Network Neutrality 4/21/20111Harvard Bits

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Because most Americans only have a choice of only one or two broadband carriers, carriers are tempted to impose a toll charge on content and services, discriminating against websites that are unwilling to pay for equal treatment. This could create a two-tier Internet in which websites with the best relationships with network providers can get the fastest access to consumers, while all competing websites remain in a slower lane. Such a result would threaten innovation, the open tradition and architecture of the Internet, and competition among content and backbone providers. It would also threaten the equality of speech through which the Internet has begun to transform American political and cultural discourse. Barack Obama supports the basic principle that network providers should not be allowed to charge fees to privilege the content or applications of some web sites and Internet applications over others. 4/21/2011Harvard Bits3

McCain does not believe in prescriptive regulation like ‘net- neutrality,’ but rather he believes that an open marketplace with a variety of consumer choices is the best deterrent against unfair practices. [Government should] leave consumers free to access the content they choose; free to use the applications and services they choose; free to attach devices they choose, if they do not harm the network; and free to chose among broadband service providers. Net neutrality legislation could be counterproductive and actually harm the openness of the Internet. 4/21/2011Harvard Bits4

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Common Carriers 4/21/2011Harvard Bits6

Common Carriers 4/21/2011Harvard Bits7

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Common Carriers Nondiscrimination Regulation Price controls Interference with free market 4/21/2011Harvard Bits9

Telegraph 4/21/2011Harvard Bits10

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Should the Internet Be A Common Carrier? What does the question even mean? Core vs. Edge ISPs – Comcast -> Cable TV – Verizon -> Telephone Who owns the Core? 4/21/2011Harvard Bits12

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Core vs. Edge Intelligence at the edge – Higher level protocols – Cryptography – Innovative services Dumb routers and links comprise the core – Internet protocol – Just pass the packets along a link – Best effort So who has the money-making opportunities? 4/21/2011Harvard Bits17

Vertical Integration Western Union – AP formed a vertically integrated business partnership Content provider and content carrier Comcast? Verizon? Control of the carrier by the content provider doesn’t sound like a great idea, but They laid the wires! Don’t they have the most to gain from innovation? 4/21/2011Harvard Bits18

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How Could Carriers Discriminate? Sometimes they HAVE to drop a packet Buffer is full: Which packet do I drop? – Incoming packet – Least favorite packet, to make space 4/21/2011Harvard Bits21

Ways to Discriminate Against Low-Priority Packets ? First to drop if buffer overflows ? Drop whenever network utilization exceeds X% of capacity ? Push them to the back of the queue ? Simply delay them unnecessarily 4/21/2011Harvard Bits22

Impact of Dropped or Delayed Packets Irregular flow rate causes jitter at destination Essentially no impact: – – Web pages – Recorded Video (YouTube, etc. – latency irrelevant) 4/21/2011Harvard Bits23 Bursty inputSteady output Buffer

Impact of Dropped or Delayed Packets Significant impact – Real-time voice, Voice over IP (VOIP) – Skype – Online games 4/21/2011Harvard Bits24

How Could You Tell Whether a Carrier is Discriminating? Is perceived jitter an engineering problem or a policy decision? Can be very hard to judge from outside – just as it is hard to judge whether racial and gender disparities are intentional discrimination! 4/21/2011Harvard Bits25

How Does the Internet Avoid the Tragedy of the Commons? 4/21/2011Harvard Bits26

Tragedy of the Commons, Internet Style TCP detects when packets are dropped Voluntarily decreases rate at which packets are injected into the network If nobody did this Internet would break down If everybody does this it works great 4/21/2011Harvard Bits27

Tragedy of the Commons, Internet Style If ALMOST everybody does this, it STILL works great 4/21/2011Harvard Bits28

Would Encryption Help Avoid Traffic Management? Suppose we wanted to use VOIP but avoid detection Encrypting the packets makes it harder to tell they are VOIP Takes time at both ends Pattern of packet flow can still be revealing ISP could still decide to introduce random delay for all packets 4/21/2011Harvard Bits29

What About Quality of Service? QoS = guaranteed bit rate Objection to NN: May prevent ISP from offering higher quality service for higher prices In practice: – If there is enough bandwidth in the network, service turns out to be fine – If there is not enough bandwidth, no QoS guarantees can help 4/21/2011Harvard Bits30

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