Best Practices Phase Review Template

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<ul><li> 1. Peer-to-Peer SIP Telephony Christian Stegh,N. America Practice Leader, Emerging Technology and IP Telephony VoIP Roundtable2/14/2007 [email_address] 312-634-2404 one # 2006 AvayaInc. All rights reserved.</li></ul> <p> 2. Agenda </p> <ul><li>Why P2PSIP is hot </li></ul> <ul><li>Tutorial of basic concepts </li></ul> <ul><li>Review of open issues </li></ul> <ul><li>Introducing one-X Quick Edition </li></ul> <p>DRAFT UNTIL LAUNCH 3. Household P2P Names </p> <ul><li>Napster</li></ul> <ul><li>BitTorrent </li></ul> <ul><li>Kazza </li></ul> <ul><li>Skype </li></ul> <p>Each is an island unto itself, using proprietary algorithms &amp; signaling protocols. 4. Why P2PSIP? </p> <ul><li>No need for a centralized server </li></ul> <ul><li><ul><li>Phones self-organize into a telephony network and connect to the outside via a simple IP/PSTN gateway or SIP trunk. </li></ul></li></ul> <ul><li>Cost savings: </li></ul> <ul><li><ul><li>No need for central equipment lowers capital expense </li></ul></li></ul> <ul><li><ul><li>The operating cost to install &amp; maintain, and add users to the system is also low because no administration is necessary </li></ul></li></ul> <ul><li><ul><li>Inexpensive calling for consumers across the Internet </li></ul></li></ul> <ul><li>Redundancy in telephony architectures </li></ul> <ul><li>Rapid turn-up time: After plugging the phone into a LAN and entering the users name into it, youre ready to call. </li></ul> <p> 5. No need for centralized server </p> <ul><li>Location information about the called party is kept within the endpoints themselves rather than in a server </li></ul> <ul><li>Peers know about one another directly or by sharing information with other peers in the network </li></ul> <ul><li>When a caller doesnt know the exact location of the party it wants to call, it asks other network peers that are closer to the callee </li></ul> <p> 6. P2PSIP </p> <ul><li>A suite of communication protocols that extend SIP to use peer-to-peer techniques for looking up and reaching users and resources. </li></ul> <p>vs. Typical SIP P2PSIP 7. Redundancy in telephony architectures </p> <ul><li>P2P networks allow the work to be distributed evenly across peers </li></ul> <ul><li>As peers leave perhaps suddenly due to a crash work is again redistributed </li></ul> <ul><li>All nodes are working all the time and as such, standard telephony network infrastructure can become more robust by leveraging P2P </li></ul> <ul><li>One node can backup anothers voicemail service </li></ul> <p> 8. Standards Bodies Support is Swelling </p> <ul><li>IETF Birds of Feather groups started last year </li></ul> <ul><li>Groups size increases at each meeting </li></ul> <ul><li>Numerous drafts have been submitted to the SIPPING (Session Initiation Protocol Project INvestiGation) workgroup </li></ul> <ul><li>P2P SIP is not yet an official work item within the IETF,but there is adraft charter </li></ul> <p> 9. Tutorial of basic concepts 10. Basics </p> <ul><li>P2P layer = distributed database </li></ul> <ul><li>In Real Time Communications, data items stored are mostly information about a user </li></ul> <ul><li><ul><li>Name </li></ul></li></ul> <ul><li><ul><li>IP address of phone </li></ul></li></ul> <ul><li><ul><li>Etc. </li></ul></li></ul> <ul><li>Requirements for a P2P layer for Real-Time Communication (RTC) are not the same as the requirements for file sharing </li></ul> <p> 11. P2P Layer </p> <ul><li>The P2P layer is effectively a replacement for the registration, location, and lookup steps of a SIP server </li></ul> <ul><li>It handles three things: </li></ul> <ul><li><ul><li>How to register a phone or a user with the P2P overlay network (when the phone or user joins the network) </li></ul></li></ul> <ul><li><ul><li>How to lookup a phone or a user in the P2P overlay network (when a call to the phone or user is made </li></ul></li></ul> <ul><li><ul><li>How to dynamically shift information when peers join and leave, so that the load is balanced across peers and so the sudden loss of one or more peers doesnt cause the network to lose track of its current registrants </li></ul></li></ul> <p> 12. Finding Peers </p> <ul><li>At the heart of the P2P algorithm is an efficient way to search for and retrieve information about the location of peers in the overlay network. </li></ul> <ul><li>In small networks, all peers know each other </li></ul> <ul><li>In large networks, too much memory would be required </li></ul> <ul><li><ul><li>Distributed Hash Tables are the answer </li></ul></li></ul> <p> 13. Distributed Hash Tables </p> <ul><li>A DHT is a structured way of organizing the P2P network so that every peer only knows about some of the peers in the network.</li></ul> <ul><li>More efficient than knowing about all peers, </li></ul> <ul><li>A peer can quickly find out about another by asking other network users.</li></ul> <ul><li>When a user tries to call a peer that is not in its table, it queries other peers, which quickly return the location to the user. </li></ul> <p> 14. Popular DHTs include </p> <ul><li>Pastry </li></ul> <ul><li>Tapestry </li></ul> <ul><li>Chord - the basis for some early P2P SIP work </li></ul> <p>Since there are already many methods and moreemerging, DHTs will likely take some time to standardize. 15. Chord </p> <ul><li>Uses a ring structure for the nodes in the overlay </li></ul> <ul><li>Each node is assigned a unique ID and keeps a database of IDs ofsomeof the nodes in the network </li></ul> <ul><li>When a user searches for a node that is not in its own table, the node nearest to the destination address is contacted </li></ul> <ul><li>The nearby node either returns the location of the callee or it sends the request to a node closer to the destination </li></ul> <ul><li>Efficiently minimizes lookup table sizes </li></ul> <p> 16. Routed queries like Chord N 4 Publisher Client N 6 N 9 N 7 N 8 N 3 N 2 N 1 Lookup(title) Key=title Value=MP3 data Without more advanced algorithms, # of hops would be linear to # of peers 17. The Chord algorithm Scalable node localization </p> <ul><li>Each node maintains </li></ul> <ul><li><ul><li>Finger table </li></ul></li></ul> <ul><li><ul><li><ul><li>Entryiin the finger table ofnis the first node that succeeds or equalsn+ 2 i </li></ul></li></ul></li></ul> <ul><li><ul><li>Predecessor node </li></ul></li></ul> <ul><li>Search in finger table for the node that most immediatley precedes id </li></ul> <ul><li>Invoke find_successorfrom that node </li></ul> <ul><li><ul><li>Guarantees that a file is found in O(log( N )) steps </li></ul></li></ul> <p> 18. Standards Debate </p> <ul><li>DHT algorithms continue to be refined </li></ul> <ul><li>But a bigger philosophical difference among early works needs resolution: </li></ul> <ul><li><ul><li>Should the P2P protocol be integrated into SIP by adding new headers? </li></ul></li></ul> <ul><li>Or </li></ul> <ul><li><ul><li>Should it be a separate and distinct layer?</li></ul></li></ul> <p> 19. P2PSIP vs. File-sharing Can be high Low(especially wireline) Join/Leave frequency Can be frequent Infrequent -- not a significant portion of a phones workload Lookups Can be large Small Size of dataitems Can be &gt;&gt; # of nodes # of nodes # of data items P2P layer for File-sharing P2P layer for RTC 20. Enterprise vs. Consumer </p> <ul><li>See (at least) two distinct applications ofP2P-SIP </li></ul> <ul><li>Consumer telephony: Skype-like </li></ul> <ul><li>Enterprise telephony: PBX systems for enterprises </li></ul> <ul><li>These two applications have different requirements </li></ul> <p> 21. Enterprise vs. Consumer 10,000 peers is a small network 10,000 peers is a large network Scale -- Authentication is not so important -- Preventing rogue behavior is important. </p> <ul><li>- Authentication (Can this phone/group join the network?) is very important. </li></ul> <ul><li>- Preventing rogue behavior not so important. </li></ul> <p>Trust Model Artificial? Natural groups (office, division, etc) that a P2P layer should respect. Hierarchy Consumer Enterprise 22. Merging non-P2P clients into the Model SIP UA A UA Peer E UA Peer D Proxy Peer P Redir Peer R Peer Q Gateway Peer G UA Peer F NAT NAT UA Client C P2PSIP Overlay with peersspeaking Peer protocol P2PSIP Client Protocol 23. Sample Message Flow </p> <ul><li>Client calling a Peer: </li></ul> <ul><li>Client C sends a query to Peer Q for the location of User U. </li></ul> <ul><li>Messages are exchanged between peers, and User U is determined to reside on Peer F </li></ul> <ul><li>Peer Q sends response back to Client C. </li></ul> <ul><li>Client C sends SIP Invite message to Peer F. </li></ul> <p>SIP Invite UA Peer E UA Peer D Proxy Peer P Redir Peer R Peer Q Gateway Peer G UA Peer F NAT NAT UA Client C P2PSIP Overlay with peersspeaking Peer protocol P2PSIP Client Protocol 24. Some Design Questions </p> <ul><li>Peer vs Client Protocol:Are these the same things, or not? Do we really need a Client protocol? Are either SIP? </li></ul> <ul><li>How to find a media relay? Does it have to be network-path optimal? </li></ul> <ul><li>How best to arrange NAT traversal? </li></ul> <ul><li>Security: If peers are untrusted, how do we protect sensitive messages flowing through them? </li></ul> <ul><li>Credentials. Certs from a CA? Self-signed? </li></ul> <ul><li>Bootstrapping. How to start from zero? </li></ul> <p> 25. Small Office Challenges Very Small Business Answer:Quick Edition 2.0 Very Small Business </p> <ul><li>No local tech support, limited technical knowledge </li></ul> <ul><li>Need solutions that can easily grow with the business </li></ul> <ul><li>Communications must be completely reliable and secure </li></ul> <ul><li>Costly moves, adds and changes </li></ul> <ul><li>More home and remote workers </li></ul> <p>Branches </p> <ul><li>No local tech support, limited technical knowledge </li></ul> <ul><li>Managing branches is a real headache </li></ul> <ul><li><ul><li>Different systems / vendors </li></ul></li></ul> <ul><li><ul><li>Ability to manage </li></ul></li></ul> <ul><li><ul><li>Communications must be completely reliable and secure </li></ul></li></ul> <ul><li>Costly moves, adds and changes </li></ul> <ul><li>More home and remote workers </li></ul> <p> 26. Avaya one-X Quick Edition Release 2.0Intelligent Communications for the Smallest Office </p> <ul><li>IP Telephony for Small offices </li></ul> <ul><li><ul><li>SIP-based peer-to-peer technology, no centralized hardware </li></ul></li></ul> <ul><li><ul><li>Voicemail, auto-attendant, call processing etc all in the phone </li></ul></li></ul> <ul><li>Dramatically simple, cost effective, productive </li></ul> <ul><li><ul><li>Default install in minutes, customize as required </li></ul></li></ul> <ul><li>Release 2.0 delivers </li></ul> <ul><li><ul><li>SIP Trunking, Multisite Provisioning Tool, QOS, Call Park, Page and Retrieve, Teleworker </li></ul></li></ul> <p> 27. Award Winning Solution If you are looking for lightning-fast setup and zero maintenance, Avaya one-X Quick Edition should be at the top of your list.Co-recipient of 2006 Best in VoiceCon award, based on attendee votes INTERNET TELEPHONY Magazine2006 TMC Labs Innovation Award Winners InfoWorld Test Centers top rating 28. Avaya one-X Quick Edition Release 2.0P2PSIP Attributes </p> <ul><li>Simple </li></ul> <ul><li><ul><li>Set up and make calls in minutes, customize as required </li></ul></li></ul> <ul><li><ul><li>Server-less configuration reduces acquisition costs, TCO </li></ul></li></ul> <ul><li>Cost effective </li></ul> <ul><li><ul><li>Reduce number of trunk lines </li></ul></li></ul> <ul><li><ul><li>Commonly used features built into the phone </li></ul></li></ul> <ul><li><ul><li>Centralized management reduces maintenance costs </li></ul></li></ul> <ul><li>Connected </li></ul> <ul><li><ul><li>Designed for Branches, or Very Small Business </li></ul></li></ul> <ul><li><ul><li>Enterprise wide dial plans drive efficiency </li></ul></li></ul> <ul><li><ul><li>Leverage internet infrastructure while maintaining voice quality </li></ul></li></ul> <p> 29. Standalone Configuration 2006 AvayaInc. All rights reserved. Avaya Proprietary. Not For Distribution. Use pursuant to Company instructions. WAN LAN MultisiteProvisioning Tool Teleworker HTTPS P2P/SIP Quick Edition Branch SIPService Provider G10 Gateways PSTN Peer-to-peer discovery, setup 30. Branch ConfigurationWAN 2006 AvayaInc. All rights reserved. Avaya Proprietary. Not For Distribution. Use pursuant to Company instructions. PSTN WAN LAN MultisiteProvisioning Tool Converged Communication Server, SIP Enablement Services Communication Manager SIP Teleworker HTTPS SIP P2P/SIP G10 Gateways HQ Branch Quick Edition Branch Peer-to-peer discovery, setup 31. Quick Edition Teleworker WAN Internet VPN VPN Ext 202 Ext 200 Ext 201 Ext 204 Ext 203 Ext 202 Ext 201 Ext 200 Ext 203 Ext 204 1.The Quick Edition teleworker feature provides Quick Edition functionality to remote workers of local Quick Edition sites Teleworker over Internet (VPN)Teleworker over WAN2.Teleworker is a mode of operation in the 4610 and 4621 phones which allows Quick Edition to have presence as part the local site dial plan via a VPN or WAN connection 3.VPN connectivity over the Internet is provided by VPN routers which provide for secure LAN access to the branch 5.The VPN router is only required to route IP unicast traffic to/from the LAN and remote connection 4.Teleworker mode removes the dependency of IP multicast traffic which is required for operation on the local LAN 8.This same VPN router can be used to provide data connectivity for a PC to the local network if desirable 6.The teleworker phone can then be moved to/from the remote location and the local branch with the retention of all settings, voicemail, with backup while in transition 7.Standard call forwarding rules can also be applied to direct calls from an internal office phone for off-hours or virtual office day transparency Teleworker Teleworker 32. Features </p> <ul><li>PBX system for small-med organization </li></ul> <ul><li>Is P2P; no central component.</li></ul> <ul><li><ul><li>Phones cooperate to produce PBX functionality </li></ul></li></ul> <ul><li>Supports many standard PBX features: </li></ul> <ul><li><ul><li>Call forward, call transfer, conference call, etc. </li></ul></li></ul> <ul><li><ul><li>Corporate directory (built automatically) </li></ul></li></ul> <ul><li><ul><li>Even features like voicemail, auto attendant, call logs, etc. are done in a distributed fashion. </li></ul></li></ul> <ul><li><ul><li>Seewww.nimcatnetworks.comfor list of features </li></ul></li></ul> <p> 33. Features (cont.) </p> <ul><li>Designed for resiliency - system still works if some phones become unavailable. </li></ul> <ul><li>Designed to be very plug-and-play </li></ul> <ul><li><ul><li>For basic operation, the only configuration required is to enter your name on your phone. </li></ul></li></ul> <ul><li>Two ways to connect to outside world </li></ul> <ul><li><ul><li>Through anoptionalPSTN gateway box (TTI) </li></ul></li></ul> <ul><li><ul><li>Though a SIP service provider </li></ul></li></ul> <p> 34. Implementation </p> <ul><li>Uses SIP for signaling </li></ul> <ul><li>Uses a simple proprietary P2P layer </li></ul> <ul><li><ul><li>Uses multicast to locate peers and join overlay </li></ul></li></ul> <ul><li><ul><li>Uses both multicast and unicast to distribute info about each phone </li></ul></li></ul> <ul><li><ul><li>Each phone has complete knowledge of other phones </li></ul></li></ul> <ul><li>Uses various proprietary schemes for distributing services in the P2P environment </li></ul> <p> 35. More information </p> <ul><li> </li></ul> <ul><li> </li></ul> <ul><li> </li></ul> <ul><li> </li></ul>