The Abdus Salam International Centre for Theoretical Physics SCHOOL ON RADIO USE FOR DIGITAL AND MULTIMEDIA COMMUNICATIONS (11 February - 1 March 2002)

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Presentation transcript:

The Abdus Salam International Centre for Theoretical Physics SCHOOL ON RADIO USE FOR DIGITAL AND MULTIMEDIA COMMUNICATIONS (11 February - 1 March 2002) IP Technology: History, Current State, Prospective Gennady G. Yanovsky St. Petersburg State University of Telecommunications, St. Petersburg, Russia

IP-Technology: History, Current State, Prospective 1. Brief History of the Internet 2. IP Traffic 3. What is IP Technology? 4. What is INTERNET? 5. How Does IP Work? 6. Why use IP? 7. Key Factors of Internet Evolution 8. New Version IP - IPv6 9. Quality of Service (QoS) in INTERNET 10. IP Telephony

1957 – Launch of Sputnic is impetus for U.S. to form ARPA (DoD) 1965 – ARPA sponsors a study “Cooperative network for time-sharing”; Innovation of packet switching (D. Devis, UK, P. Baran, US) 1969 – September 2, launch of first computer network ARPANET 1972 – Beginning of (Tomlinson, US) 1974 – First article about TCP/IP (Cerf/Kahn) 1979 – Establishing first research computer network (NSF, Univ. Wisc., DARPA) Continued… 1. Brief History of the Internet

1982 – Internet defined as TCP/IP-connected networks 1986 – 56 kb/s NSFNET created for 5 supercomputing centers 1989 – Number of Internet nodes breaks ; IETF comes into existence 1992 – WWW released; Number of nodes breaks 1M 1995 – Internet Society was founded VoIP comes to the market 2000 – Number of hosts breaks 300M 2002 – VoIP has taken away 13% of long-haul telephone traffic

The Internet Timeline Military/Academic Apps Commercial Apps

Forecast of Subscribers’ Number in Telephone Fixed and Mobile Networks and in Internet Source: Ericsson, 1999 MU IU FU No. of Subscribers, mln

Penetration (in %) of Different Technologies and Devices Mobile penetration Internet penetration PC penetration Broadband Penetration USA Europe Asia << 5 17 <5 <30 <<<5 Source: Cisco, 2002

2. IP Traffic

Forecast of the global voice/data traffic’s growth Total telephone traffic International telephone traffic Data traffic Tbps Source: Arthur D. Little, 1999

U.S. Internet IP Traffic Growth (Based on Report provided by Lawrence G. Roberts, Chairman & CTO and Cindy Crump, Director Research, Caspian Networks) Following analysis represents the first real measurements of Internet traffic since 1996

Perceived Decline in Internet Growth Many analysts, equipment vendors maintain Internet traffic has been declining –Internet growth has “already begun a relentless process of slowing” – JP Morgan H&Q/McKinsey –“Internet traffic is down for the first time in history” – John Roth, Nortel Networks –Has the Net Stopped Growing? [feature article] – The Industry Standard

Why This Belief? IP service providers’ capital shortage and margin shortfall Vendors report lower sales Despite these points, Caspian Networks’ measurements show that IP traffic growth is not slowing

IP Traffic Growing Faster Than Ever IP service providers: – Bought extra equipment in 2000 – Are improving equipment utilization – Are fighting for market share Will have to start buying again soon Will buy equipment to keep up with traffic growth The following analysis represents the first real measurements of Internet traffic since 1996

IP Backbone Topology Edge Router Trunk Ports Edge Router Interconnect Ports Edge Ports Core Router Trunk Ports Core Router

Total U.S. Internet Traffic Voice Crossover: August /Year 2.8/Year 1Gbps 1Tbps 10Tbps 100Gbps 10Gbps 100Tbps 100Mbps 1Kbps 1Mbps 10Mbps 100Kbps 10Kbps 100 bps 1 Pbps 100 Pbps 10 Pbps 10 bps ARPA & NSF Data to 1996 New Measurements Projected at 4/Year Source: Roberts et al., 2001

Why Has The Growth Rate Increased? Most traffic is from corporations (80% estimated) –Main growth is from corporations –“Last mile” has been improving rapidly (100–1000 Mbps) –Corporate traffic is anti-recessionary Move from private networks to Internet for cost reduction Continued...

– Corporate Internet use hit critical mass in 2000 Now need to use the Internet for all business Inter-corporate traffic is now mainly over the Internet Intra-corporate traffic is growing in size ( documents) Personal traffic is growing but broadband deployment is slow Internationally, traffic is still at the pre-2000 growth rate of 2.8/year

Communications Switching Equipment Market $ M per Year ,000 10, , Market Timing Packet Analog TDM Switching equipment sales must grow with IP traffic Equipment price decreased 37%/year Source: Roberts et al., 2001

Traffic measurements: Concluding remarks Internet traffic growth rate increased from 2.8 to 4 per year in 2000 –Traffic over measured period doubled every 6 months Internet traffic continued to grow at 4 per year through Q The main traffic source, corporate traffic, is anti-recessionary Continued…

Service providers have serious problems - They can only avoid equipment purchases for a short period - They must buy equipment soon to hold market share Assuming traffic keeps doubling every 6 months: - Optical and IP switching equipment purchases must also grow at 4x - If IP service prices continue to fall at 2x, service provider’s IP revenue will grow at 2x and IP service revenue will then exceed voice revenue in about 2–3 years Traffic measurements: Concluding remarks

3. What is IP Technology? (Position of IP Among Other Forwarding Techniques)

3.1. IP - Internet Protocol and the IETF Model Physical Data Link Network Transport Application IP

Definition of Internet Protocol Network Layer Protocol (Layer 3) Protocol Data Unit (PDU) is Packet End-to-End Addressing (Source and Destination) Connectionless-oriented Protocol “Best Effort” Service – Provides unreliable packet delivery services

Switching Technologies CS PSTN FR 1970th IP Х.25 MS Tlg. Net. ATM 1980th Connection-oriented networks Connectionless-oriented networks PS 1960th

What is the “Switch” Switches Packet Circuit Two Main Classes Source: Telecommunications Research Association, TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Samples of Circuit Switches Source: TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Layer 2 Layer 3 (older protocols, X.25) Layer 3 and Above Switches Routers Taxonomy of Packet Switching Source: TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Layer 2 Layer 3 (older protocols, X.25) Layer 3 and Above Switches Routers WAN LAN Token Ring FRATM Ethernet Layer 2 Switching Technologies Source: TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Layer 2 Layer 3 (older protocols, X.25) Layer 3 and Above Switches Routers WAN LAN Token Ring FRATM Ethernet Software Forwarding Large Set of Protocols Hardware Forwarding Smaller Set of Protocols SW or HW-based Routers Source: TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Layer 2 Layer 3 (older protocols, X.25) Layer 3 and Above Switches Routers WAN LAN Token Ring FRATM Ethernet Software ForwardingHardware Forwarding IP Router Source: TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Layer 2 Layer 3 (older protocols, X.25) Layer 3 and Above Switches Routers WAN LAN Token Ring FRATM Ethernet Software ForwardingHardware Forwarding IP Router Layer 3 Switch Layer 4 Switch Source: TRA, 2000

What is the “Switch” Switches Packet Circuit Tandem & Toll Local Layer 2 Layer 3 (older protocols, X.25) Layer 3 and Above Switches Routers WAN LAN Token Ring FRATM Ethernet Software ForwardingHardware Forwarding IP Router Layer 3 Switch Layer 4 Switch Full Routing Procedures on Every Packet Routing Shortcuts IP Switch Source: TRA, 2000

Summary of Switches’ Taxonomy Switch – Layer 2 (LAN, FR, ATM) Router – Traditional Layer 3, SW-based IP router Layer 3 Switch – HW-based Router IP Switch – HW-based Router with Shorted Routing Layer 4 Switch – HW-based Router with some Elements of Layer 4 for QoS

3.2. TCP – Transmission Control Protocol and the IETF Model Physical Data Link Network Transport Application TCP

TCP – Transmission Control Protocol Transport Layer (Layer 4) Is processed in endpoints Connection-oriented protocol Provides flow control and adapts to a network congestion

4. What is INTERNET? (Draft definition) (Generally) A collection of thousands of networks Based on the TCP/IP suite With no central policy-making/regulatory body Based on technical specs developed by Internet Engineering Task Force (IETF) and called Request for Comments (RFCs) Using single address space Provides for users on any one of the networks to communicate or use the services located on any of the other networks

5. How Does IP Work? IP - Internet Protocol Packet Structure - Header & Data - Variable Length - Not predictable IP Addressing

IP Header

IP Addressing - Numeric Addressing - Symbolic Addressing - Domain Name and Domain Name Service (DNS) - URL DNS Server Internet User Internet Server Source: James Cavanagh, Global telecommunications Consultant, GTC, Lecture Notes, 2000

IP Addressing IP Numeric Addressing Dotted Decimal Notation IP Classfull Addressing - Classes A,B,C,D & E

Two-level addressing – networks/devices Number of possible addresses Devices - PC - Servers - Routers Class A – big networks (BNs) Address – 8 bits Number of BNs – mln devices per network Total amount of devices ~2 bln IP Numeric Addressing

Class B – medium networks (MNs) Address – 8 bits Number of MNs –16, thousands devices per network Total amount of devices ~1bln Class C – small networks (SNs) Address – 24 bits Number of SNs –1,097, devices per network Total amount of devices ~500 mln Class D – for multicast communications Class E – for different kind of testing

Class Addresses А - 1.ххх.ххх.ххх ххх.ххх.ххх В ххх.ххх ххх.ххх С ххх ххх D Note: ххх from 0 to 255

Symbolic Addressing (Domain Form) ictp.trieste.it com – commercial (for-profit enterprise) edu – educational (educational facility) mil – military (military body) net – network (network facility or service provider) gov – government (body or agency of a government entity org – organization (entity, which does not fall clearly into any mentioned categories)

Domain Name and Domain Name Service Domain Name locates an organization or other entity on the Internet. DNS is a way that Internet domain name are translated addresses into numeric Internet protocol address. DNS is based on the number DNS servers. Universal Resource Locator URL is the address of a file (resource) accessible on the Internet. URL contains a name of a protocol required to access the resource, domain name that identifies a specific computer on the Internet, and hierarchical description of the file location on the computer

How Does IP Work? DNS Server Internet User Internet Server Peering Point Source: James Cavanagh, GTC, Lecture Notes, 2000

Some Definitions (www. isoc.org) Internet Society is an international non-profit organization that acts as a guide and conscience for working of the Internet. It was founded in 1992 and based in Reston, Virginia organizations, 6000 individuals in over 170 countries - standards, public policy, training and education, membership activities

IETF - Internet Engineering Task Force, is the body that defines standard Internet operating protocols such as TCP/IP. IETF is supervised by Internet Society IAB. Standards are expressed in the form of RFCs. IETF is large open international community of network designers, vendors, operators and researchers IAB - Internet Architecture Board, is a technical advisory group of Internet society. IAB is an overseer of the technical evolution of the Internet and IAB supervises IETF

ICANN - Internet Corporation for Assigned Names and Numbers (former IANA) is a private (non-government) corporation with responsibility for - IP address space allocation - protocol parameters assignment - domain name system management - rout server system management RFC - Request for Comments is a formal document from IETF that is result of committee drafting and subsequent review by interested parties. The final version of RFC becomes the standard and no further comments or changes are permitted.

6.Why use IP? Key Features of IP Technology A. Universality Used: - In all network segments - For transport data, voice, video - In fixed/mobile networks - In public and corporate networks Continued…

The “Generic” Network Model Premise (PCE) Access Segment Backbone or Core Network “The Cloud” Source: James Cavanagh, GTC, Lecture Notes, 2000

IP’s Role in the Network Premise LAN/Desktop Campus Backbone Access Low Speed (56/64) Medium Speed (E1) High Speed (>E1 to SDH) Integrated Access Backbone Voice Data Video Multimedia Source: James Cavanagh, GTC, Lecture Notes, 2000

Putting IP to Work Voice Delay Delay Variation Loss VBD / FAX Data Delay Delay Variation Loss Video Delay Delay Variation Loss Multimedia Delay Delay Variation Loss Source: James Cavanagh, GTC, Lecture Notes, 2000

B. Scalability - Allows to combine a great number of networks (number of nodes, hosts and users) C. Openness - Open protocol platform - Networks’ interoperability - Simple protocol stack (TCP/IP) - Availability of specifications Key Features of IP Technology Continued…

IP Characteristics “Best Effort” Protocol Reliability via Higher Layers Used with TCP and UDP

Why use IP? - Wide Acceptance Internet Popularity Global Reach - IP Standards Mature Standards Interoperability - IP Protocol Characteristics Simple Protocol Good General Purpose Protocol

IP’s Perfect Applications Internet Intranet Extranet

Intranet is a private network that is contained within an enterprise. It may consist of many interlinked LANs and also use WANs. Typically, Intranet includes connections through one ore more gateway computers to the outside Internet. The main purpose of an Intranet is to share company’s information and computing resources among employees. An Intranet uses TCP/IP, HTML and other Internet protocols and in general looks like a private version of the Internet. One of the main problem in communications via public network is to provide the required level of security

Extranet is a private network that uses the Internet protocols and the public telecom system to securely share a part of a business information with suppliers, vendors, partners and customers. Extranet can be considered as a part of company’s Intranet that is extended to users outside the company. interlinked LANs and also use WANs. An Extranet requires security and privacy and it uses the same tools as Intranet - firewall servers, users authentication, encryption and also VPNs

7. Key Factors of Internet Evolution New regulations in telecommunications - Open markets, grows of competition, globalization - Alternative operators - New service providers New technologies - Grows of network’s capacity (CNs - FOT, SDH, DWDM; ANs – Gigabit Ethernet, xDSL) - Progress in microprocessors’ productivity (Moore Law) - New mechanisms and protocols Market requirements - Grows of users - Commercialization of Internet - Development of customized applications

Model of Service Waves (Development of IP Networks) FW – Dial-up access SW – VoIP TW – New services (FoIP, Call Centers, CTI) FW – Multiservice IP-based networks

Challenges of IP Using as a Base for Multiservice Network Solution Capacity - Access networks - Core networks Quality of service (QoS) - Best Effort Principle (is suitable for , FTP, Web services) Information security’s problems in commercial networks (Heterogeneous WANs) Lack of addresses

8. New Version IP - IPv6 Total length – 320 bits Source address – 128 bits Destination address – 128 bits New mechanisms of security – IPsec New mechanisms of QoS Support of RT services

9. Quality of Service (QoS) in INTERNET Definition of QoS 1. The performance specification of a communications channel or system 2. A subjective rating of telephone communications quality in which listeners judge transmissions by qualifiers, such as excellent, good, fair, poor or unsatisfactory The Glossary of the Telecommunications Term, U.S. Federal Standard 10377

New mechanisms for guaranteed QoS - IntServ (hard mechanisms) - RSVP (Resource reSerVation Protocol) DiffServ (soft mechanisms) – 1998 Level of QoS Best effort IntServ DiffServ

Resource Reservation Protocol A signaling protocol between IP hosts and routers Host request QoS Router either accept or deny the request Routers give priority to traffic with higher QoS - PASS (TSpec) - RESV (RSpec) - Admission control - Policy control

Differentiated Services Based on DS field (delay, losses, capacity) : Type of Service field (IPv4) or Traffic Class field (IPv6) SLA - Service Level Agreement - a service contract between customer and service provider

Main Mechanisms of DiffServ Traffic profile (rate and bust size) Classification (sorting packets on the content of headers Policing (handling out-of profile traffic, e.g. discarding some packets) Shaping (delaying packets for confirming to defined traffic profile) Scheduling (buffer mechanisms) Admission control - a decision process regarding request for possible network resources

10. IP Telephony 1995 – SW VocalTec Independent from distance – low cost Low quality Current state Effective voice coding New services (FoIP, Videoconferences, Universal Messaging, Call Centers) New mechanisms of QoS Standardization

H.323 – Standards for Multimedia Communications Over IP Networks “Umbrella” standard, references other standards and ITU recommendations Intended for data, voice and video communications H.323 Components: Terminal Gateway Gatekeeper Multipoint Control Unit (MCU)

H.323 components Intranet/ Internet (IP Network) Intranet/ Internet (IP Network) Router Gatekeeper H.323 Terminals Router Gateway (Voice IWU) PSTN/ ISDN PSTN/ ISDN ATM PBX H.323 Terminals Gatekeeper Gateway (Voice IWU) Source: R. Koch, G.Yanovsky, Evolution and Convergence in Telecommunications, book, published in 2001

H.323 Terminal Client endpoins on the network Must support audio 64 kb/s, 8, 6.2, 5.3 kb/s Video, data support is optional H.323 Gateway Support interoperability with other terminal types Provides translation functions between H.323 and circuit- switched networks (PSTN): Transmission formats Signaling procedures Audio/video transcoding

H.323 Gatekeeper Admission coding for the network Bandwidth control and management Address translation (PSTN Address IP Address) Manages all terminals, Gatewways, MCUs in H.323 area H.323 MCU Support conference between 3 or more endpoints Mixes, switches and processes media streams May be located in Terminal, Gateway or Gatekeeper

PSTN/ISDN Network scenarios for Voice-over- IP (VoIP) Call Processing Name Server OAM Server (Gatekeeper) RAS POP PSTN/ISDN Internet 64 kbit/s speech Voice over IP, e.g. G723.1 Message interface to central server PC to Phone Phone to Phone Phone to PC PC to PC Voice Voice IWU (Gateway) RAS POP Voice IWU (Gateway) MGCP S0urceS0urce Destination Source: R. Koch, G.Yanovsky, Evolution and Convergence in Telecommunications, book, published in 2001

Voice-over-IP - Phone-to- Phone PSTN/ISDN VoIP Server (Gatekeeper) RAS POP PSTN/ISDN Internet Voice Voice IWU (Gateway A) RAS POP Voice IWU (Gateway B) Basic Call "Phone-to-Phone"  A-Subscriber dials IWU E.164 number  Normal Call Setup (a) between A-Subscriber and A-IWU  Announcement from A-IWU to user  Input of A-Subscriber E.164 Number, PIN and B-Subscriber E.164 Number (via multi- frequency code)  H.323 call setup (b) within the Internet between A-IWU and B-IWU (routing function in gatekeeper)  Normal Call Setup (a) between B-IWU and B-Subscriber. AB A B MGCP (a)(b) (a) Source: R. Koch, G.Yanovsky, Evolution and Convergence in Telecommunications, book, published in 2001

Voice-over-IP - PC-to-Phone PSTN/ISDN VoIP Server (Gatekeeper) RAS POP PSTN/ISDN Internet Voice Voice IWU (Gateway) RAS POP Voice IWU (Gateway) Basic Call "PC-to-Phone"  PC needs VoIP software (e.g. H.323)  Normal Internet login (a) of A-Subscriber  Access to VoIP Server  Input PIN and B-Subscriber E.164 Number  H.323 call setup (b) within the Internet between A-subscriber and B-IWU (routing function in gatekeeper)  Normal Call Setup (a) between B-IWU and B-Subscriber. (b) (a) A B A B Source: R. Koch, G.Yanovsky, Evolution and Convergence in Telecommunications, book, published in 2001

Voice-over-IP - Phone-to-PC PSTN/ISDN VoIP Server (Gatekeeper) RAS POP PSTN/ISDN Internet Voice Voice IWU (Gateway) RAS POP Voice IWU (Gateway) Basic Call "Phone to PC"  PC needs VoIP software (e.g. H.323)  Normal Internet login (a) of B-Subscriber and registration at gatekeeper (E.164 to IP address mapping)  A-Subscriber dials IWU E.164 number  Normal Call Setup (a) between A-Subscriber and A-IWU  Input of A-Subscriber E.164 Number, PIN and B-Subscriber E.164 Number H.323 call setup  H.323 call setup (b) within the Internet between A-IWU and B-subscriber PC (routing function and address mapping in gatekeeper) MGCP (a) (b ) A B A B Source: R. Koch, G.Yanovsky, Evolution and Convergence in Telecommunications, book, published in 2001

Concluding Remarks Questions

Thank you!