Transcript Sensor Networks

Access Network for Future Internet
Deokjai Choi
2015. 3
Outline
 Changes of Networking
 Access Network Technologies
- Current
- Coming: Sensor Networks, WMNs, DTN
- Future ?
 Discussions
Changes of Networking
 Environment
- Trusted => Untrusted
 Users
- Researchers => Customers => Things
 Operators
- Nonprofits => Commercial
 Usages
- Host-oriented => Data-centric
 Connectivity
- E2E IP => Intermittent Connection
 Application Architecture
- Client-Server => P2P
New Networks and Services
 Home Networks
 PANs
 BANs
 CDN
 Sensor Networks, IoT
 Intelligent Things
 Context Aware Services
 Social Networks
 Smart Phone
Access networks
Q: How to connect end systems
to edge router?

residential access nets

institutional access
networks (school,
company)

mobile access networks
What is a Access Network?
 Existing World
- Customer Network, Access Network, Core Network (Hierarchical
structure)
- Accessed by residential user, customer organization, and mobile user
- Access to central server, core network for delivery packet
 Current and Coming World
- We do not know the structure since we are trying to design now.
- Even though there have been some researches for future internet
architecture in research societies, we still have not seen any concrete
one yet. It would not be soon to see the one.
- Even though strict hierarchical structure will be getting weak a little
because of P2P and CDN etc, but the principle of hierarchical structure
will remain as it is (eg. Roads)
New Project by NSF-CISE (Aug. 27, 2010 ~ )
7


Named Data Networking: Lixia Zhang(UCLA)
 Technical challenges: Routing scalability, fast forwarding,
trust model, network security, content protection and
privacy, and communication theory
Mobility First: Dipankar Raychaudhuri (Rutgers University)


NEBULA: Jonathan Smith (University of Pennsylvania)


Using GDTN, tradeoffs between mobility and scalability and on
opportunistic use of network resources to achieve effective
communications among mobile endpoints
The technical challenges in creating a cloud-computing-centric
architecture
eXpressive Internet Architecture: Peter Steenkiste (CMU)

Refine the interface between the network and users; analyzing the
relationship between technical design decisions and public policy
Networking Lab, Kyung Hee University
Access Networks
 Current Access Networks
- For home: ADSL,
- For Organization: T1, T3
- For mobile user: Wi-Fi, WiMAX, 3G, 4G,..
 Coming Access Networks for New Services
- No Change
- Static or mobile Human (Home, Office)
- wearable devices: through some kind of gateway
- New Service style
- Static or mobile Sensor Network (IoT)  New or Emerging Citizen
- Intermittent connection
Sensor Networks
 Sensor Networks
- Will be proliferated with wide usage such as environment monitoring,
surveillance monitoring, bridge and building safety monitoring etc.
- Most likely, they will have a sink node.
- A group of nodes is connected to the Internet through a sink node which
plays a role of gateway.
Why “Real” Information is so Important?
Save Resources
Improve Productivity
Enable New Knowledge
Increase
Comfort
Enhance Safety & Security
Preventing Failures
High-Confidence Transport
Improve Food
Protect Health
WSN Applications
 Monitoring Spaces
-
Env. Monitoring, Conservation biology, ...
Precision agriculture,
built environment comfort & efficiency ...
alarms, security, surveillance, …
 Monitoring Things
-
automated meter reading
condition-based maintenance
disaster management
Civil infrastructure
 Interactions of Space and Things
- manufacturing, asset tracking, fleet & franchise
- context aware computing, non-verbal communication
- Assistance - home/elder care
 Action and control
- Optimizing processes
- Automation
Canonical Sensor
Network Architecture
Patch
Network
Sensor Node
Sensor Node
Sensor Patch
Gateway
Gateway
Transit Network
(IP or not)
Access point
- Base station
- Proxy
Client Data Browsing
and Processing
Intranet/Internet (IP)
Other information
sources
Data Service
Ways of Connecting WSN to Internet
Proxy or Gateway
 Protocols for WSN are free choice.
 Two types: relay or front-end
 Relay
- Clients may register its interests to the proxy.
- Data are passed through
 Front-end
- The proxy proactively collects data from SN and stores them in its database,
and later responds to the query.
 Problems:
- single point of failure
- One proxy for one application; it may requires many proxy implementations.
examples of Gateway
Application gateway
- Works in application layer
- P2P USN Sharing (example)
DTN
- Works in network layer
- Bundle layer is to store and forward between networks
Overlay
TCP/IP overlay sensor network
- Each sensor node implements TCP/IP.
- Limited resource constraints problem.
- IP/USN, 6LowPAN
Sensor Network overlay TCP/IP
- Each TCP/IP node implements sensor node protocols.
- How many sensor node protocols should be implemented?
Could it be generalized?
Overlay - IP/USN
IP Lesson
 Separate the logical communication of information from the
physical links that carry the packets.
- Routing
- Security
Diverse Object and Data Models (HTML, XML, …)
Application (Telnet, FTP, SMTP, SNMP, HTTP)
Transport (UDP/IP, TCP/IP)
Internet Internet
ProtocolProtocol
(IP) Routing
(IP) Routing
Serial
802.3
802.5
GPRS X3T9.5
802.3a Token Ring
Modem
FDDI Ethernet
802.3i
Sonet
Ethernet
ISDN
802.3y
Ethernet
10b2
802.3ab
DSL
Ethernet
802.3an
10bT
Ethernet
100bT
Ethernet
1000bT
1G bT
802.11
802.15.4
802.11a
WiFi
LoWPAN
802.11b
WiFi
802.11g
WiFi
802.11n
WiFi
WiFi
But, …
 isn’t IP too heavyweight for low-power, wireless, microcontroller
based devices?

No!
 6lowpan compression with high quality multihop routing
- Reliability and lifetime of the best mesh
- Interoperability of IP
Gateway - P2P Approach to USN Integration
 Adopting P2P techniques, each USN with a gateway act as a peer
 The main goal of P2P overlay is to treat the underlying heterogeneou
s USNs as a single unified network, in which users can send queries
without considering the details of the network
 User peers communicate with gateway peers in a P2P approach
[Lei Shu, SAINT 2008]
P2P USN Approach
 General P2P overlay network for USN Service
- If a P2P peer software is installed in sink nodes, sensor nodes, and users,
all USNs can be shared by users and other USNs.
- USN application service is possible without knowing its target USNs
protocols.
 Service Scenarios
- A peer node (user) can find sensor networks which can provide sensor
information it wants.
- A USN can find other USN for collaboration
- A USN can find a peer node (user) which needs its sensory information
 Advantages
- Share already deployed sensor networks and need not deploy new sensor
networks for specific USN service.
- Exploit various information of USNs
- P2P USN becomes an infrastructure for general service providers
Sink Node Architecture
Application
1. Service description
ZigBee
Sink
module
2. request service
3. Sensing data
4. Clear to service
DB
P2P Overlay
module
TCP/IP
Sensor P2P Service for Sharing USNs
 P2P USN Service Scenario
- USN’s sink node or a sensor node can
be a P2P node and advertize own
services / information.
- a P2P node can also advertize
services / information it wants.
- a P2P node can find a service /
information it wants and ask it to
peer node.
- a sink node or sensor node can find a
peer node (user or other USN) which
wants its service / information and
provide that.
(Sensor P2P Layer)
Overlay Network Layer
(Forwarding)
KOREN
Sink
Sensor
Sensor Network
Peer
Node
Overlay
Node
P2P USN Service Scenarios
 An Application server finds and gathers information.
Sensor P2P
Overlay Network
Server
Internet
User
Peer
Node
Sensor
Network
 Sensor network looks for users, if special events happen
User
Event
Sensor
Network
Sensor P2P
Overlay Network
User
User
Unstable Connection
ex: SpoVNet
 Spontaneous Virtual Networks
- Connecting Sensor Network Islands to the Future Internet using the
SpoVNet Architecture
Motivation/Objectives
 Heterogeneity of network technologies makes the controllability
of complex, global communication systems difficult.
 SpoVNet follows the approach of providing spontaneous
communication by composing algorithms and protocols that
allow self-organization in distributed systems.
 Self-organizing systems are able to adapt to the given
requirements and network loads flexibly, without further
involvement of administrative expenditure.
 The main objective of spovnets is to provide the actual arising
service needs spontaneously, autonomously and adaptively
Cargo Tracking System
 Today’s Cargo tracking system
- Consist of GPS receiver and a mobile phone unit
- Attached to the actual cargo container
- allows tracking of container locations
 Online monitoring tracking system
- The GSM unit in current location tracking systems is not limited to the
transfer of GPS coordinates, but also of other sensor information too.
- To reduce costly GSM communication, Several containers can use a
single GSM unit that is attached to a dedicated container.
- Cost and availability of GSM communication is still problematic and
only allows transmission of data at large intervals
Cargo Tracking System
 However, It is not satisfying
- No continuous connectivity is available, therefore disallowing
online monitoring
- Communication is costly, making monitoring expensive
 So, they employed a new Container Monitoring Application
(CMA) on top of SpoVNet that uses SNS to access sensor
network islands and performed the actual communication for
monitoring application.
SpoVNet
Sensor Network Service and Container Monitoring
Application in the SpoVNet Architecture
Future Internet Access Network Technologies:
Delay Tolerant Network (for another unstable
connection)
Motivation
 Evolve wireless networks outside the Internet
- Problems with inter-networks having operational and performance
characteristics that make conventional networking approaches either
unworkable or impractical.
- Accommodate the mobility and limited power of future wireless
devices
 Examples of wireless networks outside the Internet:
- Terrestrial civilian networks connecting mobile wireless devices
including personal communicators, intelligent highway and remote
Earth outposts.
- Wireless military battlefield networks connecting troops, aircraft,
satellites and sensors (on land or water)
- Outer-space networks, such as the “Interplanetary
communications”.
Internet Evolving Concept
Why DTNs?
 Current Internet was designed for
- Continuous, bidirectional end-to-end path
- Short round-trips
- Symmetric data rates
- Low error rates
 Many evolving and challenged networks do not confirm to the
current Internet’s philosophy
- Intermittent connectivity
- Long or variable Delay
- Asymmetric data rates
- High error rates
DTN Concept
 Build upon the extended “bundling”
architecture (an end-to-end messageoriented overlay)
- Proposes and alternative to the Internet
TCP/IP end-to-end model.
- Employs hop-by-hop storage and
retransmission as a transport-layer overlay.
- Provides messaging service interface (similar
to electronic mail)
 The wireless DTN technologies may be
diverse
- E.g.: RF, UWB, free-space optical, acoustic
(solar or ultrasonic) technologies …
Current Internet vs. DTN Routing
Types of DTN contacts
 Persistent contacts
Types of DTN contacts
 Persistent contacts
 On-demand contacts
Types of DTN contacts
 Persistent contacts
 On-demand contacts
 Intermittent –
scheduled contacts
(predicted contact)
Types of DTN contacts
 Persistent contacts
 On-demand contacts
 Intermittent –
scheduled contacts
(predicted contact)
 Intermittent – opportunistic
contacts
DTN Routing Approach
 Probabilistic Routing
- Probabilistic routing methods use nodes' past encounter records to predict their future
encounter probabilities
 Social-Network Based Routing
- Groups frequently encountered nodes into a cluster for efficient intracommunity
communication and selects nodes having frequent contacts with foreign communities
for intercommunity communication.
 Location-Based Routing
- Location-based routing methods use previous geographical location to assist packet
routing in DTNs
 Inter-Landmark Routing
- Selects popular places that nodes visit frequently as landmarks and divides the entire D
TN area into subareas represented by landmarks
DTN Probabilistic Routing
 Based on assumption that real users are
not likely to move around randomly
 Real users have tendency to move in a
predictable fashion based on repeating
behavioral patterns
 Example : if a node has visited a location
several times before, it is likely to visit
that location again.
 Example : if a pair of nodes has made
contact several times, it is likely to made
contact again.
DTN Probabilistic Routing
 When two nodes meet, they exchange
summary data which also contain the
delivery predictability information
 The data will be transferred to the other
node if the delivery predictability is
higher than current nodes
 Reference Project : PROPHET
(Probabilistic Routing Protocol using His
tory of Encounters and Transitivity)
 Reference : A. Lindgren, A. Doria, and O. Schelén, “Proba
bilistic routing in intermittently connected networks,” Mobile
Comput. Commun. Rev., vol. 7, no. 3, pp. 19–20, 2003.
DTN Social-Network Based Routing
 Based on social networks attribute
 Social networks exhibit the small world
phenomenon which comes from the
observation that individuals are often
linked by a short chain of acquaintances
 Node encounters are sufficient to build a
connected relationship graph, which is a
small world graph
 Node encounters classified into 2 types :
- Intracommunity encounters
- Intercommunity encounters
DTN Social-Network Based Routing
 In the example : Source S want to send
message to destination D
 Need to find the “bridge” which is the
path connecting three clusters
 In the figure, i1 have weak acquaintance
ties with i2, and i3 also have weak
acquaintance ties with i4
 These “ties” can make a path/bridge to
forward data, the connection between
the clusters would not exist if there is no
ties
 Reference Project : SimBet Routing
 Reference : E. M. Daly and M. Haahr, “Social network anal
ysis for routing in disconnected delay-tolerant MANETs,” in
Proc. ACM MobiHoc, 2007,pp. 32–40.
DTN Location-Based Routing
 Based on notion of location distribution, which calculated using location information
and frequency from node history
 Upon the meeting of two nodes, our approach compares their distributions and
chooses the subsequent carrier for a message bundle accordingly
DTN Location-Based Routing
 Routing decision based on previous node movements with a probabilistic node
meeting heuristic
 The nodes’ movement patterns are reactively compared to the destination’s pattern
 The probabilistic meeting score denoting of how probable it is that node and the
destination node have a common movement domain
 Reference Project : GeoDTN (Geographic Routing in Disruption Tolerant Networks)
 Reference : J. Link, D. Schmitz, and K. Wehrle, “GeoDTN: Geographic routing in disruption tolerant networks,” in Proc. IEE
E GLOBECOM, 2011, pp. 1–5.
DTN Inter-Landmark Routing
 Based on combination from probabilistic
routing and location-based routing
 From the information of how frequent a
node visit an area, landmark is selected
 Each landmark, configured with a central
station, will determine the route to the
destination area
 Each node transit on landmark will relay
packet to the next landmark
 This routing does not only rely on nodes
that frequently visit packet's destination
to forward the packet, but utilize all
nodes mobility
 Reference Project : DTN-FLOW
 Reference : K. Chen and H. Shen, "DTN-FLOW: Inter-Land
mark Data Flow for High-Throughput Routing in DTNs," IE
EE/ACM TRANSACTIONS ON NETWORKING, vol. 23, no
. 1, pp. 212-225, 2015.
Discussions
 Future Internet ?
- We do not know the picture at this moment.
 Access Network?
- We can think still there will be need to connect small things
(sensors, gadget, or mobile devices) to the NETWORKs.
 Major Candidates
- Sensor Networks
- SpoVNET style
- DTN