Transcript 802.21_IETF_DNA_r2

March. 2004
doc.: 802.21_IETF_DNA_r1
802.21
L2 Services for Handover
Optimization
David Johnston
[email protected]
[email protected]
Submission
Slide 1
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Purpose (of these slides)
• Introduce 802.21
• Describe work relevant to DNA
• Solicit feedback
Submission
Slide 2
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
802.21
• Approved as a full IEEE WG Feb 27th
• Has been meeting as an ECSG for 1 year
• Initial charter to study handover between
– 802.x  802.x (where handover not supported)
– 802.x  802.y (where x may not equal y)
– 802.x Non 802 (e.g. cellular)
• Now has approved PAR for ‘Media
Independent Handover Services’
Submission
Slide 3
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Motivation
• Multi-Interfaced Devices
– Laptops, PDAs, 11/16/PP/PP2 handsets etc.
• Session maintenance
– Across heterogeneous media
• Inadequate L2 support for L3 DNA and
Mobopts activities.
Submission
Slide 4
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Problems We Are Addressing
• You don’t know what you attached to when
you associated/registered/plugged into a L2
network
• Upper layers don’t know what is going on at
L2 and so can’t make good handover
decisions
• There is no media independent way of
asking for handover related information
over a link. A conduit is needed.
Submission
Slide 5
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Relevant Elements in Network
L3 Network
AR
AP
802.y
AP
802.x
AP
802.x
AR
AR
AP
802.x
AP
802.y
Potential links
802.x
One or more
802 interfaces
Submission
802.y
Mobile Device
y=x | y!=x
Slide 6
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Work
• DNA
– Put in place useful L2 network detection
mechanisms
• Handover Optimization
– Handover information definition and transport
– L2 Triggers
• Other
– Cellular coupling methods
Submission
Slide 7
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
DNA Related Proposals
• CUPE (Controlled/Uncontrolled Port Entity)
–
–
–
–
Builds on 802.1X fork
Provides media independent access to ‘information’
DNA is the primary purpose of that information
Authenticity determined by which side of the fork the
information resides on
– Media specific optimizations expected (through 802.11
FR and 802.16e)
Submission
Slide 8
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
The Link Interface
• A media independent protocol operating
over 802 links
– Get handover or network detection and
selection information
– Maybe act as conduit for event into
– Maybe act as conduit for backhaul signaling
• CUPE model being promoted
– Controlled and Uncontrolled Port Entity
Submission
Slide 9
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
802.1x
Submission
MobileIP
AppleTalk
Etc..
EAPoL
LSAP
LSAP
LSAP
LSAP
LLC
LLC
MAC
MAC
PHY
PHY
Slide 10
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
CUPE* Model
*Controlled/Uncontrolled Port Model
MobileIP
LSAP
Submission
Secured
Handoff
Information
base
LSAP
EAPoL
LSAP
Non secured
Handoff
Information
base
LSAP
LLC
LLC
MAC
MAC
PHY
PHY
Slide 11
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Upper Layer Event Binding
Peer
Secured
Handoff
Information
base
Backhaul Signalling
Magic
Roaming
Auth World
MobileIP
LSAP
EAP
Secured
Handoff
Information
base
LSAP
EAPoL
LSAP
LLC
Submission
AAA
Non secured
Handoff
Information
base
LSAP
LLC
Slide 12
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Handover Information
• Define Information semantics
–
–
–
–
–
Am I likely to authenticate here?
Subnet crossing indicators
What is the L3 service (IP, AT, ATM, etc)?
Neighborhood lists
Vendor
• Define Encoding
• Define Transport
Submission
Slide 13
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Handover Information Equivalence
• The utility of any information increases with its
similarity in terms of structure and semantics to
information in other network domains
– Try to align with structured information from non 802
groups to allow effective interworking with them
• IETF, 3GPP, 3GPP2
– Achieve levels of mapping
• Structure equivalence – easy
• Semantic equivalence – requires hard work
• Encoding equivalence – next to impossible
Submission
Slide 14
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Backhaul DNA
• My current link is better at delivering data
to me than my pre-association/pre-initialranging link to the AP/BS over there
• Ask for the information via the local AP/BS
who fetches it from the candidate AP/BS
• Some level of protocol required to do this
and L3 support to render media
independence
Submission
Slide 15
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
The Service
MAC
PHY_SAP
PHY
Submission
MLME
MLME_SAP
MAC_SAP
Slide 16
PLME
SME
Messages are generic, E.G.:
Link_up
Link_down
Link_event_pre_indication(what,when)
Handoff_request(where, why)
Fetch_base_descriptor(from where)
MAC and PHY implementations determin
mapping to these based on their own
special cases
Pass triggers and/or roaming
decision data through management
interface?
PLME_SAP
MAC_SAP Messages
Defined within base MAC
Spec (802.3/11/16)
+
MAC_SAP Messages
Defined within HO Spec
802.x[.y]
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Define L1,2 – L3 Triggers
• This is the primary driver for the group
– To maintain L3 sessions during handoff L2 support is
required eg. TRIGTRAN, SEAMOBY, MOBOPTS
– Triggers are the underlying mechanism for enabling
seamless handoffs where possible
– Triggers can be generic (link_up, link_down, etc)
• It is the responsibility of an implementation to determine why
and when it would fire a trigger.
• Enables proprietary differentiation in lower layer mechanisms
while maintaining a standard interface
– Could be extensible. Vendor proprietary triggers?
• Will talk about this further in mobopts
Submission
Slide 17
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Feedback?
• We need this stuff to match well to the needs of
mobopts and DNA, otherwise we are wasting our
time.
– Approval at the 802.21 to iterate trigger and DNA
proposals with the IETF to achieve a stable spec
?
Submission
Slide 18
David Johnston, Intel
March. 2004
doc.: 802.21_IETF_DNA_r1
Where to Look
• http://www.ieee802.org/handoff
– Details for the mailing list are there
• Its open to all
Submission
Slide 19
David Johnston, Intel