Editing Evolution-Data Optimized (section)

=== EV-DO Rev. A (TIA-856 Revision A) ===
Revision A of EV-DO makes several additions to the protocol while keeping it completely backwards compatible with Release 0.

These changes included the introduction of several new forward link data rates that increase the maximum burst rate from 2.45&nbsp;Mbit/s to 3.1&nbsp;Mbit/s. Also included were protocols that would decrease connection establishment time (called enhanced access channel MAC), the ability for more than one mobile to share the same timeslot (multi-user packets) and the introduction of [[Quality of service|QoS]] flags. All of these were put in place to allow for low latency, low bit rate communications such as [[Voice over Internet Protocol|VoIP]].<ref name='Gopal'>{{Cite book| first=Thawatt | last=Gopal| title=2007 IEEE Wireless Communications and Networking Conference| chapter=EVDO Rev. A Control Channel Bandwidth Analysis for Paging| publisher=IEEE| pages=3262–7| date=11–15 March 2007| doi= 10.1109/WCNC.2007.601| isbn=978-1-4244-0658-6| s2cid=15430071}}</ref>

The additional forward rates for EV-DO Rev. An are:<ref name="RevAStandard">{{cite web |url=http://www.3gpp2.org/Public_html/specs/C.S0024-A_v2.0_050727.pdf |title=cdma2000 High Rate Packet Data Air Interface |access-date=2008-01-18 |date=July 2005 |publisher=[[3GPP2]] |pages=10–114 |archive-url=https://web.archive.org/web/20080216101310/http://www.3gpp2.org/Public_html/specs/C.S0024-A_v2.0_050727.pdf |archive-date=2008-02-16 |url-status=dead }}</ref>

{| class="wikitable"
|-
! DRC Index
! [[Bit rate|Data rate in kbit/s]]
! Slots scheduled
! Payload size (bits)
! [[Code rate|Code Rate]]
! [[Modulation]]
|-
| 13
| 1536
| 2
| 5120
| 5/12
| [[QAM#Rectangular QAM|16-QAM]]
|-
| 14
| 3072
| 1
| 5120
| 5/6
| [[QAM#Rectangular QAM|16-QAM]]
|}

In addition to the changes on the forward link, the reverse link was enhanced to support higher complexity [[modulation]] (and thus higher bit rates). An optional secondary pilot was added, which is activated by the mobile when it tries to achieve enhanced data rates. To combat reverse link congestion and noise rise, the protocol calls for each mobile to be given an interference allowance which is replenished by the network when the reverse link conditions allow it.<ref name="RevAStandard" /> The reverse link has a maximum rate of 1.8&nbsp;Mbit/s, but under normal conditions users experience a rate of approximately 500-1000&nbsp;Kbit/s but with more [[Relationship between latency and throughput|latency]] than [[DOCSIS]] and [[DSL]].