Routing papers in ccn

INFORM: a dynamic Interest FORwarding for Information Centric Networking

By R. Chiocchetti et al.Presented by: Haroon Rashid

2

INFORM design goals

i. To discover paths to temporary copies of a content item

ii. To forward requests for such content items towards the « best » interface

iii. To guarantee data delivery

iv. To limit the network overhead

3

INFORM Working

A B

C

Interfaces

D

Producer

Consumer

4

Evaluation – Average packet download time

• The download time decreases as the connectivity increases

5

Evaluation – Average packet download time (cont'd)

• Delivery time sharply decreases as the cache size until additional storage capacity does not provide any benefits

6

Take aways

Efficiency of algorithm depends upon the frequency (Popularity) of requested file. E.g., works well in YouTube, Google News etc.

Accuracy of best interface estimation depends upon Nr.

7

NLSR: Named-data Link State Routing ProtocolBY: A K M Hoque et al.

8

NLSR

Intra Domain routing protocol Link state Use device names for identification instead of IP

addresses Produces multiple paths to same destination with

relative associated cost(hop count)

9

Approach

Each router advertizes LSA. Adjacency LSA -- set of active links at router. Prefix LSA -- name prefix registered with a router.

Each router stores LSA into LSDB.

Different LSA Types

10

Route Calculation

At each router (i) through each neighbor (v) for a particular destination (d) Dijkstra’s algorithm is run. This gives a list of next hop ranked neighbors for a particular destination (d).

This fine grained information is inserted into FIB.

i

v

v

V1

V2

V3

d

v

v

11

LSDB Synchronization

Router A Router B

12

Eval: Convergence with & without Multipath support

13

A Two-layer Intra-domain Routing Scheme for Named Data NetworkingBy: H. Dai et al.

14

Deals with:

Intra-domain routing. Two layer routing protocol:

Lower layer: Topology Maintaining (TM) Layer Upper layer: Prefix Announcing (PA) Layer

Active Publishing/Passive Serving Trade-offs between active publishing and passive

serving

15

TM Layer: Maintains full topology of the entire network i.e.,

connectivity and bandwidth. Provides shortest paths information as a service to

upper layer (PA). PA Layer:

Publishes content (prefix) that a router wants to serve Routers build their FIB on receiving prefixes.

16

PA Layer

Com/google/maps/USA/CA/Anaheim

17

Scalability

Large Network -> More routers ->More Publishing -> FIB explosion

Active publishing vs. Passive Serving Active publishing -> FIB explosion Passive Serving -> Traffic explosion

Solution lies in content popularity More Popular - Publish otherwise serve passively

18

Data popularity based approach

Publish the popular content and serve passively unpopular content.

Popularity property – access frequency Access frequency should be greater than particular

threshold. Large threshold -> massive interest flooding Small threshold -> large sized FIB

FIB suppression: Each announcement have threshold value (a) Each router have its own threshold value (p)

Depends upon memory size and other factors. If a>p, insert into FIB and relay otherwise relay only.

19

Cost Ratio Cost Ratio=Ppassive/Cactive

Evaluation: Cost Ratio

Where, In Ppassive: N – is consumer Node1 is producer dN – degree of node In Cactive : E,L - # of edges

20

Eval: Active vs. Passive mode comp.

• It is non-trivial to calculate the threshold value• As P increase less content is published and FIB size decreases.

Whereas more traffic gets generated for the content as served passively

21

Adaptive Forwarding In Named Data Networking By: C Yi et al.

22

Goal: Retrieve data through best performing path Detect packet delivery problems and their recovery.

Problem Identified in current architecture Interest not satisfied by a node -> No feedback to the

requesting node -> only timer helps. Within duration of timer lots of interests get piled up.

AB

E

CD

SInterest Interest

Inte

rest

Interest

Solution:Interest NACK packet

23

Interest NACK: Carries same name as Interest packet. Carries an error code explaining NACK generation

Congestion , No path etc.

Interface Ranking Based on Routing preference (neighbor biased) Observed forwarding performance (past history) Forwarding policy set by operators