Editing Quality of service (section)

==Limitations==
[[Strong cryptography]] network protocols such as [[Transport Layer Security|Secure Sockets Layer]], [[I2P]], and [[virtual private network]]s obscure the data transferred using them.  As all [[electronic commerce]] on the Internet requires the use of such strong cryptography protocols, unilaterally downgrading the performance of encrypted traffic creates an unacceptable hazard for customers. Yet, encrypted traffic is otherwise unable to undergo [[deep packet inspection]] for QoS.

Protocols like [[Independent Computing Architecture|ICA]] and [[Remote Desktop Protocol|RDP]] may encapsulate other traffic (e.g. printing, video streaming) with varying requirements that can make optimization difficult.

The [[Internet2]] project found, in 2001, that the QoS protocols were probably not deployable inside its [[Abilene Network]] with equipment available at that time.<ref name="failure">{{cite web |url= http://qbone.internet2.edu/papers/non-architectural-problems.txt |url-status= dead |title= Why Premium IP Service Has Not Deployed (and Probably Never Will) |author= Benjamin Teitelbaum, [[Stanislav Shalunov]] |date= May 3, 2002 |publisher= Internet2 QoS Working Group |work= Draft Informational Document |archive-url= https://web.archive.org/web/20020830051015/http://qbone.internet2.edu/papers/non-architectural-problems.txt |archive-date= August 30, 2002 |access-date= October 15, 2011 }}</ref>{{efn|Equipment available at the time relied on software to implement QoS.}} The group predicted that "logistical, financial, and organizational barriers will block the way toward any bandwidth guarantees" by protocol modifications aimed at QoS.<ref name="Oram">{{cite web |author=Andy Oram |title= A Nice Way to Get Network Quality of Service? |work= Platform Independent column |archive-url= https://web.archive.org/web/20020805003256/http://www.oreillynet.com/pub/a/network/2002/06/11/platform.html |archive-date= August 5, 2002 |url= http://www.oreillynet.com/pub/a/network/2002/06/11/platform.html |url-status=live |date= June 11, 2002 |publisher= O'Reilly |access-date= October 15, 2011 }}</ref>
They believed that the economics would encourage network providers to deliberately erode the quality of best effort traffic as a way to push customers to higher priced QoS services. Instead they proposed over-provisioning of capacity as more cost-effective at the time.<ref name="failure"/><ref name="Oram"/>

The Abilene network study was the basis for the testimony of Gary Bachula to the [[United States Senate Committee on Commerce, Science and Transportation|US Senate Commerce Committee]]'s hearing on [[Network Neutrality]] in early 2006. He expressed the opinion that adding more bandwidth was more effective than any of the various schemes for accomplishing QoS they examined.<ref>{{cite web |author=Gary Bachula |title=Testimony of Gary R. Bachula, Vice President, Internet2 |url=http://commerce.senate.gov/pdf/bachula-020706.pdf |pages=2–3 |date=February 7, 2006 |access-date=October 15, 2011 |archive-url=https://web.archive.org/web/20100107181546/http://commerce.senate.gov/pdf/bachula-020706.pdf |archive-date=January 7, 2010 |url-status=dead }}</ref> Bachula's testimony has been cited by proponents of a law banning quality of service as proof that no legitimate purpose is served by such an offering. This argument is dependent on the assumption that over-provisioning isn't a form of QoS and that it is always possible. Cost and other factors affect the ability of carriers to build and maintain permanently over-provisioned networks.{{citation needed|date=July 2020}}