ECEN5553 Telecom Systems Dr. George ScheetsWeek #5 Read [7c] "How can the Internet have too many routes and not enough addresses?" [8a] "The Cognitive Net is Coming" [8b] "The Internet of Things" [9a] "Browse at your Own Risk" [9b] "The Data Brokers: Selling Your Personal Information" [10a] "Internet QoS: Pieces of the Puzzle" [10b] "Innovation on the Web Lives and Dies with Net Neutrality" Exam #1 Lecture 16, 24 September (Live) No later than 1 October (Remote DL) Outline 8 October 2014, Lecture 22 (Live) No later than 15 October (Remote DL)

Outlines Received due 8 October (local) 15 October (remote) 22 %

Exam #1 (90 points) Exam #1 (90 points) n Friday, 24 September (Local) Remote Distant Learners, no later than 1 October n Work 3 of 4 pages n Closed Book & Notes n Calculators & phones are NOT allowed...Set up numerical problem for full credit n Most equations are provided (on 5th page) n Approximately 40% of upcoming exam will be lifted from the Fall 2013 Exam #1 n Anything in the notes, on Power Point, or in reading assignments is fair game

On Short Answer or Essay Questions n Answer the Question! n Memory Dump in the space provided u Knowledgeable individual can write more u Grader will look for "Power Point bullets" u Same remarks as instructor's typically not required n To get "A" or "B", instructor needs to walk away with impression you could've said more u Got space? Anything else pertinent to add? u It is NOT necessary to write small or fill up allotted space to get a good score! u Lost points? No comments? → Insufficient info provided u Rule of Thumb: "X" point question needs > "X" facts

The Internet n VAST collection of interconnected networks n Key Building Block: Routers running IP (Layer 3) n Router link speeds range up to 100 Gbps n Hierarchical Alpha-Numeric Names

AT&T 1997 Internet Backbone

UUNET 1998 Internet Backbone

Washington D.C. Area

OSU 2009 Internet Connectivity

Traceroute to n 4 Internal OSU-Stillwater routers n 3 OneNet routers (all in OKC? Tulsa?) n 2 Qwest routers dal-edge-18.inet.qwest.net n 2 NTT routers ae-19.r08.dllstx09.us.bb.gin.ntt.net n Akamai Technologies (Hosting Service) n (12:55 pm, 11Sept14, rtt = 9 msec, 11 routers)

Traceroute to n 4 Internal OSU-Stillwater routers n 3 OneNet routers (Tulsa?) n 5 Cogent Communications routers u te ccr01.tul01.atlas.cogentco.com u be2128.ccr21.den01.atlas.cogentco.com u be2126.ccr21.slc01.atlas.cogentco.com n 2 Ace Data Center routers (Hosting Service) u ve15.ar05.prov.acedc.net n End server ( ) probably in Provo, Utah area n (1:20 pm, 11Sept14, rtt = 60 msec, 14 routers)

ISP Routes Sometimes Roundabout Launched 13 September 2014, 2 miles from OSU campus n n 1 Scheets' home router n n 4 AT&T routers u u adsl dsl.okcyok.sbcglobal.net u u ggr3.dlstx.ip.att.net n n 4 Cogent Communications routers u u Be2032.ccr22.dfw01.atlat.cogentco.com u u te rcr12.okc01.atlas.cogentco.com n n 3 ONENET routers u u OKC? n 3 Oklahoma State routers n (12:30 pm, 11Sept14, rtt = 84 msec, 15 routers)

Fall 2007 Weird TraceRoute Seen by Student Tulsa to OSU Stillwater n Tracert launched from Tulsa, hit Atlanta Washington, D.C. Illinois Kansas City Tulsa Oklahoma City OSU Stillwater

Internet Service Provider Backbone Switched Network, full duplex trunks. Access lines attach to corporate routers & routers of other ISP's. Router Trunks Access Line

OSU Backbone Access lines attach to Ethernet switches, Onenet and other routers. Router Trunks Access Line

ISO OSI Seven Layer Model n Layer 7 Application n Layer 6 Presentation Windows API n Layer 5 Session Windows TCP n Layer 4 Transport Windows TCP n Layer 3 Network Windows IP n Layer 2 Data Link PC NIC n Layer 1 Physical PC NIC

Internet Protocal v4 (20 Bytes) TOS TTL Source Address Destination Address 4 Bytes

Microsoft's Tracert

802.3 Ethernet Packet Format MAC Destination Address MAC Source Address CRCData + Padding Bytes: IPv4TCP

IPv4 Header n Contains two addresses u 4B Source Address u 4B Destination Address u 4B = 32b = G potential addresses n Example address u n Dotted Decimal Format simplifies u x.x.x.x u Treat each byte as Base2 number, write in Base10 u Above number simplifies to

IP Header n Alpha-numeric name simplifies further u es302.ceat.okstate.edu u Domain Name Servers convert to numerical n All OSU Stillwater addresses are of form u to n IP addresses & alpha-numeric names are effectively backwards u mapped to es302.ceat.okstate.edu

IP vs Ethernet Addresses IP vs Ethernet Addresses nEnEnEnEthernet has a flat address space uSuSuSuSimilar to Social Security Number FAFAFAFAdjacent #'s nearby or on other side of globe? uHuHuHuHuge look up tables required to avoid flooding FNFNFNFNeed trillion entries nInInInIP has a hierarchical address space uPuPuPuPacket delivery similar to Mail delivery FAFAFAFAdjacent IP addresses frequently nearby uRuRuRuReduces size of look up tables FDFDFDFDon't need billion entries

ISP Router Overload Source: 1 October 2007 Network World Fall 2011 Level3 BGP entries 375,550 IPv4 7,210 IPv6 Peak Traffic 8.0 Tbps IPv4 500 Mbps IPv6

ISP Router Overload n Core BGP entries as of 19 August 2014 u IPv4 about 520,400 u IPv6 about 18,300 n 2nd week of August u Caused some problems u Some routers had 512,000 entry limit source: bgp.potaroo.net Network World, 13Aug2014, "Internet outages expected to abate as routers are modified, rebooted"

TCP Header Source PortDestination Port Sequence Number ACK Number Window Checksum 4 Bytes

Wireshark Packet Capture n This interaction starts with a click on a Firefox bookmark to a distance calculator. Firefox then triggers a query to an OSU Domain Name Server asking for the IPv4 address of This is next followed by a TCP 3 way handshake to open logical connections, an HTTP request to download the distance calculator page, and the beginning of the file transfer.

ISO OSI Seven Layer Model n Layer 7 Application n Layer 6 Presentation Windows API n Layer 5 Session Windows TCP n Layer 4 Transport Windows TCP n Layer 3 Network Windows IP n Layer 2 Data Link PC NIC n Layer 1 Physical PC NIC MSS = 1460 B = Size of Layer 6 & 7 info per packet Ethernet Payload = 1500 B

TCP Window Size (Layer 4) Effects End-to-End Throughput n Suppose u Window Size (set by PC) = 64 KB F Microsoft Windows XP u Maximum Segment Size = 1 KB u Server can send < 64 unACK'd packets Server PC 3,000 Km

Throughput on 64 Kbps Line Server PC 3,000 Km, 64 Kbps line n NPD = Prop Delay / Packet inject time u Prop Delay = distance / EM energy speed = 3,000,000 m / 200,000,000 m/sec = seconds u Packet inject time = 8,376 bits / 64 Kbits/sec = seconds (7B PPP, 20B IPv4, 20B TCP) u NPD = / = u Front end of packet arrives at far side prior to back end being transmitted. Packet #1

Throughput on 64 Kbps Line Server PC 3,000 Km, 64 Kbps line n At this instant in time... u 2nd unACK'd packet is being transmitted u ACK for #1 enroute back to server F TCP+IP+Layer 2 → 47 bytes if PPP u When ACK#1 arrives at server, only packet #2 is unacknowledged. n Will 64 packet unACK'd limit be reached? u No. At most, 1 packet likely unACK'd. Packet #2 #1 #1 ACK

Throughput on 45 Mbps Line Server PC 3,000 Km, 45 Mbps line n NPD = Prop Delay / Packet inject time u Prop Delay = distance / EM energy speed = 3,000,000 m / 200,000,000 m/sec = seconds u Packet inject time = 8,376 bits / 45 Mbits/sec = μseconds (PPP, IPv4, TCP overhead) u NPD = / = u average sized packets will fit back-to-back on this line #1#2#3

Throughput on 45 Mbps Line Server PC 3,000 Km, 45 Mbps line n At this instant in time, the Server... u Has transmitted 64 packets w/o ACK. u Has hit window limit. Halts. Packets

Throughput on 45 Mbps Line Server PC 3,000 Km, 45 Mbps line n At this instant in time, u The PC has processed 1st packet & sent an ACK u The Server is still halted, waiting for ACK #1. F When ACK #1 arrives, server can then transmit one additional packet. F Other ACK’s arrive fast enough to allow back-to- back transmission of next group of 64 packets Packets #1 ACK#1

Can Estimate Throughput with a Time Line time t o = 0 n t o : Leading edge of 1st packet injected n t 1 : Trailing edge of 64th packet injected u t 1 = (64*1047B)(8b/B)/(45 Mb/sec) = msec n t 2 : Leading edge of 1st packet hits far side u 15 msec (propagation delay) u If ACK injected right away... n t 3 :...ACK arrives at server at t = 30 msec n Process Repeats... t1t1 t2t2 t3t3

Can Estimate Throughput with a Time Line time (msec) t o = 0 n This system can transmit u 64(1,047) = 67,008 B = 536,064 bits u Every 30 msec (one round trip time) u Estimated throughput = 536,064/0.03 = Mbps n Actual throughput a bit lower u 1st ACK not transmitted until packet #1 fully received... F... and processed by PC u 65th packet not transmitted until ACK #1 fully received... F... and processed by Server

Can Estimate Throughput with a Time Line time (msec) t o = 0 n Need to be able to fill the pipe for 1 RTT u 30 msec in our example u 45 Mbps *.030 sec = 1.35 M b = 168,750 B = 168,750/1,047 = packets u Window Size needs to be = segments*1,000 bytes/segment = 161,200 B n Actually would need another segment or two to cover source & sink processing

TCP Header Source PortDestination Port Sequence Number ACK Number Window Checksum 4 Bytes

UDP Header (8 Bytes) Source PortDestination Port Checksum 4 Bytes For interactive real-time traffic, usually used with Real Time Transport Protocol (12 bytes).

Virtual Circuits n Routing decisions made once when circuit is set up u Concerned switches have internal Look-Up tables updated n All packets part of info transfer follow the same path n Allows option of setting aside switch resources (buffer space, bandwidth) for specific traffic flows n MPLS, Frame Relay, ATM, & Carrier Ethernet use VC’s

Datagrams n IP uses Datagrams n Routing Tables updated independently of individual traffic flows u Routers continuously talking with each other u Packets may follow different paths n Routers get no advance warning of specific packet flows.

IP is Connectionless Data + Padding up to 1,460 IPTCP I/O decisions based on IP address & look-up table. Tables updated independent of traffic, hence path thru network may suddenly change. TCP is connection oriented.

TCP, UDP, and IP n 30+ year old Protocols Designed for data One Priority & “Best Effort” services No QoS Guarantees Available bandwidth depends on other users n TCP (Layer 4 & 5) provides reliable transfer n UDP (Layer 4 & 5) unreliable transfer n IP at Layer 3 n Arbitrary Protocols at Layers 1 & 2

Internet Traffic Comparison source:

Fixed Access Internet Traffic Profile Source: Sandvine_Global_Internet_Phenomena_Snapshot_2H_2012_NA_Fixed.pdf &

2012 Mobile Access Internet Traffic Profile Sandvine_Global_Internet_Phenomena_Snapshot_2H_2012_NA_Mobile.pdf

2013 Mobile Access Internet Traffic Profile source:

Internet Traffic Growth source: "The Road to 100G Deployment", IEEE Communications Magazine, March 2010

Internet Traffic Growth source:

Combining the Figures

VoIP  PC to PC  Internet Phone to Internet Phone Commodity Internet

VoIP  PC to Wired Phone  Internet Phone to Wired Phone Commodity Internet Gateway Phone System

VoIP (Wired Phone-to-Wired Phone)  Carrier prioritizes VoIP traffic (DiffServ)  Paths nailed down (MPLS)  Gateways control # of voice calls  Good Quality Possible with this configuration "QoS Enabled" Internet Gateway Phone System Gateway Phone System

Traditional Videoconferencing Camera Codec 384 Kbps fixed rate output (video + audio) Codec Audio Video Dedicated Bandwidth Network: Circuit Switched TDM times/sec *State Owned Fiber *ISDN

2002 Non-Traditional Videoconferencing Camera Codec 384 Kbps fixed rate output (video + audio) Now > 784 Kbps Codec Audio Video Packet Switched StatMuxed Prioritized *State Owned Fiber This is technique being used in this class for video to & from Tulsa & Stillwater.

Internet Video Streaming PC Disk Drive The Internet Quality of Received Stream depends on: (1) Size of your pipe. (2) Internet congestion. (3) Server congestion.

Internet Video Streaming Stillwater Video Server generates packets. Fairly steady generation if server not swamped. Rate depends on pipe size. Disk Drive

Internet Video Streaming Disk Drive Internet Video Server Packets exit at an irregular rate. Random delays. Non-Dedicated Bandwidth (Packet Switched, Stat Muxing)

ISP Routes can be Roundabout Launched 30 January 2007, 2 miles from OSU campus n n 1 Dr. Scheets' home router n n 6 SBC routers u u adsl dsl.okcyok.sbcglobal.net u u ex2-p11-0.eqchil.sbcglobal.net n n 7 Level3 routers u u Te-3-2.Chicago1.Level3.net u u kscymo2wcx010-pos9-0-oc48.wcg.net u u tulsok6wcx2-pos11-0-oc48.wcg.net n n 5 ONENET routers u u at least 1 in Oklahoma City n 3 Oklahoma State routers Using DiffServe, End-to-End performance on this 22 router path...

ISP Routes can be Roundabout Launched 5 September 2008, 2 miles from OSU campus n n 1 Scheets' home router n n 4 SBC routers u u adsl dsl.okcyok.sbcglobal.net u u bb1-g1-0-2.rcfril.sbcglobal.net n n 1 Equinix router n n 1 Transitrail router u u onenet.chcgil01.transitrail.net n n 3 ONENET routers u u at least 1 in Oklahoma City n 4 Oklahoma State routers n rtt = 55 msec...may be worse than End-to-End performance on this 14 router path when not using DiffServ.

LAN Internet Service Provider Network Router Trunks Leased Line PC Corporate sites using Internet as WAN. Can pay ISP extra $$ → Traffic between sites gets preferential treatment.

Interactive VOICE & VIDEO over the commodity INTERNET (Best Effort, No Priorities) n Is not ready for Prime Time n Delay & Quality problems difficult to solve under the current system... n...although throwing Bandwidth at the problem will alleviate n Has a place for the user whose main concern is $$$$ or convenience

LAN Internet Service Provider Network Routers operate at Layers 1-3. PC’s operate at Layers 1-7. Routers do not monitor opening of TCP Logical Connections. RSVP would change this. Router Trunks Leased Line PC

Multi-Protocol Label Switching n Enables Virtual Circuits u End-to-End Paths nailed down u Traffic Engineering Easier u Resource Reservation Easier n Seeing fairly widespread ISP deployment

Internet QoS n Most every ISP is installing or testing one or more of following... u DiffServ u MPLS u Resource Reservation capability u Pricing structure to reflect different QoS... but they are not yet widely deployed. n As a result, currently the Commodity Internet remains mostly u Best Effort, FIFO Routing

Thinking of moving large amounts of high quality, time sensitive traffic over the Commodity Internet? Check back in 2-3 years when... n Priorities Enabled (IPv6 and/or DiffServ) n Resources Guaranteed (Resource Reservation Protocol (RSVP) or equivalent is deployed) n Flat rate pricing is gone

The Internet Is...  A superb information source  Sometimes difficult to separate wheat from chaff  IEEE Communications or Proceedings  Peer Reviewed  IEEE Spectrum  Reviewed by editor  Jane Doe's Web site  Reviewed by Jane Doe  A good marketing tool

The Internet Is... a Security Nightmare  Any-to-Any connectivity is both strength and weakness  Tracert yields Router IP Addresses  Could Telnet or HTTP to many. Password?  Espionage  Read “The Cuckoo’s Egg” by Cliff Stoll  Former #1 on New York Times Best Seller  Recommended by Dr. Scheets’ Mom