Ad hoc Network Autoconfiguration WG (autoconf)
Tuesday, November 8, 2005 at 1740-1840
CHAIRS: Shubhranshu Singh
Minute taker: Masafumi Watari
- Agenda bashing :05 min
- AUTOCONF charter presentation: 10 min
- MANET architecture discussion - Chairs: 20 min
- Terminology & Problem statement discussion - Perkins:
(draft-singh-autoconf-adp-02.txt) : 15 min
- Framework for MANET autoconfiguration - Mase: 10 min
- (multi-gateway considerations, if time permits - Simon Ruffino )
AUTOCONF charter presentation - Chairs
Changes since autoconf BOF
Tom: Whether also IPv4 autoconfiguration be part of this or is it
Thomas: IPv6 only and is chartered.
Tom: Know a few people interested in it. Would the WG consider
Margarret: No. If we finish IPv6, then we can consider that.
- MANET Architecture discussion - Chairs: 20 min
- Chartering process of AUtoCONF revealed divergent understanding: "we
know, but havnen't communicated well"
- MANET originated in routing area
- Now spreading to INT area
- Deployment scenarios, which may, in time, involve other WGs and areas
- Since ATOCONF brought the need of such discussion & document to light:
-> first deliverable of AUTOCONF
- What is a MANET?
- Why is it different/
- What does MANET imply for IP / the IETF?
- Overriding question:
- Do we need to rework all IETF protocols inorder to function MANET?
- MANETs support:
- highly dynamic topology
- fragile, low-capacity links
- no dedicated infrastructure components
Other Networks |MANETs
Links for the network |Network forms the links
Broadcast Interfaces |Half-Broadast Interfaces
Routing: diff. interfaces |Routing: same interface
Hierarichal ctrl. structure |Entirely "flat", decentralized
Seperate infra./host |Both infra./host
No, or macro-mobility |Yes - micro mobility
Q: When you talk about Hierarichal, are you refering to the control
Thomas C: Yes
Dave T: Routing in diff/same, I don't see a real difference.
Thomas: The difference is with Broadcast and multicast.
Dave T: Then your talking about the second line, so there is no difference
with the third line. On the 4th one, there are work on it so
Dave T: Is it true that it is not legal for a node not to have to forward
in the base requirement?
Charlie: Entirely "flat"... issue.
Q: with the routing, there might be cases re-directs.
Marshley: Does a MANET node has to forward?
Marshley: Then it is not entirely flat.
Thomas C: MANET protocol is flat, there could be hierarichal topology
with other protocols.
Q: About routing in the same interface issue, I want to generaize that
when MANET nodes could have multiple interfaces. Whether there is a need
to relay or not, MANET node must do so. How would we call MANET nodes
that does not involved in relaying. We need to clarify that.
Thomas C: We will discuss this on the ML.
- This IETF
- Solicit disussions on arch I-D
- Post IETF
- publish MANET arch I-D
- Oct 05: submit "MANET arch" document for WG review
- Apr 06: submit "MANET architecture" document to IESG for publication
Dave T: I think that it is a right place to do this here in the INT area.
Terminology & Problem statement discussion - C. Perkins:
Updates since ver 00
- A better term explanation
- Problem Statement section
- MANET node's multi-hop feature explanation
- MANET node's host and router capability explanation
- Inclusion of goals section
- Better scenario section explanation
- Editorial changes
- Local address
- valid only within the MANET
- Standalone ad hoc netwokr
- MANET not connected to any other/infra network
- Hybrid ad hoc network
- MANET connected to infra network
- Internet Gateway
- a node which has connectivity to the internet and enables a MANET
to be reachable from the Internet
- Sometimes called GATEWAY for short
RM: Local address, to me don't have clear picture in a Hierarichal MANET.
So, MANET is considered as a stub network, if we have large MANETs, and
dive MANET into MANET, then what is the scope for the local address?
Charlie: It seems to me that would be outside of the initial scope of
the charter. It could be possible by extending the first effort.
RM: How would you define the scope of the local address?
Charlie: For example by changing the prefix length?
Dave T: MANET node may have nodes that are not forwarders, so does local
address include nodes that doesn't do forwarding. Unique local address
would be more preferrable.
Charlie: Are you suggesting not to include the term?
Dave T: We should not try and invent new terms.
Thomas C: Agree on that.
- Duplicate address detection
- Network Merger
- Network partition
- Typical features of ad hoc networks
- Multi-hop packet forwarding
- Hosts also relay packets
- Arbitrary mobility/dyanmic topology
- Different concept of link
- These features require reexaminaiton of existing mechanisms
- RFC 2462, 2461, 3315, etc
- No standard specification today describes how ad hoc nodes should
autoconfigure an IP address and perform DAD
Problem Statement (scenarios)
- A MANET may appear in two different situations
- There is complete absence of any infra
- standalone ad hoc network
- there is address and/or prefix allocation agency
- hybrid ad hoc network
- switching between the above wo
- requires the allocation modes to be compabitle
- A MANET autoconfiguration solution should be able to accomomodate all
Problem Statement (partition/merger)
- Network merger & partition
- inherent property of ad hoc network
- may occur at any point of time
- merger may result i naddress conflict
- relevant to standalone as well as hybrid network
- partition may not cause any problem, but resources could be used
multiple times after the partition ocurs (i.e., once in each partitioned
RM: If you have a MANET with two gateways and advertise same prefixes,
do you have to host route and share to the gateways? Parition case could
be a problem with multiple gateway.
Charlie: Agree for further studies.
Thomas N: Its not specific to MANET and can also be said to any network
Charlie: Not different but enphasize the need for a solution to the problem
- A MANET node which needs to configure an address
- MUST configure local address(es) when standalone. It MAY also configure global
address(es) when connected to the Internet.
- MUST perform duplicate address detection
- SHOULD use a mechanism to detect network merger and to ensure the uniqueness of its current address-in-use
- MAY need a mechanism to detect network partition
- Note regarding security:
Q: DAD before interface thing, you may need to join a routing protocol,
that seems hard to meet.
Charlie: There are several ways to do it and there is a solution, but is
not the only solution.
RM: Should we require to mention to the goals in the solution.
Charlie: lets take it to the ML.
- MANET-DAD ro DAD?
- MANET-local address or local addres
- Any others
- Routing-addressing dependincies
- security considerations
Brain: Back in the goals, do you have a number of nodes...
Thomas N: DAD, you need to work it across the entire MANET, but the
thing you need is DAD that local in each MANET. For example, if we can
have only a single node for each link, then what we need is a mechanism
to provide unique prefix to each link
Thomas: Will continue discussion on that on the ML.
- Framework for MANET autoconfiguration - Mase: 10 min
A Common Framework for Autoconfiguration of Stand-Slone Ad Hoc Networks
- Autoconfiguration of unique local address for a stand-alone MANET
- Not a solution, but a common framework
- Tentative address
- Address generation
- MANET-wide DAD
- The action of detecting address conflict in the MANET
- Pre-Service MANET-DAD: verify that a tentative address is out of address
conflict with other MANET nodes.
- In-Service MANET-DAD
- Familiar addres - an address is familiar to a node
Out of time....skipping slides
Fig: Autoconfiguration state transition diagram.
Additional Benefits of Autoconfiguration States
Thomas C: While we have two charter items on the architectural and
problem statements, that does not preclude that on the ML in producing
the solution space. Also please get involved in the architectural