Internet DRAFT - draft-ietf-6man-lineid
draft-ietf-6man-lineid
6man Working Group S. Krishnan
Internet-Draft A. Kavanagh
Intended status: Standards Track B. Varga
Expires: February 18, 2013 Ericsson
S. Ooghe
Alcatel-Lucent
E. Nordmark
Cisco
August 17, 2012
The Line Identification Destination Option
draft-ietf-6man-lineid-08
Abstract
In Ethernet based aggregation networks, several subscriber premises
may be logically connected to the same interface of an edge router.
This document proposes a method for the edge router to identify the
subscriber premises using the contents of the received Router
Solicitation messages. The applicability is limited to broadband
network deployment scenarios where multiple user ports are mapped to
the same virtual interface on the edge router.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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 inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 18, 2013.
Copyright Notice
Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
Krishnan, et al. Expires February 18, 2013 [Page 1]
Internet-Draft Line ID Destination Option August 2012
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Conventions used in this document . . . . . . . . . . . . 5
2. Applicability Statement . . . . . . . . . . . . . . . . . . . 6
3. Issues with identifying the subscriber premises in an N:1
VLAN model . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Basic operation . . . . . . . . . . . . . . . . . . . . . . . 7
5. AN Behavior . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.1. On initialization . . . . . . . . . . . . . . . . . . . . 8
5.2. On receiving a Router Solicitation from the end-device . . 8
5.3. On receiving a Router Advertisement from the Edge
Router . . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.3.1. Identifying tunneled Router Advertisements . . . . . . 9
5.4. On detecting a subscriber circuit coming up . . . . . . . 9
5.5. On detecting Edge Router failure . . . . . . . . . . . . . 9
5.6. RS Retransmission algorithm . . . . . . . . . . . . . . . 10
6. Edge Router Behavior . . . . . . . . . . . . . . . . . . . . . 10
6.1. On receiving a Tunneled Router Solicitation from the AN . 10
6.2. On sending a Router Advertisement towards the
end-device . . . . . . . . . . . . . . . . . . . . . . . . 10
6.3. Sending periodic unsolicited Router Advertisements
towards the end-device . . . . . . . . . . . . . . . . . . 11
7. Line Identification Destination Option (LIO) . . . . . . . . . 11
7.1. Encoding of Line ID . . . . . . . . . . . . . . . . . . . 12
8. Garbage collection of unused prefixes . . . . . . . . . . . . 13
9. Interactions with Secure Neighbor Discovery . . . . . . . . . 14
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 14
11. Security Considerations . . . . . . . . . . . . . . . . . . . 14
12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 15
13.1. Normative References . . . . . . . . . . . . . . . . . . . 15
13.2. Informative References . . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
Krishnan, et al. Expires February 18, 2013 [Page 2]
Internet-Draft Line ID Destination Option August 2012
1. Introduction
Digital Subscriber Line (DSL) is a widely deployed access technology
for Broadband Access for Next Generation Networks. While traditional
DSL access networks were Point-to-Point Protocol (PPP) [RFC1661]
based, some networks are migrating from the traditional PPP access
model into a pure IP-based Ethernet aggregated access environment.
Architectural and topological models of an Ethernet aggregation
network in the context of DSL aggregation are described in [TR101].
+----+ +----+ +----------+
|Host|---| RG |----| |
+----+ +----+ | |
| AN |\
+----+ +----+ | | \
|Host|---| RG |----| | \
+----+ +----+ +----------+ \ +----------+
\ | |
+-------------+ | |
| Aggregation | | Edge |
| Network |-------| Router |
+-------------+ | |
/ | |
+----------+ / +----------+
| | /
+----+ +----+ | | /
|Host|---| RG |----| AN |/
+----+ +----+ | |
| |
+----------+
Figure 1: Broadband Forum Network Architecture
One of the Ethernet and Gigabit Passive Optical Network (GPON)
aggregation models specified in this document bridges sessions from
multiple user ports behind a DSL Access Node (AN), also referred to
as a Digital subscriber line access multiplexer (DSLAM), into a
single VLAN in the aggregation network. This is called the N:1 VLAN
allocation model.
Krishnan, et al. Expires February 18, 2013 [Page 3]
Internet-Draft Line ID Destination Option August 2012
+----------+
| |
| |
| AN |\
| | \
| | \ VLANx
+----------+ \ +----------+
\ | |
+-------------+ | |
| Aggregation | VLANx | Edge |
| Network |-------| Router |
+-------------+ | |
/ | |
+----------+ / +----------+
| | / VLANx
| | /
| AN |/
| |
| |
+----------+
Figure 2: n:1 VLAN model
1.1. Terminology
1:1 VLAN It is a broadband network deployment
scenario where each user port is mapped to
a different VLAN on the Edge Router. The
uniqueness of the mapping is maintained in
the Access Node and across the Aggregation
Network.
N:1 VLAN It is a broadband network deployment
scenario where multiple user ports are
mapped to the same VLAN on the Edge Router.
The user ports may be located in the same
or different Access Nodes.
GPON Gigabit-capable Passive Optical Network is
an optical access network that has been
introduced into the Broadband Forum
architecture in [TR156]
AN A DSL or a GPON Access Node. The Access
Node terminates the physical layer (e.g.
DSL termination function or GPON
termination function), may physically
aggregate other nodes implementing such
functionality, or may perform both
functions at the same time. This node
contains at least one standard Ethernet
Krishnan, et al. Expires February 18, 2013 [Page 4]
Internet-Draft Line ID Destination Option August 2012
interface that serves as its "northbound"
interface into which it aggregates traffic
from several user ports or Ethernet-based
"southbound" interfaces. It does not
implement an IPv6 stack but performs some
limited inspection/modification of IPv6
packets. The IPv6 functions required on
the Access Node are described in Section 5
of [TR177].
Aggregation Network The part of the network stretching from the
Access Nodes to the Edge Router. In the
context of this document the aggregation
network is considered to be Ethernet based,
providing standard Ethernet interfaces at
the edges, for connecting the Access Nodes
and Broadband Network. It is comprised of
ethernet switches that provide very limited
IP functionality (e.g. IGMP snooping, MLD
snooping etc.).
RG A residential gateway device. It can be a
Layer 3 (routed) device or a Layer 2
(bridged) device. The residential gateway
for Broadband Forum networks is defined in
[TR124]
Edge Router The Edge Router, also known as the
Broadband Network Gateway (BNG) is the
first IPv6 hop for the user. In the cases
where the Residential Gateway (RG) is
bridged, the BNG acts as the default router
for the hosts behind the RG. In cases
where the RG is routed, the BNG acts as the
default router for the RG itself. This
node implements IPv6 router functionality.
Host A node that implements IPv6 host
functionality.
End-device A node that sends Router Solicitations and
processes received Router Advertisements.
When a Layer 3 RG is used it is considered
an end-device in the context of this
document. When a Layer 2 RG is used, the
host behind the RG is considered to be an
end-device in the context of this document.
1.2. Conventions used in this document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL","SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
Krishnan, et al. Expires February 18, 2013 [Page 5]
Internet-Draft Line ID Destination Option August 2012
2. Applicability Statement
The line identification destination option is intended to be used
only for the N:1 VLAN deployment model. For the other VLAN
deployment models, line identification can be achieved differently.
The mechanism described in the document is useful for allowing the
connection of hosts that only support IPv6 stateless address auto-
configuration to attach to networks that use the N:1 VLAN deployment
model.
When the Dynamic Host Configuration Protocol (DHCP) [RFC3315] is used
for IPv6 address assignment it has the side-effect of including
reliability initiated by the end-device (the end-device retransmits
DHCP messages until it receives a response), as well as a way to
detect when the end-device is not active for an extended period of
time (the end-device would not renew its DHCP lease). The IPv6
Stateless address autoconfiguration protocol [RFC4862] was not
designed to satisfy such requirements [RSDA]. While this option
improves the reliability of operation in deployments that use Router
Solicitations rather than DHCP, there are some limitations as
specified below.
The mechanism described in this document deals with the loss of
subscriber-originated Router Solicitations (RSes) by initiating RSes
at the AN, which improves the robustness over solely relying on the
end-device's few initial retransmissions of RSes.
But the AN retransmissions imply that some information (e.g. the
subscriber's MAC address) that was obtained by the edge router from
subscriber-originated RSes may no longer be available. e.g. Since
there is no L2 frame received from the subscriber in case of an RS
sent by an AN, the L2 address information of the end-device cannot be
determined. One piece of L2 address information currently used in
some Broadband networks is the MAC address. For this reason, the
solution described in this document is NOT RECOMMENDED for networks
that require the MAC address of the endpoint for identification.
There is no indication when a subscriber is no longer active. Thus
this protocol can not be used to automatically reclaim resources,
such as prefixes, that are associated with an active subscriber. See
Section 8. Thus this protocol is NOT RECOMMENDED for networks that
require automatic notification when a subscriber is no longer active.
This mechanism by itself provides no protection against the loss of
RS induced state in access routers that would lead to loss of IPv6
connectivity for end-devices. Given that regular IPv6 hosts do not
have RS retransmission behavior that would allow automatic recovery
from such a failure, this mechanism SHOULD only be used in
Krishnan, et al. Expires February 18, 2013 [Page 6]
Internet-Draft Line ID Destination Option August 2012
deployments employing N:1 VLANs.
3. Issues with identifying the subscriber premises in an N:1 VLAN model
In a DSL or GPON based fixed Broadband Network, IPv6 end-devices are
connected to an AN. These end-devices today will typically send a
Router Solicitation Message to the Edge Router, to which the Edge
Router responds with a Router Advertisement message. The Router
Advertisement typically contains a prefix that the end-devices will
use to automatically configure an IPv6 Address. Upon sending the
Router Solicitation message the node connecting the end-device on the
access circuit, typically an AN, would forward the RS to the Edge
Router upstream over a switched network. However, in such Ethernet-
based aggregation networks, several subscriber premises may be
connected to the same interface of an edge router (e.g. on the same
VLAN). However, the edge router requires some information to
identify the end-device on the circuit. To accomplish this, the AN
needs to add line identification information to the Router
Solicitation message and forward this to the Edge Router. This is
analogous to the case where DHCP is being used, and the line
identification information is inserted by a DHCP relay agent
[RFC3315]. This document proposes a method for the edge router to
identify the subscriber premises using the contents of the received
Router Solicitation messages. Note that there might be several end-
devices that are located on the same subscriber premises.
4. Basic operation
This document uses a mechanism that tunnels Neighbor discovery
packets inside another IPv6 packet that uses a destination option
(Line ID option) to convey line identification information as
depicted in Figure 3. The use of the Line ID option in any other
IPv6 datagrams, including untunneled RS and RA messages, is not
defined by this document. The Neighbor discovery packets are left
unmodified inside the encapsulating IPv6 packet. In particular, the
Hop Limit field of the Neighbor Discovery (ND) message is not
decremented when the packet is being tunneled. This is because ND
messages whose Hop Limit is not 255 will be discarded by the receiver
of such messages, as described in Sections 6.1.1 and 6.1.2 of
[RFC4861].
Krishnan, et al. Expires February 18, 2013 [Page 7]
Internet-Draft Line ID Destination Option August 2012
+----+ +----+ +-----------+
|Host| | AN | |Edge Router|
+----+ +----+ +-----------+
| RS | |
|---------->| |
| | |
| |Tunneled RS(LIO)|
| |--------------->|
| | |
| |Tunneled RA(LIO)|
| |<---------------|
| RA | |
|<----------| |
| | |
Figure 3: Basic message flow
5. AN Behavior
5.1. On initialization
On initialization, the AN MUST join the All-BBF-Access-Nodes
multicast group on all its upstream interfaces towards the Edge
Router.
5.2. On receiving a Router Solicitation from the end-device
When an end-device sends out a Router Solicitation, it is received by
the AN. The AN identifies these messages by looking for ICMPv6
messages (IPv6 Next Header value of 58) with ICMPv6 type 133. The AN
intercepts and then tunnels the received Router Solicitation in a
newly created IPv6 datagram with the Line Identification Option
(LIO). The AN forms a new IPv6 datagram whose payload is the
received Router Solicitation message as described in [RFC2473] except
that the Hop Limit field of the Router Solicitation message MUST NOT
be decremented. If the AN has an IPv6 address, it MUST use this
address in the Source Address field of the outer IPv6 datagram.
Otherwise, the AN MUST copy the source address from the received
Router Solicitation into the Source Address field of the outer IPv6
datagram. The destination address of the outer IPv6 datagram MUST be
copied from the destination address of the tunneled RS. The AN MUST
include a destination options header between the outer IPv6 header
and the payload. It MUST insert a LIO destination option and set the
line identification field of the option to contain the circuit
identifier corresponding to the logical access loop port of the AN
from which the RS was initiated.
Krishnan, et al. Expires February 18, 2013 [Page 8]
Internet-Draft Line ID Destination Option August 2012
5.3. On receiving a Router Advertisement from the Edge Router
When the edge router sends out a tunneled Router Advertisement in
response to the RS, it is received by the AN. If there is an LIO
option present, the AN MUST use the line identification data of the
LIO option to identify the subscriber agent circuit of the AN on
which the RA should be sent. The AN MUST then remove the outer IPv6
header of this tunneled RA and multicast the inner packet (the
original RA) on this specific subscriber circuit.
5.3.1. Identifying tunneled Router Advertisements
The AN can identify tunneled RAs by installing filters based on the
destination address (All-BBF-Access-Nodes which is reserved link-
local scoped multicast address) of the outer packets, and the
presence of a destination option header with an LIO destination
option.
5.4. On detecting a subscriber circuit coming up
RSes initiated by end-devices as described in Section 5.2 may be lost
due to lack of connectivity between the AN and the end-device. To
ensure that the end-device will receive an RA, the AN needs to
trigger the sending of periodic RAs on the edge router. For this
purpose, the AN needs to inform the edge router that a subscriber
circuit has come up. Each time the AN detects that a subscriber
circuit has come up, it MUST create a Router Solicitation message as
described in Section 6.3.7 of [RFC4861]. It MUST use the unspecified
address as the source address of this RS. It MUST then tunnel this
RS towards the edge router as described in Section 5.2.
In case there are connectivity issues between the AN and the edge
router, the RSes initiated by the AN can be lost. The AN SHOULD
continue retransmitting the Router Solicitations following the
algorithm described in Section 5.6 for a given LIO until it receives
an RA for that specific LIO.
5.5. On detecting Edge Router failure
When the edge router reboots and loses state or is replaced by a new
edge router, the AN will detect it using connectivity check
mechanisms that are already in place in Broadband networks (e.g.
BFD). When such edge router failure is detected, the AN needs to
start transmitting RSes for each of its subscriber circuits that are
up as described in Section 5.4.
Krishnan, et al. Expires February 18, 2013 [Page 9]
Internet-Draft Line ID Destination Option August 2012
5.6. RS Retransmission algorithm
The AN SHOULD use the exponential backoff algorithm for retransmits
that is described in Section 14 of [RFC3315] in order to continuously
retransmit the Router Solicitations for a given LIO until a response
is received for that specific LIO. The AN SHOULD use the following
variables as input to the retransmission algorithm:
IRT 1 Second
MRT 30 Seconds
MRC 0
MRD 0
6. Edge Router Behavior
6.1. On receiving a Tunneled Router Solicitation from the AN
When the edge router receives a tunneled Router Solicitation
forwarded by the AN, it needs to check if there is an LIO destination
option present in the outer datagram. The edge router can use the
contents of the line identification field to lookup the addressing
information and policy that need to be applied to the line from which
the Router Solicitation was received. The edge router MUST then
process the inner RS message as specified in [RFC4861].
6.2. On sending a Router Advertisement towards the end-device
When the edge router sends out a Router Advertisement in response to
a tunneled RS that included an LIO option, it MUST tunnel the Router
Advertisement in a newly created IPv6 datagram with the Line
Identification Option (LIO) as described below. First, The edge
router creates the Router Advertisement message as described in
Section 6.2.3 of [RFC4861]. The edge router MUST include a Prefix
Information Option in this RA that contains the prefix that
corresponds to the received LIO (The LIO from the received tunneled
RS is usually passed on from the edge router to some form of
provisioning system that returns the prefix to be included in the RA.
It could e,g, be based on RADIUS.). Then, the Edge Router forms the
new IPv6 datagram, whose payload is the Router Advertisement message,
as described in [RFC2473] except that the Hop Limit field of the
Router Advertisement message MUST NOT be decremented. The Edge
router MUST use a link-local IPv6 address on the outgoing interface
in the Source Address field of the outer IPv6 datagram. The edge
router MUST include a destination options header between the outer
IPv6 header and the payload. It MUST insert a LIO destination option
and set the line identification field of the option to contain the
same value as that of the Line ID option in the received RS. The
Krishnan, et al. Expires February 18, 2013 [Page 10]
Internet-Draft Line ID Destination Option August 2012
IPv6 destination address of the inner RA MUST be set to the all-nodes
multicast address.
If the Source Address field of the received IPv6 datagram was not the
unspecified address, the edge router MUST copy this address into the
Destination Address field of the outer IPv6 datagram sent back
towards the AN. The link-layer destination address of the outer IPv6
datagram containing the outer IPv6 datagram MUST be resolved using
regular Neighbour Discovery procedures.
If the Source Address field of the received IPv6 datagram was the
unspecified address, the destination address of the outer IPv6
datagram MUST be set to the well-known link-local scope All-BBF-
Access-Nodes multicast address [to be allocated]. The link-layer
destination address of the tunneled RA MUST be set to the unicast
link-layer address of the AN that sent the tunneled Router
Solicitation which is being responded to.
The edge router MUST ensure that it does not transmit tunneled RAs
whose size is larger than the MTU of the link between the edge router
and the AN, which would require that the outer IPv6 datagram undergo
fragmentation. This limitation is imposed because the AN may not be
capable of handling the reassembly of such fragmented datagrams.
6.3. Sending periodic unsolicited Router Advertisements towards the
end-device
After sending a tunneled Router Advertisement as specified in
Section 6.2 in response to a received RS, the edge router MUST store
the mapping between the LIO and the prefixes contained in the Router
Advertisement. It should then initiate periodic sending of
unsolicited Router Advertisements as described in Section 6.2.3. of
[RFC4861] . The Router Advertisements MUST be created and tunneled
as described in Section 6.2. The edge router MAY stop sending Router
Advertisements if it receives a notification from the AN that the
subscriber circuit has gone down. This notification can be received
out-of-band using a mechanism such as ANCP. Please consult Section 8
for more details.
7. Line Identification Destination Option (LIO)
The Line Identification Destination Option (LIO) is a destination
option that can be included in IPv6 datagrams that tunnel Router
Solicitation and Router Advertisement messages. The use of the Line
ID option in any other IPv6 datagrams is not defined by this
document. Multiple Line Identification destination options MUST NOT
be present in the same IPv6 datagram. The LIO has no alignment
Krishnan, et al. Expires February 18, 2013 [Page 11]
Internet-Draft Line ID Destination Option August 2012
requirement.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Option Type | Option Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| LineIDLen | Line Identification...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: Line Identification Destination Option Layout
Option Type
8-bit identifier of the type of option. The option identifier
for the line identification option will be allocated by the IANA.
Option Length
8-bit unsigned integer. The length of the option (excluding
the Option Type and Option Length fields). The value MUST be
greater than 0.
LineIDLen
8-bit unsigned integer. The length of the Line Identification
field in number of octets.
Line Identification
Variable length data inserted by the AN describing the
subscriber agent circuit identifier corresponding to the logical
access loop port of the AN from which the RS was
initiated. The line identification MUST be unique across all the
ANs that share a link to the edge router. e.g. One such line
identification scheme is described in Section 3.9 of [TR101].
The line idenfication should be encoded as specified in
Section 7.1.
7.1. Encoding of Line ID
This IPv6 Destination Option is derived from an existing widely
deployed DHCPv6 Option [RFC4649], which is in turn derived from a
widely deployed DHCPv4 Option [RFC3046]. Both of those derive from
and cite the basic DHCP options specification [RFC2132]. Those
widely deployed DHCP options use the NVT character set
Krishnan, et al. Expires February 18, 2013 [Page 12]
Internet-Draft Line ID Destination Option August 2012
[RFC2132][RFC0020]. Since the data carried in the Line ID option is
used in the same manner by the provisioning systems as the DHCP
options, it is beneficial for it to maintain the same encoding as the
DHCP options.
The IPv6 Line ID option contains a description which identifies the
line, using only character positions (decimal 32 to decimal 126,
inclusive) of the US-ASCII character set [X3.4], [RFC0020].
Consistent with [RFC2132], [RFC3046] and [RFC4649], the Line ID field
SHOULD NOT contain the US-ASCII NUL character (decimal 0). However,
implementations receiving this option MUST NOT fail merely because an
ASCII NUL character is (erroneously) present in the Line ID option's
data field.
Some existing widely deployed implementations of edge routers and ANs
that support the previously mentioned DHCP option only support US-
ASCII, and strip the high-order bit from any 8-bit characters entered
by the device operator. The previously mentioned DHCP options do not
support 8-bit character sets either. Therefore, for compatibility
with the installed base and to maximise interoperability, the high-
order bit of each octet in this field MUST be set to zero by any
device inserting this option in an IPv6 packet.
Consistent with [RFC3046] and [RFC4649], this option always uses
binary comparison. Therefore, two Line IDs MUST be equal when they
match when compared byte-by-byte. Line-ID A and Line-ID B match
byte-by-byte when (1) A and B have the same number of bytes and (2)
for all byte indexes P in A: the value of A at index P has the same
binary value as the value of B at index P.
Two Line IDs MUST NOT be equal if they do not match byte-by-byte.
For example, an IPv6 Line ID option containing "f123" is not equal to
a Line ID option "F123".
Intermediate systems MUST NOT alter the contents of the Line ID.
8. Garbage collection of unused prefixes
Following the mechanism described in this document, the Broadband
network associates a prefix to a subscriber line based on the LIO.
Even when the subscriber line goes down temporarily, this prefix
stays allocated to that specific subscriber line. i.e. The prefix is
not returned to the unused pool. When a subscriber line no longer
needs a prefix, the prefix can be reclaimed by manual action
dissociating the prefix from the LIO in the backend systems.
Krishnan, et al. Expires February 18, 2013 [Page 13]
Internet-Draft Line ID Destination Option August 2012
9. Interactions with Secure Neighbor Discovery
Since the SEND [RFC3971] protected RS/RA packets are not modified in
anyway by the mechanism described in this document, there are no
issues with SEND verification.
10. Acknowledgements
The authors would like to thank Margaret Wasserman, Mark Townsley,
David Miles, John Kaippallimalil, Eric Levy-Abegnoli, Thomas Narten,
Olaf Bonness, Thomas Haag, Wojciech Dec, Brian Haberman, Ole Troan,
Hemant Singh, Jari Arkko, Joel Halpern, Bob Hinden, Ran Atkinson,
Glen Turner, Kathleen Moriarty, David Sinicrope, Dan Harkins, Stephen
Farrell, Barry Leiba, Sean Turner, Ralph Droms, and Mohammed
Boucadair for reviewing this document and suggesting changes.
11. Security Considerations
The line identification information inserted by the AN or the edge
router is not protected. This means that this option may be
modified, inserted, or deleted without being detected. In order to
ensure validity of the contents of the line identification field, the
network between the AN and the edge router needs to be trusted.
12. IANA Considerations
This document defines a new IPv6 destination option for carrying line
identification. IANA is requested to assign a new destination option
type in the Destination Options registry maintained at
http://www.iana.org/assignments/ipv6-parameters
<TBA1> Line Identification Option [RFCXXXX]
The act bits for this option need to be 10 and the chg bit needs to
be 0.
This document also requires the allocation of a well-known link-local
scope multicast address from the IPv6 Multicast Address Space
Registry located at
http://www.iana.org/assignments/ipv6-multicast-addresses/
ipv6-multicast-addresses.xml
<TBA2> All-BBF-Access-Nodes [RFCXXXX]
Krishnan, et al. Expires February 18, 2013 [Page 14]
Internet-Draft Line ID Destination Option August 2012
13. References
13.1. Normative References
[RFC1661] Simpson, W., "The Point-to-Point Protocol (PPP)", STD 51,
RFC 1661, July 1994.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2473] Conta, A. and S. Deering, "Generic Packet Tunneling in
IPv6 Specification", RFC 2473, December 1998.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3971] Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure
Neighbor Discovery (SEND)", RFC 3971, March 2005.
[RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman,
"Neighbor Discovery for IP version 6 (IPv6)", RFC 4861,
September 2007.
[RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless
Address Autoconfiguration", RFC 4862, September 2007.
[TR101] Broadband Forum, "Migration to Ethernet-based DSL
aggregation", <http://www.broadband-forum.org/technical/
download/TR-101.pdf>.
[TR124] Broadband Forum, "Functional Requirements for Broadband
Residential Gateway Devices", <http://
www.broadband-forum.org/technical/download/
TR-124_Issue-2.pdf>.
[TR156] Broadband Forum, "Using GPON Access in the context of TR-
101", <http://www.broadband-forum.org/technical/download/
TR-156.pdf>.
[TR177] Broadband Forum, "IPv6 in the context of TR-101",
<www.broadband-forum.org/technical/download/TR-177.pdf>.
[X3.4] American National Standards Institute, "American Standard
Code for Information Interchange (ASCII)", Standard X3.4 ,
1968.
Krishnan, et al. Expires February 18, 2013 [Page 15]
Internet-Draft Line ID Destination Option August 2012
13.2. Informative References
[RFC0020] Cerf, V., "ASCII format for network interchange", RFC 20,
October 1969.
[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
Extensions", RFC 2132, March 1997.
[RFC3046] Patrick, M., "DHCP Relay Agent Information Option",
RFC 3046, January 2001.
[RFC4649] Volz, B., "Dynamic Host Configuration Protocol for IPv6
(DHCPv6) Relay Agent Remote-ID Option", RFC 4649,
August 2006.
[RSDA] Dec, W., "IPv6 Router Solicitation Driven Access
Considered Harmful", draft-dec-6man-rs-access-harmful-00
(work in progress), June 2011.
Authors' Addresses
Suresh Krishnan
Ericsson
8400 Blvd Decarie
Town of Mount Royal, Quebec
Canada
Email: suresh.krishnan@ericsson.com
Alan Kavanagh
Ericsson
8400 Blvd Decarie
Town of Mount Royal, Quebec
Canada
Email: alan.kavanagh@ericsson.com
Balazs Varga
Ericsson
Konyves Kalman krt. 11. B.
1097 Budapest
Hungary
Email: balazs.a.varga@ericsson.com
Krishnan, et al. Expires February 18, 2013 [Page 16]
Internet-Draft Line ID Destination Option August 2012
Sven Ooghe
Alcatel-Lucent
Copernicuslaan 50
2018 Antwerp,
Belgium
Phone:
Email: sven.ooghe@alcatel-lucent.com
Erik Nordmark
Cisco
510 McCarthy Blvd.
Milpitas, CA, 95035
USA
Phone: +1 408 527 6625
Email: nordmark@cisco.com
Krishnan, et al. Expires February 18, 2013 [Page 17]
