a constructive review of in network caching a core functionality of icn slides
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A Constructive Review of In-Network Caching: A Core Functionality of ICN*
Anshuman Kalla
1Anshuman Kalla
* A. Kalla and S. K. Sharma, "A constructive review of in-network caching: A core functionality of ICN," 2016 International Conference on Computing, Communication and Automation (ICCCA), Noida, 2016, pp. 567-574. DOI: 10.1109/CCAA.2016.7813785
Square brackets ‘[ ]’ denotes the reference number as per the reference list in the paper
Introduction
• ICN conceives caching at network layer as one of the indispensable core functionalities of ICN
– beyond the premise of end-to-end principle
2Anshuman Kalla
Introduction
• ICN conceives caching at network layer as one of the indispensable core functionalities of ICN
– beyond the premise of end-to-end principle
• Moreover, ICN advocates named-contents instead of named-hosts
3Anshuman Kalla
Introduction
• ICN conceives caching at network layer as one of the indispensable core functionalities of ICN
– beyond the premise of end-to-end principle
• Moreover, ICN advocates named-contents instead of named-hosts
• Together the two functionalities result in content-aware in-network caching is configured
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Introduction
• The idea is to allow caching at network layer
– That is routers are configured with Content Stores (cache facility) that enable them to cache the contents traversing them
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Introduction
• The idea is to allow caching at network layer
– That is routers are configured with Content Stores (cache facility) that enable them to cache the contents traversing them
• Thus every node, in addition to routing, buffering and forwarding operations
– should perform caching of (traversing) contents
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Review of Literature
March 7, 2017 7Anshuman Kalla
Factors Affecting In-Network Caching
Aim of review ofIn-Network Caching
Relevant Performance Metrics
Network Topologies Exploited
Traffic Patterns Fed
Simulators Available for Evaluation
Issues Related to In-Network Caching
Advantages of In-Network Caching
Issues Related to TCP/IP Networking [1],[2]
1. Data Dissemination & Service Access (prominent usage today)
– Current networking was tailored to share networking resources
Anshuman Kalla 8* See paper for all the references
Issues Related to TCP/IP Networking [1],[2]
1. Data Dissemination & Service Access (prominent usage today)
– Current networking was tailored to share networking resources
2. Named Hosts (i.e. IP address do actually exist in current network)
– Content name (identifier) IP address (locator) i.e. DNS lookup
Anshuman Kalla 9* See paper for all the references
Issues Related to TCP/IP Networking [1],[2]
1. Data Dissemination & Service Access (prominent usage today)
– Current networking was tailored to share networking resources
2. Named Hosts (i.e. IP address do actually exist in current network)
– Content name (identifier) IP address (locator) i.e. DNS lookup
3. Mobility (was least imagined when TCP/IP was designed)
– Leads to intermittent connectivity results in change in IP
Anshuman Kalla 10* See paper for all the references
Issues Related to TCP/IP Networking [1],[2]
1. Data Dissemination & Service Access (prominent usage today)
– Current networking was tailored to share networking resources
2. Named Hosts (i.e. IP address do actually exist in current network)
– Content name (identifier) IP address (locator) i.e. DNS lookup
3. Mobility (was least imagined when TCP/IP was designed)
– Leads to intermittent connectivity results in change in IP
4. Availability (of content and/or service with min. possible latency)
– Dependent on node/link/server state
Anshuman Kalla 11* See paper for all the references
Issues Related to TCP/IP Networking [1],[2]
1. Data Dissemination & Service Access (prominent usage today)
– Current networking was tailored to share networking resources
2. Named Hosts (i.e. IP address do actually exist in current network)
– Content name (identifier) IP address (locator) i.e. DNS lookup
3. Mobility (was least imagined when TCP/IP was designed)
– Leads to intermittent connectivity results in change in IP
4. Availability (of content and/or service with min. possible latency)
– Dependent on node/link/server state
5. Security (implies comm. over secured channel & trusted server)
– So far implemented at network-level but missing at content-level
Anshuman Kalla 12* See paper for all the references
Issues Related to TCP/IP Networking [1],[2]
1. Data Dissemination & Service Access (prominent usage today)
– Current networking was tailored to share networking resources
2. Named Hosts (i.e. IP address do actually exist in current network)
– Content name (identifier) IP address (locator) i.e. DNS lookup
3. Mobility (was least imagined when TCP/IP was designed)
– Leads to intermittent connectivity results in change in IP
4. Availability (of content and/or service with min. possible latency)
– Dependent on node/link/server state
5. Security (implies comm. over secured channel & trusted server)
– So far implemented at network-level but missing at content-level
6. Flash Crowd leads to congestion, DoS, poor QoS etc.Anshuman Kalla 13* See paper for all the references
The Trend For Problem Solving
• Dedicated patch(es) for each problem encountered (for ex.)– CDN and P2P for data dissemination
– DNS for Named Host (i.e. to resolve any name to IP address)
– MobileIP for mobility
– DNSSec and IPSec for security
– Web caching or CDN for availability
Anshuman Kalla 14
The Trend For Problem Solving
• Dedicated patch(es) for each problem encountered (for ex.)– CDN and P2P for data dissemination
– DNS for Named Host (i.e. to resolve any name to IP address)
– MobileIP for mobility
– DNSSec and IPSec for security
– Web caching or CDN for availability
• These patches/fixes are add-on (not integral) – Thus transforming TCPIP networking into complex & delicate architecture
Anshuman Kalla 15
The Trend For Problem Solving
• Dedicated patch(es) for each problem encountered (for ex.)– CDN and P2P for data dissemination
– DNS for Named Host (i.e. to resolve any name to IP address)
– MobileIP for mobility
– DNSSec and IPSec for security
– Web caching or CDN for availability
• These patches/fixes are add-on (not integral) – Thus transforming TCPIP networking into complex & delicate architecture
• Shift in primary usage of networking facility– Instead sharing of network resources prime usage is content centric
Anshuman Kalla 16
The Trend For Problem Solving
• Dedicated patch(es) for each problem encountered (for ex.)– CDN and P2P for data dissemination
– DNS for Named Host (i.e. to resolve any name to IP address)
– MobileIP for mobility
– DNSSec and IPSec for security
– Web caching or CDN for availability
• These patches/fixes are add-on (not integral) – Thus transforming TCPIP networking into complex & delicate architecture
• Shift in primary usage of networking facility– Instead of sharing network resources prime usage is content centric
• Lately researchers realized need for clean-slate approach – To reconcile all the issues (and shift in usage) in a unified manner
Anshuman Kalla 17
Core Functionalities of ICN
• Named content
• In-network caching
• Named based routing
• Data-level security
• Multi-path routing
• Hop-by-hop flow control
• Pull-based communication
• Adaptability to Multiple simultaneous connectivities
Anshuman Kalla 18
Core Functionalities of ICN
• Named content
• In-network caching
• Named based routing
• Data-level security
• Multi-path routing
• Hop-by-hop flow control
• Pull-based communication
• Adaptability to Multiple simultaneous connectivities
Anshuman Kalla 19
Types of In-Network Caching in ICN
March 7, 2017 20Anshuman Kalla
In-Network Caching
Off-Path Caching Edge CachingOn-Path Caching
Hybrid Caching
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• On-Path Caching
– Caches the retrieved contents at the intermediate nodes that fall on the (symmetrical) way back from server to the requester
– Thus interest taps nodes falling on-the-path from requester to server
Types of In-Network Caching in ICN
March 7, 2017 22Anshuman Kalla
• On-Path Caching
– Caches the retrieved contents at the intermediate nodes that fall on the (symmetrical) way back from server to the requester
– Thus interest taps nodes falling on-the-path from requester to server
• Off-Path Caching– Appoints node(s) as a dedicated cache(s) for a retrieved content
– Selected caches have no contrived correlation with the nodes that fall on the path being followed by interest to reach the server
Types of In-Network Caching in ICN
March 7, 2017 23Anshuman Kalla
• On-Path Caching
– Caches the retrieved contents at the intermediate nodes that fall on the (symmetrical) way back from server to the requester
– Thus interest taps nodes falling on-the-path from requester to server
• Off-Path Caching– Appoints node(s) as a dedicated cache(s) for a retrieved content
– Selected caches have no contrived correlation with the nodes that fall on the path being followed by interest to reach the server
• Edge Caching
– Opposes pervasive in-network caching
– Only the nodes at the boundary of a network are enabled with caching capability
Types of In-Network Caching in ICN
Types of In-Network Caching in ICN
Interest Packet
Data Packet
R8 R7 R6
R1
R2
R3R4
R5
R1
R2
R3R4
R5R8 R7 R6
R1
R2
R3R4
R5R8 R7 R6
Nodes that could cache data
On-Path Caching(R1, R2, R3, R6 – On-Path Caches)
Off-Path Caching(R4 – Designated Off-Path Cache)
Edge Caching(R6 – Edge Cache)
Advantages of In-Network Caching in ICN
1. Cost Effective Data Retrieval– Minimizes delegation of traffic for cached contents over egress links
– Thereby minimizes traffic over expensive external links and server load
Anshuman Kalla 25* See paper for all the references
Advantages of In-Network Caching in ICN
1. Cost Effective Data Retrieval– Minimizes delegation of traffic for cached contents over egress links
– Thereby minimizes traffic over expensive external links and server load
2. Reduction in Latency– Since contents are cached at comparatively closer intermediate nodes
– Thereby improves Quality-of-Service (QoS) perceived by users
Anshuman Kalla 26* See paper for all the references
Advantages of In-Network Caching in ICN
1. Cost Effective Data Retrieval– Minimizes delegation of traffic for cached contents over egress links
– Thereby minimizes traffic over expensive external links and server load
2. Reduction in Latency– Since contents are cached at comparatively closer intermediate nodes
– Thereby improves Quality-of-Service (QoS) perceived by users
3. Heavy Load Handling– Caching transforms nodes into legitimate proxies of origin server
– Thereby inherently tackles heavy load situations like flash crowd
Anshuman Kalla 27* See paper for all the references
Advantages of In-Network Caching in ICN
1. Cost Effective Data Retrieval– Minimizes delegation of traffic for cached contents over egress links
– Thereby minimizes traffic over expensive external links and server load
2. Reduction in Latency– Since contents are cached at comparatively closer intermediate nodes
– Thereby improves Quality-of-Service (QoS) perceived by users
3. Heavy Load Handling– Caching transforms nodes into legitimate proxies of origin server
– Thereby inherently tackles heavy load situations like flash crowd
4. Efficient Retransmissions– Caching allows retransmission of content’s cached copy from closest node
– Thereby ensures better resiliency to packet losses
Anshuman Kalla 28* See paper for all the references
Advantages of In-Network Caching in ICN
5. Higher Availability – More legitimate proxies of server i.e. caches improves content availability
– Thereby reduces the probability of Denial of Service (DoS) attack
Anshuman Kalla 29* See paper for all the references
Advantages of In-Network Caching in ICN
5. Higher Availability – More legitimate proxies of server i.e. caches improves content availability
– Thereby reduces the probability of Denial of Service (DoS) attack
6. Buoyancy to Intermittent Connectivity– Caching inherently allows to sustain intermittent connectivity
– Also allows mobile nodes to act as a network medium for areas uncovered by network
Anshuman Kalla 30* See paper for all the references
Issues Related to In-Network Caching in ICN
1. Cache Placement or Allocation– Where to place the caches (i.e. content stores)?
– That is caching facility at all or selected nodes in a network
– Edge nodes / core nodes / central nodes / strategically selected nodes
Anshuman Kalla 31* See paper for all the references
Issues Related to In-Network Caching in ICN
1. Cache Placement or Allocation– Where to place the caches (i.e. content stores)?
– That is caching facility at all or selected nodes in a network
– Edge nodes / core nodes / central nodes / strategically selected nodes
2. Cache Size Dimensioning– What should be the size of caches?
– That is allowing homogeneous or heterogeneous caches
– In case of heterogeneous where to boost cache size comparatively
Anshuman Kalla 32* See paper for all the references
Issues Related to In-Network Caching in ICN
1. Cache Placement or Allocation– Where to place the caches (i.e. content stores)?
– That is caching facility at all or selected nodes in a network
– Edge nodes / core nodes / central nodes / strategically selected nodes
2. Cache Size Dimensioning– What should be the size of caches?
– That is allowing homogeneous or heterogeneous caches
– In case of heterogeneous where to boost cache size comparatively
3. Content Placement– Where to cache a retrieved content within a network?
– That is where to cache the retrieved content to improve performance
– Centralized or decentralized manner (explicit or implicit coordination)
Anshuman Kalla 33* See paper for all the references
Issues Related to In-Network Caching in ICN
4. Content Selection– What to cache out of huge flow of contents?
– That is to identify profitable contents from content catalog for caching
– Could be performed event after content placement if the placement mechanism is oblivious of content’s utility characteristics
Anshuman Kalla 34* See paper for all the references
Issues Related to In-Network Caching in ICN
4. Content Selection– What to cache out of huge flow of contents?
– That is to identify profitable contents from content catalog for caching
– Could be performed event after content placement if the placement mechanism is oblivious of content’s utility characteristics
5. Replacement policy– Which cached-content should be evicted to accommodate an incoming
content?
– That is when cache is full then which residing content to be evicted to cache the retrieved content
Anshuman Kalla 35* See paper for all the references
Factors Affecting In-Network Caching in ICN
1. Network topology – Its cognizance might be crucial for performing caching
Anshuman Kalla 36* See paper for all the references
Factors Affecting In-Network Caching in ICN
1. Network topology – Its cognizance might be crucial for performing caching
2. Size of Content Population (Content Catalog)– Total number of distinct contents for which request could be received
Anshuman Kalla 37* See paper for all the references
Factors Affecting In-Network Caching in ICN
1. Network topology – Its cognizance might be crucial for performing caching
2. Size of Content Population (Content Catalog)– Total number of distinct contents for which request could be received
3. Popularity Distribution – Plays vital role but popularity estimation is itself a challenging task
Anshuman Kalla 38* See paper for all the references
Factors Affecting In-Network Caching in ICN
1. Network topology – Its cognizance might be crucial for performing caching
2. Size of Content Population (Content Catalog)– Total number of distinct contents for which request could be received
3. Popularity Distribution – Plays vital role but popularity estimation is itself a challenging task
4. Popularity Dynamics– Percentage and/or frequency of change in popularity of contents
Anshuman Kalla 39* See paper for all the references
Factors Affecting In-Network Caching in ICN
1. Network topology– Its cognizance might be crucial for performing caching
2. Size of Content Population (Content Catalog)– Total number of distinct contents for which request could be received
3. Popularity Distribution – Plays vital role but popularity estimation is itself a challenging task
4. Popularity Dynamics – Percentage and/or frequency of change in popularity of contents
5. Latency – In terms of hop-count or distance, used to trigger caching decision
Anshuman Kalla 40* See paper for all the references
Factors Affecting In-Network Caching in ICN
6. Bandwidth– Available over retrieval path is another factor used for caching decision
Anshuman Kalla 41* See paper for all the references
Factors Affecting In-Network Caching in ICN
6. Bandwidth– Available over retrieval path is another factor used for caching decision
7. Cache size per node – Homo or heterogeneous sized caches to analyze caching performance
Anshuman Kalla 42* See paper for all the references
Factors Affecting In-Network Caching in ICN
6. Bandwidth– Available over retrieval path is another factor used for caching decision
7. Cache size per node – Homo or heterogeneous sized caches to analyze caching performance
8. Granularity of content – Entire object or packet or chunk – granularity may affect performance
Anshuman Kalla 43* See paper for all the references
Factors Affecting In-Network Caching in ICN
6. Bandwidth– Available over retrieval path is another factor used for caching decision
7. Cache size per node – Homo or heterogeneous sized caches to analyze caching performance
8. Granularity of content – Entire object or packet or chunk – granularity may affect performance
9. Size of Content– Homogeneous (small or large sized) or heterogeneous sized contents
Anshuman Kalla 44* See paper for all the references
Factors Affecting In-Network Caching in ICN
6. Bandwidth – Available over retrieval path is another factor used for caching decision
7. Cache size per node – Homo or heterogeneous sized caches to analyze caching performance
8. Granularity of content – Entire object or packet or chunk – granularity may affect performance
9. Size of Content– Homogeneous (small or large sized) or heterogeneous sized contents
10.Pricing (Cost involved in fetching contents)
– In order to prioritize caching of costlier contents
Anshuman Kalla 45* See paper for all the references
Factors Affecting In-Network Caching in ICN
11. Mobility– Movement tendency of users for pre-fetching based caching
Anshuman Kalla 46* See paper for all the references
Factors Affecting In-Network Caching in ICN
11. Mobility – Movement tendency of users for pre-fetching based caching
12. Routing– Multipath routing affects the caching performance differently
Anshuman Kalla 47* See paper for all the references
Factors Affecting In-Network Caching in ICN
11. Mobility – Movement tendency of users for pre-fetching based caching
12. Routing– Multipath routing affects the caching performance differently
13. Spatial Locality– Accessing tendency of user in a geographical area for caching decisions
Anshuman Kalla 48* See paper for all the references
Factors Affecting In-Network Caching in ICN
11. Mobility – Movement tendency of users for pre-fetching based caching
12. Routing– Multipath routing affects the caching performance differently
13. Spatial Locality– Accessing tendency of user in a geographical area for caching decisions
14. Social Networking– Caching of contents accessed or produced by socially active & influential
users
Anshuman Kalla 49* See paper for all the references
Performance Metrics For In-Network Caching
1. Hit Ratio– Number of satisfied requests by caching to total number of requests
– Higher is hit ratio better is the caching performance
Anshuman Kalla 50* See paper for all the references
Performance Metrics For In-Network Caching
1. Hit Ratio– Number of satisfied requests by caching to total number of requests
– Higher is hit ratio better is the caching performance
2. Bandwidth Usage– Implies usage of expensive external links as well as internal links
– Lower bandwidth usage implies better caching performance
Anshuman Kalla 51* See paper for all the references
Performance Metrics For In-Network Caching
1. Hit Ratio– Number of satisfied requests by caching to total number of requests
– Higher is hit ratio better is the caching performance
2. Bandwidth Usage– Implies usage of expensive external links as well as internal links
– Lower bandwidth usage implies better caching performance
3. Cache Load– Number of contents to be cached by a content store
– Homo or heterogeneously loaded cached
– Later leads to unbalanced caches & creation of hot spots
Anshuman Kalla 52* See paper for all the references
Performance Metrics For In-Network Caching
1. Hit Ratio– Number of satisfied requests by caching to total number of requests
– Higher is hit ratio better is the caching performance
2. Bandwidth Usage– Implies usage of expensive external links as well as internal links
– Lower bandwidth usage implies better caching performance
3. Cache Load– Number of contents to be cached by a content store
– Homo or heterogeneously loaded cached
– Later leads to unbalanced caches & creation of hot spots
4. Server Load– Number of content-requests arriving at original server
– Lower the server load better will be service provided Anshuman Kalla 53
Performance Metrics For In-Network Caching
5. Latency – Implies delay encountered in retrieving a requested content
– Lower latency boosts Quality-of-Experience (QoE) perceived by users
– Thus reduction in latency achieved is used to gauge caching performance
Anshuman Kalla 54* See paper for all the references
Performance Metrics For In-Network Caching
5. Latency – Implies delay encountered in retrieving a requested content
– Lower latency boosts Quality-of-Experience (QoE) perceived by users
– Thus reduction in latency achieved is used to gauge caching performance
6. Cache Diversity– Implies number of unique contents residing in network caches
– Higher cache diversity improves overall performance
Anshuman Kalla 55* See paper for all the references
Performance Metrics For In-Network Caching
5. Latency – Implies delay encountered in retrieving a requested content
– Lower latency boosts Quality-of-Experience (QoE) perceived by users
– Thus reduction in latency achieved is used to gauge caching performance
6. Cache Diversity– Implies number of unique contents residing in network caches
– Higher cache diversity improves overall performance
7. Complexity & Overheads– Caching needs to be simple, light-weight and practically deployable
Anshuman Kalla 56* See paper for all the references
Performance Metrics For In-Network Caching
5. Latency – Implies delay encountered in retrieving a requested content
– Lower latency boosts Quality-of-Experience (QoE) perceived by users
– Thus reduction in latency achieved is used to gauge caching performance
6. Cache Diversity– Implies number of unique contents residing in network caches
– Higher cache diversity improves overall performance
7. Complexity & Overheads– Caching needs to be simple, light-weight and practically deployable
8. Fairness– In terms of content selection fairness, link load fairness, popularity
estimation fairness etc.
Anshuman Kalla 57* See paper for all the references
Performance Metrics For In-Network Caching
9. Resiliency to DoS Attack – Network caching transforms caches into legitimate proxies of origin server
– Thus caches collectively handles DoS attack by divide-and-conquer rule
Anshuman Kalla 58* See paper for all the references
Real Network Topologies
• Abilene [14]
• Rocketfuel [12]
• CERNET2 [9]
• CAIDA [10]
• CRAWDAD [15]
• CERNET [16]
Anshuman Kalla 59
• GEANT [17]
• Tiger [18]
• GARR [19]
• WIDE [20]
• PlanetLab [21]
* See paper for all the references
Fabricated Network Topologies
• Barabasi-Albert (BA) Power Law Model [11]
• Watts-Strogatz (WS) Model [13]
• Boston university Representative Internet Topology gEnerator (BRITE) Tool [22]
• Gorgia Tech -Internetwork Topology Models (GT-ITM)Tool [23]
• Internet Topology Generator (INET) Tool [24]
Anshuman Kalla 60* See paper for all the references
Traffic Patterns
• Synthetic traffic workload have been generated using
– Zipf distribution (α ranging between 0.6 to 1.8) and
– Zipf-Mandelbrot distribution (with different value of α and q)
• Real traffic traces that have been used are
– P2P Workload [36]
– LastFM [32]
– Facebook data [33]
Anshuman Kalla 61* See paper for all the references
Network Simulators For ICN
• ccnSim simulator [25]
• CCNx simulator [26]
• OPNET simulator [27]
• CCNPL simulator [28]
• OMNET++ simulator [29]
• ICARUS simulator [30]
• NEPI simulator [31]
Anshuman Kalla 62* See paper for all the references
References
The reference list remains the same that is used in the original paper
Anshuman Kalla 63* See paper for all the references