How To Write A Multi-Core, Non-Relational, Non Relational, Non Synchronous, Non Unreliable, Non Reliable, Non Transactional, Nonrelational Database On A Microsoft Server
|
|
- Sharon Shaw
- 3 years ago
- Views:
Transcription
1 Online Reliable State Persistence Andrei Agapi Rick Payne Robert Broberg Thilo Kielmann FRIAR 2011
2 Outline FTSS. The KVL data model Communication (& other optimizations) BGP. BGP/KVL Distributed inodes Snaphots & complex queries Evaluation
3 FTSS overview Fast, malleable, non-relational DB, can be used as FT shared storage substrate for dynamic app state In-memory, 1-hop, perf-optimized DHT Independently failing components participate, all state replicated on several such & accessible from all Components self-monitor, membership maintained dynamically as they fail/(re)join malleable shmem Support for arbitrary structured data ~ navigational DB
4 FTSS overview [2] Perf. optimized, e.g. data bulking, optimized link/unlink ops, write-intensive API: Overwrite Append Delete Fetch Link Unlink Read links > Complex queries Each with bulk versions
5 Consistent Hashing-Based As SEs join/fail, tuples are remapped: A <- 6,4 C <- 3 B <- 2 D <- 5,1
6 Consistent Hashing-Based
7 Types of nodes Storage server Client (e.g. app persisting its state) Monitor app (global statistics, snapshoting etc)
8 The KVL model K Key, unique, used for distribution/replication over servers; V Value associated with key Tuples randomly spread based on hashed keys Can be updated: Overwritable, appendable All are symetrically replicated Linked list at server L Links / unique set Building block for handling structured data, arbitrary pointers, recovery indices, sets etc b-tree at server, serialized at read/replication time
9 Relevance for Next-Gen Routing: FT BGP. And impl. status Used actively in FT BGP: BGP daemon persists essential state as structured FTSS data: raw updates before ACK, processed state etc FTSS -> fail-stop failures, Byzantine can be orthogonally handled on top via other techniques (e.g. equivalent state machines) 1 BGP update=several FTSS writes, links, possibly deletes
10 Performance optimizations Copy reductions, malloc reductions along stack, in-memory locking etc Microbenchmarking + rewriting for performance Delaying block serialization for read / re-replication time as opposed to write time Tuning of chunk sizes, cache sizes, direct IO, etc Bulk ops & chunking
11 Communication Unicast (single key) updates Multicast updates Multi-key (bulk) updates
12 Communication: Unicast (single key) updates App (BGP) update A K ACK to App replication_ factor == 3 => B,C,D KVL KVL B KVL Unicast Lookup Wait forto each responsible replication affected server list _factor server to according replies hash of K C E D KVL All Allof ofb,c,d: B,C,D: Lookup K,ACKs Merge Send V (e.g. append ), Merge L (e.g. delete links if exist ) ; Update local btrees+lists
13 Communication: Unicast (single key) updates App (BGP) update A ACK to App Replication_factor unicast packets (+ACKs) per each key update (or > if KVL chunked) K KVL B UDP + chunking + per-chunk ACK-ing for reliability Per-chunk retransmits at timeouts KVL C E D KVL
14 Communication: Multicast updates App (BGP) update A K ACK to App All 1ofmcast A,E: packet Just to contact N Ignore mcast replication_ affected servers packet based on factor == 3 (still ACKs) B,C,DNheader => B,C,D Mcast + UDP + KV L Mcast addr KVL B,C,D B KVL chunking + perchunkaddresses ACK-ing of for Unicast reliability affected nodes,(acks for quick use unicast) dest filtering KVL Wait for Lookup Single mcast replication responsible packet, _factor server list includes in replies all according to header hash of K affected servers C E D KVL Allof ofb,c,d: B,C,D: All Per-chunk Payload Send retransmits at Lookup K,ACKs Merge timeouts + V (e.g. append ), duplicate Merge LACKs (e.g. ignored delete links if exist ); Update local btrees+lists
15 Multi-key bulk updates (unicast) App (BGP) update A K1 ACK to App K2: E,A,B K1 V L K2 V L K3 V L B K1,K2,K3 (Substantially) C-K1,K3 less K3: A,B,C UDP packets and D-K1 ACKs; improved B throughput E-K2 Lookup responsible Wait for Unicast server list K3 Repack updates replies forrepacked each K into scheduled fromupdates allto each E updates bulk affected affected server per server servers Bulked version: Chunking occurs A getsofk2,k3 independently # K1: B,C,D updated keys C K2 D Retransmits, timeouts etc function All of A,B,C,D,E: equivalently Send ACKsall (for Lookup full bulk update) respective Ks, Mcast+header-based Mergecould Vs, Merge filtering be Ls; Update similarly used local for bulk ops as per single ops btrees+lists
16 Communication: Multi-key (bulk) updates Most times applications have >1 data item available to persist at one time in parallel E.g. a BGP packet updates attributes for several prefixes, withdraws > 1 prefixes, independent packets persisted in parallel etc We optimize such cases via bulk operations: Allow for > data+acks to be in flight in the DHT Less (de-)marshaling, more efficient chunking (independent of # of keys), shorter code paths FTSS has an optimization layer for bulk ops We allow any # of ops for different K s (Value overwrites, Link set links/unlinks etc) to be given in parallel + we group KVL tuples based on dest server + only then subsequent chunking
17 Using KVL Primitive allowing flexibility in optimizing priority ops/building scalable storage Can be used as building block for: Navigational / object DB Centralized or distributed indices over data Write- vs. read-(recovery) optimized Collocating related data together etc Support for complex queries via indexing & distributed key searching
18 Use case: BGP Main inter-domain routing protocol of the Internet ISPs announce to neighbors and further propagate which prefixes they offer routes for (+ attributes) Based on BGP information it collects, an ISP ultimately decides how to route its traffic (=BGP Best Path Selection algorithm)
19 Use case: BGP [2] Basically, changes in Internet routing state are disseminated via BGP peering betw. ISPs (ebgp) and within (ibgp) Info about a prefix: AS_PATH, ORIGIN, MED, NEXT_HOP, COMMUNITY, LOCAL_PREF, WEIGHT etc
20 Use case: BGP [3] Conceptually 2 types of updates (can be bulked together): Prefix withdrawals (== peer doesn t route that prefix at all anymore) Prefix announcements (== only way to update attributes for a given path)
21 Use case: BGP [4] Typically BGP speakers on routers installed on RP node and resets handled via e.g. BGP Graceful Restart (basically full table resynchronized w/ neighbors) ~10 mins At peek (e.g. at some peer s reset), one can see very high update rates (full table ~300K prefixes)
22 Use case: BGP [5] External protocol speakers (e.g. BGP peers) S1 S2 Sn Protocol updates FT frontend (e.g. TCP) layer Protocol updates SHIM App State Checkpoint/Restore Update flow + protocol state summarization FTSS Fast, fault tolerant, malleable online database for generic application state Fail-stop S I B L I N G 1 S I B L I N G 2 S I B L I N G m Paravirtualized, codebaseindependent protocol implementations (~ protocol device drivers ) Byzantine
23 BGP to KVL a simple implementation 1 KVL tuple per each peer PeerEntry 1 per each unique set of attributes AttrEntry Prefixes held as entries in L section of all corresponding AttrEntries 1 recovery index - RootInode
24 BGP to KVL a simple implementation [2] Recovery Index Peer 1 AttrEntry 1 Prefix 1 Peer 2 Peer n AttrEntry 2 Prefix 2 AttrEntry m Prefix p
25 BGP to KVL a simple implementation [3] Recovery Index Peer 1 AttrEntry 1 Pfx Tree Peer 2 Peer n AttrEntry 2 Pfx Tree AttrEntry m Pfx Tree
26 A BGP KVL illustration KVL tuples BGP update ATTRIBUTES Announced Prefx 1 Announced Prefx 2 Announced Prefx n Withdrawn Prefx 1 K1 Meta Keys data K2 ATTR Keys data or Pfxs [ more ATTR KVLs] Withdrawn Prefx 2 Withdrawn Prefx m K Pfx Empty 100 data [ more PFX KVLs] Top inode KVL: holding links to distinct attribute KVLs Attribute KVL: holds in L unique links (or immediate data) to all KVLs of announced paths which have those attributes; attribute data itself is in V Prefix KVL: prefix data + empty links. Alternatively, can be missing altogether: data held as links in respective ATTR KVL.
27 A BGP KVL illustration [2] Given structure, we can translate a BGP update as a number of separate (K,V,L) updates (links, unlinks, data overwrites etc) The bulk update optimizer then repacks updates accordingly per destination As we typically have > key updates than servers, this matters, e.g: 100 updates,5 servers,2 replicas => ~40 updates to be bulked per server
28 Load balancing tuples & links
29 Distributed indexes Implemented as distributed B+trees (B-link trees) We leverage DHT topology maintenance for server pool Attempt to minimize locking/synchronization while: remaining malleable remaining consistent handling DHT routing inconsistencies
30 B-tree
31 Bigger B-tree
32 B-tree Insertion / node split Initial No node split Node split
33 B-tree - Rebalancing Initial No node split Rebalancing
34 B-tree Root split Initial Root split
35 B-tree Delete + (cascade) node merge Initial -60 Node merge
36 B-tree properties Ops are logarithmic (of large base, e.g. ~100 or >) in # keys stored Preserve order Load is balanced among all nodes There are concurrent versions, versions that minimize locking, distributed versions, top-down/single pass splitting, bulk updating etc Structure of choice for DB indexes etc
37 B-tree - DHT specifics / issues B-tree nodes are regular KVL tuples maintained in the DHT => B-tree nodes are replicated Pointers are DHT keys rather than explicit servers; rely on DHT table lookups to resolve Catch: Node views on membership may be inconsistent Our B-tree supports reconfiguration while remaining consistent, with minimum locking; via BNode versioning Our main use case: bulk updates from a single writer => not so much concurrency, but BTree replication+malleability issues
38 Routing inconsistencies B A B A Between steps 3 and 4: RPC K K C D E C F D 1 E A s view of K: C, E, F F B s view of K: 2 D, E, F D is late to answer, A deems it dead B A K C D E 3 F B A A lets everyone know K D died C D E 4 F
39 KVL B-tree node splitting/naming +5 K Vl L v K Vl K:v K:v
40 KVL B-tree node splitting/naming K Vl K:v K Vl K:v V+3 K:v V+5 K:v+2 K:v V V+5
41 Node fields Node Version Sibl Key Left Node Name Last write which passed through node (modifying it or not) Chld Chld Vsn Vsn 1 Sep 2 Sep Val Val Chld Chld 1 2 Key Key 1 2 Parent Key Sibl Key Right At which B-Tree version this node was created Last successful write of child subtree
42 Regular writes & reads V+N K:N2 V+1 V+N K:N1 V+N+1 K V+N Client K:N3 V+1 K:N4 V+6 K:N5
43 Regular writes & reads V+N K:N2 V+1 V+N K:N1 V+N+1 K V+N Client K:N3 V+1 K:N4 V+6 K:N5
44 Regular writes & reads V+N K:N2 V+1 V+N K:N1 V+N+1 K V+N Client V+6 K:N3 V+1 V+1 K:N4 K:N5
45 Regular writes & reads K:N2 V+1 V+N V+N K:N1 V+N+1 K V+N Client V+6 K:N3 V+1 V+1 K:N4 K:N5
46 Internal node split Node needs to split V+N K:N2 V+1 K:N1 V+N V+N+1 K V+N Client V+6 K:N3 V+1 K:N4 K:N5
47 Internal node split Node needs to split V+N K:N2 V+1 K:N1 V+N V+N+1 K V+N Client V+6 K:N3 V+1 K:N4 K:N5 Agree upon some Authoritative Topology Leader election based on it
48 Internal node split AT Node needs to split K:N2 V+N K:N1 V+1 V+N V+N+1 K V+N Client V+6 K:N3 V+1 K:N4 K:N5
49 Internal node split Node needs to split V+N K:N2 V+1 K:N1 V+N V+N+1 K V+N Client V+6 K:N3 V+1 K:N4 V+N K:V+N K:N5
50 Internal node split Node needs to split V+N AT, split val, [recurse] K:N2 V+1 K:N1 V+N V+N+1 K V+N Client V+6 K:N3 V+1 K:N4 V+N K:V+N K:N5
51 Snapshots Some workloads are not optimized for the particular inode indexing structure E.g. BGP DB indexed on AttrEntry, Prefix but RIS bview traces organized on Prefix first (then Peer) Client library includes a snapshoting iface, whereby a snapshot can be built at client, then bulk written
52 Complex queries recover_all ( root_set, inode_range_query, where_query ) root_set = set of inodes to start from inode_range_query = range query on inode, e.g. keys in [K1, K2) where_query = condition on retrieved nodes, e.g. contains_some(key_set) E.g.: recover_all(pfx_inode, [PFX_left, PFX_right], contains_some(as507, AS100)) recover_all(pfx_inode, *, contains_some(appid1, AppID2))
53 Evaluation: FTSS
54 Writes cost per key
55 Writes throughput
56 Writes cost per key
57 Writes scaling in replication factor
58 Writes scaling in replication factor (tpt)
59 Link ops cost per key
60 Link ops throughput
61 Link ops cost per key
62 Link ops scaling in rep. factor
63 Writes effect of bulking (& copy reduction)
64 Evaluation: BGP/FTSS
65 Prefixes per peer distribution
66 Prefixes per peer distribution [2]
67 Internet table growth
68 Processing speed In current implementation above ~ BGP updates /second 1 BGP update = several link/unlink ops, possibly writes/deletes There is further space for improvement via further bulking a/o better load balancing (e.g. node allocation on ring, decentralized recovery index)
69 Load balancing Overall Bytecount
70 Load balancing tuples & links
71 CDF of individual tree load
72 Conclusions FTSS is a fast & malleable persistence layer, suitable for app checkpointing Non-relational, extensible, distributed DB, write-intensive oriented, targeted at persisting real-time processes e.g. BGP
73 Future work Evaluating various complex queries, aggregation, (partial) recovery, BTree indexes Further explore indexing wrt write/read tradeoff, various update patterns etc Models on top of KVL, e.g. object serialization, pointer (un-)swizzling, BigTable-like etc
CS 457 Lecture 19 Global Internet - BGP. Fall 2011
CS 457 Lecture 19 Global Internet - BGP Fall 2011 Decision Process Calculate degree of preference for each route in Adj-RIB-In as follows (apply following steps until one route is left): select route with
More informationBased on Computer Networking, 4 th Edition by Kurose and Ross
Computer Networks Internet Routing Based on Computer Networking, 4 th Edition by Kurose and Ross Intra-AS Routing Also known as Interior Gateway Protocols (IGP) Most common Intra-AS routing protocols:
More informationECSE-6600: Internet Protocols Exam 2
ECSE-6600: Internet Protocols Exam 2 Time: 75 min (strictly enforced) Points: 50 YOUR NAME: Be brief, but DO NOT omit necessary detail {Note: Simply copying text directly from the slides or notes will
More informationBorder Gateway Protocol (BGP)
Border Gateway Protocol (BGP) Petr Grygárek rek 1 Role of Autonomous Systems on the Internet 2 Autonomous systems Not possible to maintain complete Internet topology information on all routers big database,
More informationRoute Discovery Protocols
Route Discovery Protocols Columbus, OH 43210 Jain@cse.ohio-State.Edu http://www.cse.ohio-state.edu/~jain/ 1 Overview Building Routing Tables Routing Information Protocol Version 1 (RIP V1) RIP V2 OSPF
More informationBell Aliant. Business Internet Border Gateway Protocol Policy and Features Guidelines
Bell Aliant Business Internet Border Gateway Protocol Policy and Features Guidelines Effective 05/30/2006, Updated 1/30/2015 BGP Policy and Features Guidelines 1 Bell Aliant BGP Features Bell Aliant offers
More informationExterior Gateway Protocols (BGP)
Exterior Gateway Protocols (BGP) Internet Structure Large ISP Large ISP Stub Dial-Up ISP Small ISP Stub Stub Stub Autonomous Systems (AS) Internet is not a single network! The Internet is a collection
More informationA Transport Protocol for Multimedia Wireless Sensor Networks
A Transport Protocol for Multimedia Wireless Sensor Networks Duarte Meneses, António Grilo, Paulo Rogério Pereira 1 NGI'2011: A Transport Protocol for Multimedia Wireless Sensor Networks Introduction Wireless
More informationSingle Pass Load Balancing with Session Persistence in IPv6 Network. C. J. (Charlie) Liu Network Operations Charter Communications
Single Pass Load Balancing with Session Persistence in IPv6 Network C. J. (Charlie) Liu Network Operations Charter Communications Load Balancer Today o Load balancing is still in use today. It is now considered
More informationNetwork Measurement. Why Measure the Network? Types of Measurement. Traffic Measurement. Packet Monitoring. Monitoring a LAN Link. ScienLfic discovery
Why Measure the Network? Network Measurement Jennifer Rexford COS 461: Computer Networks Lectures: MW 10-10:50am in Architecture N101 ScienLfic discovery Characterizing traffic, topology, performance Understanding
More informationpmacct: introducing BGP natively into a NetFlow/sFlow collector
pmacct: introducing BGP natively into a NetFlow/sFlow collector Paolo Lucente the pmacct project AS286 http://www.pmacct.net/ SwiNOG #19 meeting, Berne, 29 th Sep 2009 pmacct:
More informationIntroduction to TCP/IP
Introduction to TCP/IP Raj Jain The Ohio State University Columbus, OH 43210 Nayna Networks Milpitas, CA 95035 Email: Jain@ACM.Org http://www.cis.ohio-state.edu/~jain/ 1 Overview! Internetworking Protocol
More informationModule 7. Routing and Congestion Control. Version 2 CSE IIT, Kharagpur
Module 7 Routing and Congestion Control Lesson 4 Border Gateway Protocol (BGP) Specific Instructional Objectives On completion of this lesson, the students will be able to: Explain the operation of the
More informationZooKeeper. Table of contents
by Table of contents 1 ZooKeeper: A Distributed Coordination Service for Distributed Applications... 2 1.1 Design Goals...2 1.2 Data model and the hierarchical namespace...3 1.3 Nodes and ephemeral nodes...
More informationIn Memory Accelerator for MongoDB
In Memory Accelerator for MongoDB Yakov Zhdanov, Director R&D GridGain Systems GridGain: In Memory Computing Leader 5 years in production 100s of customers & users Starts every 10 secs worldwide Over 15,000,000
More informationNetwork layer: Overview. Network layer functions IP Routing and forwarding
Network layer: Overview Network layer functions IP Routing and forwarding 1 Network layer functions Transport packet from sending to receiving hosts Network layer protocols in every host, router application
More informationFacebook: Cassandra. Smruti R. Sarangi. Department of Computer Science Indian Institute of Technology New Delhi, India. Overview Design Evaluation
Facebook: Cassandra Smruti R. Sarangi Department of Computer Science Indian Institute of Technology New Delhi, India Smruti R. Sarangi Leader Election 1/24 Outline 1 2 3 Smruti R. Sarangi Leader Election
More informationBGP overview BGP operations BGP messages BGP decision algorithm BGP states
BGP overview BGP operations BGP messages BGP decision algorithm BGP states 1 BGP overview Currently in version 4. InterAS (or Interdomain) routing protocol for exchanging network reachability information
More informationAPNIC elearning: BGP Attributes
APNIC elearning: BGP Attributes Contact: training@apnic.net erou04_v1.0 Overview BGP Attributes Well-known and Optional Attributes AS Path AS Loop Detection ibgp and ebgp Next Hop Next Hop Best Practice
More informationAdapting Distributed Hash Tables for Mobile Ad Hoc Networks
University of Tübingen Chair for Computer Networks and Internet Adapting Distributed Hash Tables for Mobile Ad Hoc Networks Tobias Heer, Stefan Götz, Simon Rieche, Klaus Wehrle Protocol Engineering and
More informationAdvanced BGP Policy. Advanced Topics
Advanced BGP Policy George Wu TCOM690 Advanced Topics Route redundancy Load balancing Routing Symmetry 1 Route Optimization Issues Redundancy provide multiple alternate paths usually multiple connections
More informationLoad balancing and traffic control in BGP
DD2491 p2 2011 Load balancing and traffic control in BGP Olof Hagsand KTH CSC 1 Issues in load balancing Load balancing: spread traffic on several paths instead of a single. Why? Use resources better Can
More informationInternet Protocol: IP packet headers. vendredi 18 octobre 13
Internet Protocol: IP packet headers 1 IPv4 header V L TOS Total Length Identification F Frag TTL Proto Checksum Options Source address Destination address Data (payload) Padding V: Version (IPv4 ; IPv6)
More informationInter-domain Routing Basics. Border Gateway Protocol. Inter-domain Routing Basics. Inter-domain Routing Basics. Exterior routing protocols created to:
Border Gateway Protocol Exterior routing protocols created to: control the expansion of routing tables provide a structured view of the Internet by segregating routing domains into separate administrations
More informationBorder Gateway Protocol BGP4 (2)
Border Gateway Protocol BGP4 (2) Professor Richard Harris School of Engineering and Advanced Technology (SEAT) Presentation Outline Border Gateway Protocol - Continued Computer Networks - 1/2 Learning
More informationInternet Packets. Forwarding Datagrams
Internet Packets Packets at the network layer level are called datagrams They are encapsulated in frames for delivery across physical networks Frames are packets at the data link layer Datagrams are formed
More informationLecture 3: Scaling by Load Balancing 1. Comments on reviews i. 2. Topic 1: Scalability a. QUESTION: What are problems? i. These papers look at
Lecture 3: Scaling by Load Balancing 1. Comments on reviews i. 2. Topic 1: Scalability a. QUESTION: What are problems? i. These papers look at distributing load b. QUESTION: What is the context? i. How
More informationInternet Firewall CSIS 4222. Packet Filtering. Internet Firewall. Examples. Spring 2011 CSIS 4222. net15 1. Routers can implement packet filtering
Internet Firewall CSIS 4222 A combination of hardware and software that isolates an organization s internal network from the Internet at large Ch 27: Internet Routing Ch 30: Packet filtering & firewalls
More informationLecture 18: Border Gateway Protocol"
Lecture 18: Border Gateway Protocol" CSE 123: Computer Networks Alex C. Snoeren HW 3 due Wednesday! Some figures courtesy Mike Freedman Lecture 18 Overview" Path-vector Routing Allows scalable, informed
More informationInternational Journal of Scientific & Engineering Research, Volume 4, Issue 11, November-2013 349 ISSN 2229-5518
International Journal of Scientific & Engineering Research, Volume 4, Issue 11, November-2013 349 Load Balancing Heterogeneous Request in DHT-based P2P Systems Mrs. Yogita A. Dalvi Dr. R. Shankar Mr. Atesh
More informationInternet inter-as routing: BGP
Internet inter-as routing: BGP BGP (Border Gateway Protocol): the de facto standard BGP provides each AS a means to: 1. Obtain subnet reachability information from neighboring ASs. 2. Propagate the reachability
More informationDistributed File Systems
Distributed File Systems Paul Krzyzanowski Rutgers University October 28, 2012 1 Introduction The classic network file systems we examined, NFS, CIFS, AFS, Coda, were designed as client-server applications.
More informationComputer Networks - CS132/EECS148 - Spring 2013 ------------------------------------------------------------------------------
Computer Networks - CS132/EECS148 - Spring 2013 Instructor: Karim El Defrawy Assignment 2 Deadline : April 25 th 9:30pm (hard and soft copies required) ------------------------------------------------------------------------------
More informationAgenda. Distributed System Structures. Why Distributed Systems? Motivation
Agenda Distributed System Structures CSCI 444/544 Operating Systems Fall 2008 Motivation Network structure Fundamental network services Sockets and ports Client/server model Remote Procedure Call (RPC)
More informationCan Forwarding Loops Appear when Activating ibgp Multipath Load Sharing?
Can Forwarding Loops Appear when Activating ibgp Multipath Load Sharing? Simon Balon and Guy Leduc Research Unit in Networking EECS Department- University of Liège (ULg) Institut Montefiore, B28 - B-4000
More informationIP Multicasting. Applications with multiple receivers
IP Multicasting Relates to Lab 10. It covers IP multicasting, including multicast addressing, IGMP, and multicast routing. 1 Applications with multiple receivers Many applications transmit the same data
More informationAPNIC elearning: BGP Basics. Contact: training@apnic.net. erou03_v1.0
erou03_v1.0 APNIC elearning: BGP Basics Contact: training@apnic.net Overview What is BGP? BGP Features Path Vector Routing Protocol Peering and Transit BGP General Operation BGP Terminology BGP Attributes
More informationIP addressing. Interface: Connection between host, router and physical link. IP address: 32-bit identifier for host, router interface
IP addressing IP address: 32-bit identifier for host, router interface Interface: Connection between host, router and physical link routers typically have multiple interfaces host may have multiple interfaces
More information1. Comments on reviews a. Need to avoid just summarizing web page asks you for:
1. Comments on reviews a. Need to avoid just summarizing web page asks you for: i. A one or two sentence summary of the paper ii. A description of the problem they were trying to solve iii. A summary of
More informationRouting Protocols. Interconnected ASes. Hierarchical Routing. Hierarchical Routing
Routing Protocols scale: with 200 million destinations: can t store all dest s in routing tables! routing table exchange would swamp links! Hierarchical Routing Our routing study thus far - idealization
More informationHDFS Users Guide. Table of contents
Table of contents 1 Purpose...2 2 Overview...2 3 Prerequisites...3 4 Web Interface...3 5 Shell Commands... 3 5.1 DFSAdmin Command...4 6 Secondary NameNode...4 7 Checkpoint Node...5 8 Backup Node...6 9
More informationDatagram-based network layer: forwarding; routing. Additional function of VCbased network layer: call setup.
CEN 007C Computer Networks Fundamentals Instructor: Prof. A. Helmy Homework : Network Layer Assigned: Nov. 28 th, 2011. Due Date: Dec 8 th, 2011 (to the TA) 1. ( points) What are the 2 most important network-layer
More informationLoad Balancing and Sessions. C. Kopparapu, Load Balancing Servers, Firewalls and Caches. Wiley, 2002.
Load Balancing and Sessions C. Kopparapu, Load Balancing Servers, Firewalls and Caches. Wiley, 2002. Scalability multiple servers Availability server fails Manageability Goals do not route to it take servers
More informationRouting Protocols (RIP, OSPF, BGP)
Chapter 13 Routing Protocols (RIP, OSPF, BGP) INTERIOR AND EXTERIOR ROUTING RIP OSPF BGP 1 The McGraw-Hill Companies, Inc., 2000 1 Introduction Packets may pass through several networks on their way to
More informationMultihoming and Multi-path Routing. CS 7260 Nick Feamster January 29. 2007
Multihoming and Multi-path Routing CS 7260 Nick Feamster January 29. 2007 Today s Topic IP-Based Multihoming What is it? What problem is it solving? (Why multihome?) How is it implemented today (in IP)?
More informationCassandra A Decentralized, Structured Storage System
Cassandra A Decentralized, Structured Storage System Avinash Lakshman and Prashant Malik Facebook Published: April 2010, Volume 44, Issue 2 Communications of the ACM http://dl.acm.org/citation.cfm?id=1773922
More informationDistributed File Systems
Distributed File Systems Mauro Fruet University of Trento - Italy 2011/12/19 Mauro Fruet (UniTN) Distributed File Systems 2011/12/19 1 / 39 Outline 1 Distributed File Systems 2 The Google File System (GFS)
More informationAnycast Rou,ng: Local Delivery. Tom Daly, CTO h<p://dyn.com Up,me is the Bo<om Line
Anycast Rou,ng: Local Delivery Tom Daly, CTO h
More informationExercises TCP/IP Networking. Solution. With Solutions
Exercises TCP/IP Networking Solution. With Solutions Jean-Yves Le Boudec Fall 2010 Exercises marked with a were given at exams in the past. 1 Module 1: TCP/IP Architecture Exercise 1.1 Elaine is setting
More informationCSE 473 Introduction to Computer Networks. Exam 2 Solutions. Your name: 10/31/2013
CSE 473 Introduction to Computer Networks Jon Turner Exam Solutions Your name: 0/3/03. (0 points). Consider a circular DHT with 7 nodes numbered 0,,...,6, where the nodes cache key-values pairs for 60
More informationPeer-to-Peer and Grid Computing. Chapter 4: Peer-to-Peer Storage
Peer-to-Peer and Grid Computing Chapter 4: Peer-to-Peer Storage Chapter Outline Using DHTs to build more complex systems How DHT can help? What problems DHTs solve? What problems are left unsolved? P2P
More informationBGP Attributes and Path Selection
BGP Attributes and Path Selection ISP Workshops Last updated 29 th March 2015 1 BGP Attributes BGP s policy tool kit 2 What Is an Attribute?... Next Hop AS Path MED...... p Part of a BGP Update p Describes
More informationDirect NFS - Design considerations for next-gen NAS appliances optimized for database workloads Akshay Shah Gurmeet Goindi Oracle
Direct NFS - Design considerations for next-gen NAS appliances optimized for database workloads Akshay Shah Gurmeet Goindi Oracle Agenda Introduction Database Architecture Direct NFS Client NFS Server
More informationA Standard Modest WebSite
A Standard Modest WebSite 3-tier application using Servlets and JDBC HTTP Servlet JDBC JSP...... Servlet DBMS Clients Application Server Roadmap Want to grow to robust enterprise-scale systems: replicated
More informationPETASCALE DATA STORAGE INSTITUTE. SciDAC @ Petascale storage issues. 3 universities, 5 labs, G. Gibson, CMU, PI
PETASCALE DATA STORAGE INSTITUTE 3 universities, 5 labs, G. Gibson, CMU, PI SciDAC @ Petascale storage issues www.pdsi-scidac.org Community building: ie. PDSW-SC07 (Sun 11th) APIs & standards: ie., Parallel
More informationBigData. An Overview of Several Approaches. David Mera 16/12/2013. Masaryk University Brno, Czech Republic
BigData An Overview of Several Approaches David Mera Masaryk University Brno, Czech Republic 16/12/2013 Table of Contents 1 Introduction 2 Terminology 3 Approaches focused on batch data processing MapReduce-Hadoop
More informationBigdata High Availability (HA) Architecture
Bigdata High Availability (HA) Architecture Introduction This whitepaper describes an HA architecture based on a shared nothing design. Each node uses commodity hardware and has its own local resources
More informationCS514: Intermediate Course in Computer Systems
: Intermediate Course in Computer Systems Lecture 7: Sept. 19, 2003 Load Balancing Options Sources Lots of graphics and product description courtesy F5 website (www.f5.com) I believe F5 is market leader
More informationAdvanced Computer Networks. Layer-7-Switching and Loadbalancing
Oriana Riva, Department of Computer Science ETH Zürich Advanced Computer Networks 263-3501-00 Layer-7-Switching and Loadbalancing Patrick Stuedi, Qin Yin and Timothy Roscoe Spring Semester 2015 Outline
More informationLecture 14: Data transfer in multihop wireless networks. Mythili Vutukuru CS 653 Spring 2014 March 6, Thursday
Lecture 14: Data transfer in multihop wireless networks Mythili Vutukuru CS 653 Spring 2014 March 6, Thursday Data transfer over multiple wireless hops Many applications: TCP flow from a wireless node
More informationBGP Terminology, Concepts, and Operation. Chapter 6 2007 2010, Cisco Systems, Inc. All rights reserved. Cisco Public
BGP Terminology, Concepts, and Operation 1 IGP versus EGP Interior gateway protocol (IGP) A routing protocol operating within an Autonomous System (AS). RIP, OSPF, and EIGRP are IGPs. Exterior gateway
More informationAdvanced IPSec with GET VPN. Nadhem J. AlFardan Consulting System Engineer Cisco Systems nalfarda@cisco.com
Advanced IPSec with GET VPN Nadhem J. AlFardan Consulting System Engineer Cisco Systems nalfarda@cisco.com 1 Agenda Motivations for GET-enabled IPVPN GET-enabled IPVPN Overview GET Deployment Properties
More informationCS268 Exam Solutions. 1) End-to-End (20 pts)
CS268 Exam Solutions General comments: ) If you would like a re-grade, submit in email a complete explanation of why your solution should be re-graded. Quote parts of your solution if necessary. In person
More informationDistributed Systems. 23. Content Delivery Networks (CDN) Paul Krzyzanowski. Rutgers University. Fall 2015
Distributed Systems 23. Content Delivery Networks (CDN) Paul Krzyzanowski Rutgers University Fall 2015 November 17, 2015 2014-2015 Paul Krzyzanowski 1 Motivation Serving web content from one location presents
More informationOutline. Failure Types
Outline Database Management and Tuning Johann Gamper Free University of Bozen-Bolzano Faculty of Computer Science IDSE Unit 11 1 2 Conclusion Acknowledgements: The slides are provided by Nikolaus Augsten
More informationCOMP 361 Computer Communications Networks. Fall Semester 2003. Midterm Examination
COMP 361 Computer Communications Networks Fall Semester 2003 Midterm Examination Date: October 23, 2003, Time 18:30pm --19:50pm Name: Student ID: Email: Instructions: 1. This is a closed book exam 2. This
More informationPeer-to-Peer Networks. Chapter 6: P2P Content Distribution
Peer-to-Peer Networks Chapter 6: P2P Content Distribution Chapter Outline Content distribution overview Why P2P content distribution? Network coding Peer-to-peer multicast Kangasharju: Peer-to-Peer Networks
More informationIn-Memory Databases MemSQL
IT4BI - Université Libre de Bruxelles In-Memory Databases MemSQL Gabby Nikolova Thao Ha Contents I. In-memory Databases...4 1. Concept:...4 2. Indexing:...4 a. b. c. d. AVL Tree:...4 B-Tree and B+ Tree:...5
More information6.263 Data Communication Networks
6.6 Data Communication Networks Lecture : Internet Routing (some slides are taken from I. Stoica and N. Mckewon & T. Griffin) Dina Katabi dk@mit.edu www.nms.csail.mit.edu/~dina Books Text Book Data Communication
More informationQuestion 1. [7 points] Consider the following scenario and assume host H s routing table is the one given below:
Computer Networks II Master degree in Computer Engineering Exam session: 11/02/2009 Teacher: Emiliano Trevisani Last name First name Student Identification number You are only allowed to use a pen and
More informationCSC458 Lecture 6. Homework #1 Grades. Inter-domain Routing IP Addressing. Administrivia. Midterm will Cover Following Topics
CSC458 Lecture 6 Inter-domain Routing IP Addressing Stefan Saroiu http://www.cs.toronto.edu/syslab/courses/csc458 University of Toronto at Mississauga Homework #1 Grades Fraction of Students 100 80 60
More informationLoad Balancing. Final Network Exam LSNAT. Sommaire. How works a "traditional" NAT? Un article de Le wiki des TPs RSM.
Load Balancing Un article de Le wiki des TPs RSM. PC Final Network Exam Sommaire 1 LSNAT 1.1 Deployement of LSNAT in a globally unique address space (LS-NAT) 1.2 Operation of LSNAT in conjunction with
More informationE6998-02: Internet Routing
E6998-02: Internet Routing Lecture 13 Border Gateway Protocol, Part II John Ioannidis AT&T Labs Research ji+ir@cs.columbia.edu Copyright 2002 by John Ioannidis. All Rights Reserved. Announcements Lectures
More informationDoing Don ts: Modifying BGP Attributes within an Autonomous System
Doing Don ts: Modifying BGP Attributes within an Autonomous System Luca Cittadini, Stefano Vissicchio, Giuseppe Di Battista Università degli Studi RomaTre IEEE/IFIP Network Operations and Management Symposium
More informationCloud Computing at Google. Architecture
Cloud Computing at Google Google File System Web Systems and Algorithms Google Chris Brooks Department of Computer Science University of San Francisco Google has developed a layered system to handle webscale
More informationInternet Ideal: Simple Network Model
Middleboxes Reading: Ch. 8.4 Internet Ideal: Simple Network Model Globally unique identifiers Each node has a unique, fixed IP address reachable from everyone and everywhere Simple packet forwarding Network
More informationHow To Understand Bg
Table of Contents BGP Case Studies...1 BGP4 Case Studies Section 1...3 Contents...3 Introduction...3 How Does BGP Work?...3 ebgp and ibgp...3 Enabling BGP Routing...4 Forming BGP Neighbors...4 BGP and
More informationIPV6 流 量 分 析 探 讨 北 京 大 学 计 算 中 心 周 昌 令
IPV6 流 量 分 析 探 讨 北 京 大 学 计 算 中 心 周 昌 令 1 内 容 流 量 分 析 简 介 IPv6 下 的 新 问 题 和 挑 战 协 议 格 式 变 更 用 户 行 为 特 征 变 更 安 全 问 题 演 化 流 量 导 出 手 段 变 化 设 备 参 考 配 置 流 量 工 具 总 结 2 流 量 分 析 简 介 流 量 分 析 目 标 who, what, where,
More informationDistributed Data Management
Introduction Distributed Data Management Involves the distribution of data and work among more than one machine in the network. Distributed computing is more broad than canonical client/server, in that
More informationIP Address Classes (Some are Obsolete) 15-441 Computer Networking. Important Concepts. Subnetting 15-441 15-641. Lecture 8 IP Addressing & Packets
Address Classes (Some are Obsolete) 15-441 15-441 Computer Networking 15-641 Class A 0 Network ID Network ID 8 16 Host ID Host ID 24 32 Lecture 8 Addressing & Packets Peter Steenkiste Fall 2013 www.cs.cmu.edu/~prs/15-441-f13
More informationInterdomain Routing. Outline
Interdomain Routing David Andersen 15-744 Spring 2007 Carnegie Mellon University Outline What does the Internet look like? Relationships between providers Enforced by: Export filters and import ranking
More informationMiddleboxes. Firewalls. Internet Ideal: Simple Network Model. Internet Reality. Middleboxes. Firewalls. Globally unique idenpfiers
Ideal: Simple Network Model Middleboxes Jennifer Rexford COS 461: Computer Networks Lectures: MW 10-10:50am in Architecture N101 hgp://www.cs.princeton.edu/courses/archive/spr12/cos461/ Globally unique
More informationbasic BGP in Huawei CLI
basic BGP in Huawei CLI BGP stands for Border Gateway Protocol. It is widely used among Internet Service Providers to make core routing decisions on the Internet. The current BGP version is BGP-4 defined
More informationApplication Layer. CMPT371 12-1 Application Layer 1. Required Reading: Chapter 2 of the text book. Outline of Chapter 2
CMPT371 12-1 Application Layer 1 Application Layer Required Reading: Chapter 2 of the text book. Outline of Chapter 2 Network applications HTTP, protocol for web application FTP, file transfer protocol
More informationRouting Protocol - BGP
Routing Protocol - BGP BGP Enterprise Network BGP ISP AS 3000 AS 2000 BGP is using between Autonomous Systems BGP(cont.) RFC 1771(BGPv4) Support CIDR Transfer the AS information to reach destination Using
More informationOverview. Big Data in Apache Hadoop. - HDFS - MapReduce in Hadoop - YARN. https://hadoop.apache.org. Big Data Management and Analytics
Overview Big Data in Apache Hadoop - HDFS - MapReduce in Hadoop - YARN https://hadoop.apache.org 138 Apache Hadoop - Historical Background - 2003: Google publishes its cluster architecture & DFS (GFS)
More information8. 網路流量管理 Network Traffic Management
8. 網路流量管理 Network Traffic Management Measurement vs. Metrics end-to-end performance topology, configuration, routing, link properties state active measurements active routes active topology link bit error
More informationFaculty of Engineering Computer Engineering Department Islamic University of Gaza 2012. Network Chapter# 19 INTERNETWORK OPERATION
Faculty of Engineering Computer Engineering Department Islamic University of Gaza 2012 Network Chapter# 19 INTERNETWORK OPERATION Review Questions ٢ Network Chapter# 19 INTERNETWORK OPERATION 19.1 List
More informationIAB IPv6 Multi-Homing BOF. Jason Schiller Senior Internet Network Engineer IP Core Infrastructure Engineering UUNET / MCI
IAB IPv6 Multi-Homing BOF Jason Schiller Senior Internet Network Engineer IP Core Infrastructure Engineering UUNET / MCI Multi-homing Problems Inbound to the destination traffic engineering is needed Current
More informationIP Network Layer. Datagram ID FLAG Fragment Offset. IP Datagrams. IP Addresses. IP Addresses. CSCE 515: Computer Network Programming TCP/IP
CSCE 515: Computer Network Programming TCP/IP IP Network Layer Wenyuan Xu Department of Computer Science and Engineering University of South Carolina IP Datagrams IP is the network layer packet delivery
More informationLecture 8: Routing I Distance-vector Algorithms. CSE 123: Computer Networks Stefan Savage
Lecture 8: Routing I Distance-vector Algorithms CSE 3: Computer Networks Stefan Savage This class New topic: routing How do I get there from here? Overview Routing overview Intra vs. Inter-domain routing
More informationThe Sierra Clustered Database Engine, the technology at the heart of
A New Approach: Clustrix Sierra Database Engine The Sierra Clustered Database Engine, the technology at the heart of the Clustrix solution, is a shared-nothing environment that includes the Sierra Parallel
More informationThe Case for Source Address Routing in Multihoming Sites
The Case for Source Address Dependent Routing in Multihoming Marcelo Bagnulo, Alberto García-Martínez, Juan Rodríguez, Arturo Azcorra. Universidad Carlos III de Madrid Av. Universidad, 30. Leganés. Madrid.
More informationPrepared By : Manoj Kumar Joshi & Vikas Sawhney
Prepared By : Manoj Kumar Joshi & Vikas Sawhney General Agenda Introduction to Hadoop Architecture Acknowledgement Thanks to all the authors who left their selfexplanatory images on the internet. Thanks
More informationLoad balancing and traffic control in BGP
DD2491 p2 2009/2010 Load balancing and traffic control in BGP Olof Hagsand KTH /CSC 1 Issues in load balancing Load balancing: spread traffic on several paths instead of a single. Why? Use resources better
More informationEINDHOVEN UNIVERSITY OF TECHNOLOGY Department of Mathematics and Computer Science
EINDHOVEN UNIVERSITY OF TECHNOLOGY Department of Mathematics and Computer Science Examination Computer Networks (2IC15) on Monday, June 22 nd 2009, 9.00h-12.00h. First read the entire examination. There
More informationUnderstanding Virtual Router and Virtual Systems
Understanding Virtual Router and Virtual Systems PAN- OS 6.0 Humair Ali Professional Services Content Table of Contents VIRTUAL ROUTER... 5 CONNECTED... 8 STATIC ROUTING... 9 OSPF... 11 BGP... 17 IMPORT
More informationFirst Midterm for ECE374 02/25/15 Solution!!
1 First Midterm for ECE374 02/25/15 Solution!! Instructions: Put your name and student number on each sheet of paper! The exam is closed book. You have 90 minutes to complete the exam. Be a smart exam
More informationHybrid Overlay Multicast Framework draft-irtf-sam-hybrid-overlay-framework-01.txt. John Buford, Avaya Labs Research
Hybrid Overlay Multicast Framework draft-irtf-sam-hybrid-overlay-framework-01.txt John Buford, Avaya Labs Research Topics SAM Charter Recap and Problem Statement AMT(Automatic Multicast Tunneling) Overview
More informationLecture 5: GFS & HDFS! Claudia Hauff (Web Information Systems)! ti2736b-ewi@tudelft.nl
Big Data Processing, 2014/15 Lecture 5: GFS & HDFS!! Claudia Hauff (Web Information Systems)! ti2736b-ewi@tudelft.nl 1 Course content Introduction Data streams 1 & 2 The MapReduce paradigm Looking behind
More information