FIND Mobility/DTN
Sub-Group Meeting Report
At WINLAB, Rutgers University, NJ
May 29-30, 2007
Presented by: Sanjoy Paul, WINLAB, Rutgers U.
Summary
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1.5 day Meeting at WINLAB, Rutgers University, May 29-30
•
5 groups: 3 FIND projects and 2 external groups with projects in related space
F
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D
– Transient Network Architecture (TNA) -- CNRI/UNM: Henry Jerez
– Day After Network (DAN) --- UIUC: Robin Kravets
– Postcards from the Edge: A Cache and Forward Architecture – Rutgers & UMASS:
Roy Yates, Sanjoy Paul, Dipankar Raychoudhuri and Jim Kurose
– SPINDLE/DTN – BBN: Rajesh Krishnan
– Ambient Networks – EU (Ericsson): Lars Lundgren
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Goal: explore synergies, identify gaps, define a comprehensive project in the area
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Agenda:
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Summary of results to be presented at FIND meeting
•
Detailed agenda, slides, etc. posted at:
– 20-30 min talk from each of the 5 groups
– Look for Similarities and Synergies
– Use of GENI: What kind of experimental facility (say in GENI) be most valuable to
instantiate the specific research project
– Identify open issues/"holes"
– http://gaia.cs.umass.edu/rutgers_FIND_meeting
Synergies
• The main design drivers for the original Internet have changed
• Future Internet driven by
– Mobility
• Router, and network mobility
• Endpoint mobility (nodes and services)
– Disconnections
• Contemporaneous end-to-end path does not exist in many situations: special case
• Persistent storage in network nodes?
– Efficient Content Dissemination/Access
• Content-oriented networking
• Naming/Role-based networking/Late-binding of names
• Service-oriented networking
– Is this a special case of content-oriented networking?
• Are the above solved using a common overlay or in the core?
– Enhance core routing
– Redefine the functionality of the endpoint
OR
– Build a common overlay that takes advantage of the existing Internet
Mobility
• Some people think mobility is portability
– Disconnecting laptop from one Access Point and reconnecting at a
different Access Point
• What we mean by mobility is all of the below:
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–
–
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Endpoint moving continuously (laptop/cellphone in a car/bus)
Service moving in a seamless manner (VPN, Web, VoIP, Video)
Router carrying content as it moves
Network as a whole is moving
Disconnections/Opportunistic
• Some people think Disconnection is a long-term event
• What we mean by Disconnection/Opportunistic
Transport is all of the below:
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Disconnection resulting from “distance” (out of range transmissions)
Disconnection resulting from “shielding” (propagation)
Disconnection resulting from “low battery power”
Fluctuations resulting from time-varying nature of wireless links
(time-varying capacity as well as error rate)
• Transport opportunistically when link has higher capacity and lower
error rate
– Use a moving vehicle (entity) to cache, carry and opportunistically
transport content to another entity in the network
Content Dissemination/Access
• Some people think content dissemination is synonymous with
caching/mirroring infrastructure (e.g., Akamai)
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Deploy caching servers in select locations of the network
Replicate popular contents of a “customer” in the caching servers
Direct end-users to the “nearest” caching server
Centralized optimization and intelligence resides outside the network
• What we mean by content dissemination/access is all of the below:
– Content is “first class” element in the network; not a side-effect of clientserver conversation
– Content is explicitly requested by end-clients from the network
– Content “discovery” within the network
– Content “caching” within the network
– Content “routing” within the network
– Distributed optimization and intelligence resides inside the network
Common Architectural Framework
• Introduction of functionality in the “network” (ALL)
– Storage
– More hop-by-hop functionality
• A new kind of naming and addressing (TNA/DAN)
– Persistent identifiers for endpoints, roles, services
– Content addressability
• Leverage the existing DTNRG work and build on it
(BBN/Postcards)
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DTN Architecture
Bundle Protocol
Bundle Security Protocol
Metadata Extension Block
Implementations
Related algorithms
Open Problems
• Routing
– Scaleable integrated approaches that work in wired, wireless, mobile, and
DTN environments in an end-to-end manner
• Should we explore this as a theme in an upcoming FIND meeting?
– Interplay with name resolution and content (including queries)
• Discovery
– Content discovery
– Efficient peer/cache discovery and association
– Available service discovery
• Content
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Rights management
Privacy
Consistency and freshness management
Accounting (e.g., number of downloads of a movie/song)
• Designing the following into the system
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Network heterogeneity
Diagnostics and Manageability
Security
Context awareness
Participants
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Jim Kurose, UMass, Amherst (Postcards)
Sanjoy Paul, WINLAB, Rutgers U. (Postcards)
Roy Yates, WINLAB, Rutgers U. (Postcards)
Dipankar Raychaudhuri, WINLAB, Rutgers U. (Postcards)
Henry Jerez, CNRI/UNM (TNA)
Robin Kravets, UIUC (DAN)
Lars Lundgren, Ericsson (Ambient Networks)
Rajesh Krishnan, BBN (SPINDLE/DTN)
Thank you !
Questions ?
GENI Use Case
• Content (pictures, video clips, etc.) and Service (voice,
video, messaging, VPN) delivery where the senders
and/or receivers are mobile and may not be connected on
a continuous basis
– Mobile Host MH1 uploading a movie to Mobile Host MH2
– During the upload, MH2 gets disconnected due to mobility and
then reconnected at a different point in the network
– Fixed Host FH1 requests the same movie from the network
(content)
Mobile
Host (MH1)
Mobile
Host (MH1)
GENI Physical Network
Mobile
Host (MH2)
Mobile
Host (MH2)
PCN: Programmable
Core Node
PEN: Programmable
Edge Node
PWN2
PWN1
PWN7
PWN6
Wireless
subnet
PWN: Programmable
PWN5 Wireless Node
PWN4
Wireless
subnet
PEN1
PEN5
PWN3
PCN1
PEN4
PEN2
PCN5
PCN2
PCN3
PEN3
PWN6
Wireless
subnet
Fixed
Wireless
Host (FH1)
PCN4
-- Mobile Host
MH1 uploading a
movie to Mobile
Host MH2
-- During the
upload, MH2 gets
disconnected
due to mobility
and then
reconnected at a
different point in
the network
-- Fixed Host FH1
requests the
same movie from
the network
(content)
GENI Logical Network
Mobile
Host (MH2)
Mobile
Host (MH2)
PCN: Programmable
Core Node
PEN: Programmable
Edge Node
Wireless
subnet
Mobile
Host (MH1)
PWN7
PWN4Wireless
subnet
Wireless
subnet
PWN2
Wireless
subnet
PWN1
PWN6
PEN2
PWN3
PEN5
PEN1
PEN4
GENI
Backbone
PEN3
PWN6
Wireless
subnet
PWN: Programmable
Wireless Node
Wireless
subnet
Fixed
Wireless
Host (FH1)
PWN5
-- Mobile Host
MH1 uploading a
movie to Mobile
Host MH2
-- During the
upload, MH2 gets
disconnected
due to mobility
and then
reconnected at a
different point in
the network
-- Fixed Host FH1
requests the
same movie from
the network
(content)
1. MH1 deposits some chunks
of a file in PWN2 and later
some other chunks in PWN1
Mobile
Host (MH1)
PWN2
Mobile
Host (MH1)
Wireless
subnet
PWN1
Mobile
Host (MH2)
Mobile
Host (MH2)
3. As MH2’s point of
attachment changes,
chunks are forwarded
towards PWN7
4. Chunks not
delivered to MH2 are
redirected from
PWN4 to PWN7
PEN2
Wireless
subnet
Wireless
subnet
PWN7
PWN4Wireless
subnet
PWN5
Wireless
subnet
PWN6
PWN3
PEN5
PEN1
PEN4
GENI
Backbone
2. Chunks are forwarded
hop-by-hop towards MH2’s
point of attachment PWN4.
Chunks can be cached in
intermediate nodes
5. Request from FH1
for the same content
is served off PEN3
where it is cached
PEN3
PWN6
Wireless
subnet
Fixed
Wireless
Host (FH1)