-drafts Shadow
Directories on:
ftp.is.co.za (Africa)
nic.nordu.net (Europe)
ds.internic.net (US East Coast)
ftp.isi.edu (US West Coast)
munnari.oz.au (Pacific Rim)
Abstract
This document specifies ICMP messages for identification of and
forwarding to adjacent IPv6 nodes, including Mobility, Next Hop
Determination and Router Discovery.
Simpson expires in six months [Page i]
DRAFT IPv6 Discovery Formats January 1995
1. Additional ICMP Packets
The datagram format and basic facilities are already defined for ICMP
as modified for IPv6 [IPv6-ICMP].
Up-to-date values of the ICMP Type field are specified in the most
recent "Assigned Numbers" [RFC-1700]. This document concerns the
following values:
33 Where-Are-You Solicitations
34 I-Am-Here Advertisements
Simpson expires in six months [Page 1]
DRAFT IPv6 Discovery Formats January 1995
1.1. Where-Are-You Solicitations
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extensions ...
+-+-+-+-+-+-+-+-+-+-+-+-
Type 33
Code Up-to-date values are specified in the most recent
"Assigned Numbers" [RFC-1700]. Current values are
assigned as follows:
0 RESERVED
1 General
2 Router
3 Service (reserved)
Checksum The ICMP Checksum.
Extensions zero or more Extensions. This field is variable in
length. The Extensions SHOULD be included in the
order described. These Extensions are described in
a later chapter.
The contents of the Reserved field MUST be zero on transmission, and
MUST be ignored on receipt. Future backward-compatible changes to
the protocol may specify the contents of the Reserved field or of
additional octets at the end of the message.
Simpson expires in six months [Page 2]
DRAFT IPv6 Discovery Formats January 1995
1.1.1. General Solicitation
The General Solicitation MUST contain at least the following values:
Link Header (if any):
Destination the link equivalent of the Solicited-Nodes IPv6
Multicast Address. The mapping is described in
[IPv6-Address].
IPv6 Header:
Destination the calculated Solicited-Nodes IPv6 Multicast
Address. The scope is intra-link.
This is calculated by starting with the
exclusive-or of each byte of the target IPv6
Unicast Address, then adding the result to the
base Solicited-Nodes multicast (FF02::0700).
For example, to calculate the destination value
for target A::B:C, the exclusive-or is D. The
calculated destination would be FF02::070D.
Source any IPv6 Unicast Address associated with the
sending interface. It MUST NOT be the
Unspecified Address.
Hop Limit 1
ICMP fields:
Code 1 for General Solicitation.
Extensions:
Known-Identifier any IPv6 Unicast Address of the target. The
Prefix Size and Metric are always zero.
Maximum-Receive-Unit
for interfaces which do not have a fixed hardware
MTU.
Media-Access for interfaces which are not point-to-point
links.
Node-Heard for the target of the General Solicitation, if an
advertisement has been heard.
Simpson expires in six months [Page 3]
DRAFT IPv6 Discovery Formats January 1995
In addition, each Router Advertisement that has
been heard, in order of preference.
In the unlikely event that not all extensions fit in a single
solicitation, as constrained by the MTU of the link, the remaining
extensions are removed.
The use of the General Solicitation is described in [D-Send].
Simpson expires in six months [Page 4]
DRAFT IPv6 Discovery Formats January 1995
1.1.2. Router Solicitation
The Router Solicitation MUST contain at least the following values:
Link Header (if any):
Destination the link equivalent of the All-Routers IPv6
Multicast Address. The mapping is described in
[IPv6-Address].
IPv6 Header:
Destination the All-Routers IPv6 Multicast Address (FF02::3).
The scope is intra-link.
Source any IPv6 Unicast Address associated with the
sending interface. It MAY be the Unspecified
Address, when the node has not yet determined an
IPv6 Unicast Address.
Hop Limit 1
ICMP fields:
Code 2 for Router Solicitation.
Extensions:
Maximum-Receive-Unit
for interfaces which do not have a fixed hardware
MTU.
Media-Access for interfaces which are not point-to-point
links.
The use of the Router Solicitation is described in [D-Send].
Simpson expires in six months [Page 5]
DRAFT IPv6 Discovery Formats January 1995
1.2. I-Am-Here Advertisements
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Code | Checksum |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number | LifeTime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extensions ...
+-+-+-+-+-+-+-+-+-+-+-+-
Type 34
Code Up-to-date values are specified in the most recent
"Assigned Numbers" [RFC-1700]. Current values are
assigned as follows:
0 RESERVED
1 General
2 Router
3 Service (reserved)
4 Local Redirect
5 Remote Redirect
Checksum The ICMP Checksum.
Sequence Number the number of Advertisement messages sent since the
node was initialized. The value MUST include this
advertisement. That is, the first Advertisement
contains the value one, and the value zero indicates
that the number has rolled over.
LifeTime the time remaining before the advertised information
is considered expired, in hundredths of seconds.
The maximum time is approximately 10 minutes.
Extensions zero or more Extensions. This field is variable in
length. The Extensions SHOULD be included in the
order described. These Extensions are described in
a later chapter.
Simpson expires in six months [Page 6]
DRAFT IPv6 Discovery Formats January 1995
1.2.1. General Advertisement
The General Advertisement MUST contain at least the following values:
IPv6 Header:
Destination the Source specified in the solicitation, when
the node is not serving several neighbors, and
the node is not operating as a Mobile Node.
Otherwise, the All-Nodes IPv6 Multicast Address
(FF02::1). The scope is intra-link. These
decisions are described in [D-Send].
Source the Identifier specified in the Known-Identifier
extension of the solicitation.
Hop Limit 1
ICMP fields:
Code 1 for General Advertisement.
Lifetime the interface's configured AdvertisementLifetime.
Extensions:
Maximum-Receive-Unit
for interfaces which do not have a fixed hardware
MTU.
Media-Access for interfaces which are not point-to-point
links.
Known-Identifier for each of that node's known IPv6 Unicast
Addresses other than the IPv6 Unicast Address
specified in the IPv6 Source field. The Prefix
Size and Metric are always zero.
This supports multiple addresses per interface,
as well as multi-homed nodes. This enables the
recipient node to determine the best next-hop,
when the next-hop is on another interface
attached to the same advertising node.
Node-Heard for the sender of the General Solicitation.
In addition, each Router Advertisement that has
Simpson expires in six months [Page 7]
DRAFT IPv6 Discovery Formats January 1995
been heard, in order of preference.
In the unlikely event that not all extensions fit in a single
advertisement, as constrained by the MTU of the link, the
remaining extensions are removed.
The use of the General Advertisement is described in [D-Send].
Simpson expires in six months [Page 8]
DRAFT IPv6 Discovery Formats January 1995
1.2.2. Router Advertisement
The Router Advertisement MUST contain at least the following values:
IPv6 Header:
Destination the All-Nodes IPv6 Multicast Address (FF02::1).
The scope is intra-link.
Source the Primary Identifier of the router.
The same IPv6 Unicast Address is used for all
interfaces. When a router has more than one
interface on the same link, or a multi-homed host
can hear the same router on more than one link,
it is necessary to unambiguously know which
router sent this advertisement. The individual
routing-prefixes for the links are distinguished
in the Prefix-Information extension.
Hop Limit 1
ICMP fields:
Code 2 for Router Advertisement.
Lifetime the interface's configured AdvertisementLifetime.
Extensions:
Hop-Limit the current Internet Time-To-Live.
Maximum-Receive-Unit
for interfaces which do not have a fixed hardware
MTU.
Media-Access for interfaces which are not point-to-point
links.
Mobility-Support for interfaces which support Mobile
Registration, either as a Foreign Agent or Home
Agent [Mobility].
In the absence of this extension, all routers are
expected to support decapsulation and forwarding
from an interface, without explicit registration
by a Mobile Node.
Simpson expires in six months [Page 9]
DRAFT IPv6 Discovery Formats January 1995
Change-Identifier
for each of that interface's IPv6 Unicast or
Cluster Addresses which has changed from a value
previously advertised with the Prefix-Information
or Known-Identifier extensions. Included at
least once, and repeated until the original
LifeTime expires.
Prefix-Information
for each of that interface's associated IPv6
Unicast or Cluster Addresses whose Advertise
flags are TRUE.
Known-Identifier for each of that node's other IPv6 Unicast or
Cluster Addresses which have not already been
included through routing-prefix subsumption.
This may be another address for the same
interface, or may identify another interface on
the same node, or may proxy for another node.
When a number of interfaces, such as point-to-
point interfaces, may be aggregated with the same
routing-prefix, only one extension need be
included.
Node-Heard for each Router Advertisement that has been
heard, in order of preference.
In the unlikely event that not all extensions fit in a single
advertisement, as constrained by the MTU of the link, multiple
advertisements are sent, with each containing as many remaining
extensions as can fit.
The use of the Router Advertisement is described in [D-Send].
Simpson expires in six months [Page 10]
DRAFT IPv6 Discovery Formats January 1995
1.2.3. Local Redirect
The Local Redirect MUST contain at least the following values:
IPv6 Header:
Destination the Source specified in the datagram being
redirected.
Source the Primary Identifier of the router.
Hop Limit 1
Flow Label When the redirect applies to a single flow, this
is set to a non-zero value.
Note that this value is relative to the
Destination specified in the datagram being
redirected.
ICMP fields:
Code 4 for Local Redirect.
Sequence the last Sequence from the target node
Advertisement.
Lifetime the remaining Lifetime from the target node
Advertisement.
Extensions:
Maximum-Receive-Unit
for interfaces which do not have a fixed hardware
MTU, the Maximum-Receive-Unit extension from the
target node Advertisement.
Media-Access for interfaces which are not point-to-point
links, the Media-Access extension from the target
node Advertisement.
Known-Identifier for each IPv6 Unicast or Cluster Address
associated with the changed node(s). The Metric
is always zero.
When the redirect applies to an entire routing-
prefix, the Prefix Size is set to the size of the
routing-prefix. This enables the recipient node
Simpson expires in six months [Page 11]
DRAFT IPv6 Discovery Formats January 1995
to determine the best next-hop without multiple
redirects for each routing-prefix.
Redirected-Header
The target header.
In the unlikely event that not all extensions fit in a single
redirect, as constrained by the MTU of the link, the remaining
extensions are removed. Only a single redirect is sent.
The use of the Local Redirect is described in [D-Send].
Simpson expires in six months [Page 12]
DRAFT IPv6 Discovery Formats January 1995
1.2.4. Remote Redirect
The Remote Redirect MUST contain at least the following values:
IPv6 Header:
Destination the Source specified in the packet being
redirected.
Source the Destination specified in the packet being
redirected.
Hop Limit from the Router Advertisement.
An Authentication Header is required.
ICMP fields:
Code 5 for Remote Redirect.
Sequence the last Sequence from the target node
Advertisement.
Lifetime the remaining Lifetime from the target node
Advertisement.
Extensions:
Known-Identifier the IPv6 Unicast or Cluster Address which is
used as a Care-Of-Address to reach the Source.
Redirected-Header
The target header.
In the unlikely event that not all extensions fit in a single
redirect, as constrained by the MTU of the link, the remaining
extensions are removed. Only a single redirect is sent.
The use of the Remote Redirect is described in [D-Send].
Simpson expires in six months [Page 13]
DRAFT IPv6 Discovery Formats January 1995
2. Extensions
Extensions allow variable amounts of information to be carried within
each Solicitation or Advertisement packet. Some extensions are
common to both packet types.
The end of the list of Extensions is indicated by the Payload Length
of the IPv6 packet.
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| Extension | Length | Data ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
Extension This document concerns the following values:
0 Single Pad (no length field)
1 Multiple Pads (with length field)
2 Change-Identifier
3 Known-Identifier
4 Node-Heard
5 Prefix-Information
13 Hop-Limit
14 Maximum-Receive-Unit
15 Media-Access
16 Mobility-Support
254 Redirected-Header
Up-to-date values are specified in the most recent
"Assigned Numbers" [RFC-1700].
Length the length of the Data field. The Length does not
include the Extension and Length octets.
The Single Pad (extension 0) is a special case,
which has neither Length field nor Data field.
Data zero or more octets. The format and length of the
Data field is determined by the Extension and Length
fields.
When an extension is encountered which is not recognized, it is
ignored. The Length field is used to skip the data field in
searching for the next extension.
Every extension is aligned such that internal fields fall on natural
boundaries, except that fields larger than 64-bits need only be
aligned to 64-bit boundaries.
Simpson expires in six months [Page 14]
DRAFT IPv6 Discovery Formats January 1995
Any unused portion of the datagram between such Extensions is padded
as appropriate. The final Extension in a datagram does not require
trailing padding.
2.1. Single Pad
+-+-+-+-+-+-+-+-+
| Extension |
+-+-+-+-+-+-+-+-+
Extension 0
2.2. Multiple Pads
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
| Extension | Length | Data ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
Extension 1
Length the length of the Data field.
Data zero or more bytes of zeroes.
Simpson expires in six months [Page 15]
DRAFT IPv6 Discovery Formats January 1995
2.3. Change-Identifier
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length | 0 | Prefix Size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 2
Length 34
Prefix Size the number of bits in the Identifier which define
the routing-prefix width for the link. The value
ranges from 0 to 127.
If the Identifier does not indicate a valid prefix,
the value is zero.
Identifier an IPv6 Unicast or Cluster Address.
For usage, see the specific message description, and [D-Send].
Simpson expires in six months [Page 16]
DRAFT IPv6 Discovery Formats January 1995
2.4. Known-Identifier
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length | 0 | Prefix Size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Metric |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 3
Length 22
Prefix Size the number of bits in the Identifier which define
the routing-prefix width for the link. The value
ranges from 0 to 127.
If the Identifier does not indicate a valid prefix,
the value is zero.
Metric the preference level for use of this node to forward
packets to the Identifier. Lower values indicate
greater preference.
Identifier an IPv6 Unicast or Cluster Address.
For usage, see the specific message description, and [D-Send].
Simpson expires in six months [Page 17]
DRAFT IPv6 Discovery Formats January 1995
2.5. Node-Heard
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length | 0 | Prefix Size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sequence Number | Remaining LifeTime |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Primary Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| MRU | 0 | Speed |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Quality |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Advertisement Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Error Count |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 4
Length 38
Prefix Size the number of bits in the Primary Identifier which
define the routing-prefix width for the link. The
value ranges from 0 to 127.
If the Primary Identifier does not indicate a valid
prefix, the value is zero.
Sequence Number the last heard sequence number from the node.
Remaining LifeTime
the time remaining before the entry is considered
expired. Calculated from the LifeTime field of the
Advertisement heard.
Primary Identifier
the primary IPv6 Unicast Address for the node, taken
from the Source field of the Advertisement heard.
MRU the maximum size packet that the node will receive
over the link.
Speed the speed of the link over which the advertisement
or solicitation was heard. Higher values indicate
Simpson expires in six months [Page 18]
DRAFT IPv6 Discovery Formats January 1995
greater speed. The speed value (in bits per second)
is related to:
int( 10 * ln( speed / 100 ) )
0 link is down
1 - 9 reserved
10 300 or less
24 1,200 96 1,544,000 T1
31 2,400 99 2,048,000 E1
38 4,800 106 4,000,000 Token Ring
42 7,200 110 6,312,000 T2
45 9,600 115 10,000,000 Ethernet
49 14,400 119 16,000,000 Token Ring
52 19,200
56 28,800 130 44,736,000 T3
59 38,400 142 155,520,000 STS-3,STM-1
63 57,600 202 622,080,000 STS-12,STM-4
64 64,000 216 2,488,320,000 STS-48,STM-16
71 128,000
73 153,600
78 256,000
Quality an indication of the signal quality received from
this node. Higher values indicate greater quality.
If the Quality is not used, the value is zero.
Advertisement Count
the number of advertisements that have been heard
from the identified node.
Error Count the number of errors which have been detected on the
link with the identified node.
This extension is included in an Advertisement message to indicate a
node which has been heard.
The MRU, Speed, Quality, Advertisement Count, and Error Count are
primarily used for selecting among multiple paths in a wireless
environment.
Simpson expires in six months [Page 19]
DRAFT IPv6 Discovery Formats January 1995
2.6. Prefix-Information
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length |C|R| 0 | Prefix Size |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0 | Preference |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
~ Identifier ~
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 5
Length 18
C Contiguous. When this bit is set to 1, the
routing-prefix is entirely confined to the link.
When forwarding, a node MAY use the routing-prefix
to determine whether a target node is on the link.
R Registration. When this bit is set to 1, a node
MUST use [DHCPng] to self-configure its addresses.
Prefix Size the number of bits in the Identifier which define
the routing-prefix width for the link. The value
ranges from 0 to 127.
If the Identifier does not indicate a valid prefix,
the value is zero.
Preference the preference level for use of this node to forward
packets having a Source longest match with the
Identifier. Higher values indicate greater
preference.
Identifier one of the IPv6 Unicast or Cluster Addresses for
this interface.
This extension is found in Router Advertisements.
Simpson expires in six months [Page 20]
DRAFT IPv6 Discovery Formats January 1995
2.7. Hop-Limit
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length | Hops |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 13
Length 1
Hops the currently recommended IPv6 Hop Limit.
Up-to-date values are specified in the most recent
"Assigned Numbers" [RFC-1700].
Simpson expires in six months [Page 21]
DRAFT IPv6 Discovery Formats January 1995
2.8. Maximum-Receive-Unit
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length | MRU |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 14
Length 2
MRU the maximum size packet that the node will receive
over the link.
This extension MUST be included in those messages sent from an
interface for which there is no dependable MTU, such as Frame-Relay
or Asynchronous Transfer Mode.
Simpson expires in six months [Page 22]
DRAFT IPv6 Discovery Formats January 1995
2.9. Media-Access
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length | Family |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Media Address ...
+-+-+-+-+-+-+-+-+-+-+-+-
Extension 15
Length >= 2
Family the Address Family Number.
Up-to-date values are specified in the most recent
"Assigned Numbers" [RFC-1700].
Media Address the media address which is used to access this node.
This field is variable in length.
The Media Address is always specified in Canonical
order.
This extension MUST be included in those messages sent from an
interface on a multi-access media.
It MUST NOT be included in a message sent from a point-to-point
interface, or in messages such as the Remote Redirect which pass
through intermediate nodes.
Simpson expires in six months [Page 23]
DRAFT IPv6 Discovery Formats January 1995
2.10. Mobility-Support
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length |F| Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Extension 16
Length >= 1
F Foreign Agent bit. When this bit is set to 1,
Mobile Registration through the Foreign Agent is
required, even when the Mobile Node has acquired a
transient Care-Of-Address.
Reserved Sent as zero; ignored on reception.
This extension is found in Router Advertisements.
Simpson expires in six months [Page 24]
DRAFT IPv6 Discovery Formats January 1995
2.11. Redirected-Header
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Extension | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| IPv6 Header(s) ...
+-+-+-+-+-+-+-+-+-+-+-+-
Extension 254
Length >= 64
IPv6 Header(s) variable length, 64-bit aligned.
This extension is included in the Local or Remote Redirect to verify
the traffic that is being redirected.
Simpson expires in six months [Page 25]
DRAFT IPv6 Discovery Formats January 1995
Security Considerations
Whenever Ran gets them done.
References
[D-Send]
[DHCPng]
[IPv6-Address]
[IPv6-ICMP]
[Mobility]
[RFC-1700]
Acknowledgements
Many thanks to Fred Goldstein, K1IO (DEC, BBN) for his pioneering
work on Radio Shortest Path First (RSPF) for Amateur Packet Radio.
Thanks also for suggestions and contributions from the Simple-IP
Working Group.
Special thanks for implementation review by Alex Conta (DEC), Chuck
Desostoa (), Dan McDonald (Naval Research Laboratory), Fred Rabouw
(Network Systems Netherlands), and Brad Stone (Hewlett-Packard).
Author's Address
Questions about this memo can also be directed to:
William Allen Simpson
Daydreamer
Computer Systems Consulting Services
1384 Fontaine
Madison Heights, Michigan 48071
Bill.Simpson@um.cc.umich.edu
bsimpson@MorningStar.com
Simpson expires in six months [Page 26]
DRAFT IPv6 Discovery Formats January 1995
Simpson expires in six months [Page 27]
DRAFT IPv6 Discovery Formats January 1995
Table of Contents
1. Additional ICMP Packets ............................... 1
1.1 Where-Are-You Solicitations ..................... 2
1.1.1 General Solicitation ............................ 3
1.1.2 Router Solicitation ............................. 5
1.2 I-Am-Here Advertisements ........................ 6
1.2.1 General Advertisement ........................... 7
1.2.2 Router Advertisement ............................ 9
1.2.3 Local Redirect .................................. 11
1.2.4 Remote Redirect ................................. 13
2. Extensions ............................................ 14
2.1 Single Pad ...................................... 15
2.2 Multiple Pads ................................... 15
2.3 Change-Identifier ............................... 16
2.4 Known-Identifier ................................ 17
2.5 Node-Heard ...................................... 18
2.6 Prefix-Information .............................. 20
2.7 Hop-Limit ....................................... 21
2.8 Maximum-Receive-Unit ............................ 22
2.9 Media-Access .................................... 23
2.10 Mobility-Support ................................ 24
2.11 Redirected-Header ............................... 25
SECURITY CONSIDERATIONS ...................................... 26
REFERENCES ................................................... 26
ACKNOWLEDGEMENTS ............................................. 26
AUTHOR'S ADDRESS ............................................. 26