Changes

===SIM card===

===SIM card===

Unlike GSM networks, CDMA does not requires a SIM card.  When connecting to a 3G network, a CDMA phone identifies it with a hard-coded identifier (ESN or MEID<ref>http://www.smartmobilephonesolutions.com/content/imei-vs-meid-vs-esn-purpose-of-a-device-identifier</ref>), which is compared by the carrier to a whitelist.  Some CDMA phones will have SIM cards, however, since that is the standard for LTE technology.

Unlike GSM networks, CDMA does not requires a SIM card.  When connecting to a 3G network, a CDMA phone identifies it with a hard-coded identifier (ESN or MEID<ref>http://www.smartmobilephonesolutions.com/content/imei-vs-meid-vs-esn-purpose-of-a-device-identifier</ref>), which is compared by the carrier to a whitelist.  Some CDMA phones will have SIM cards, however, since that is the standard for the newer LTE technology.

<ref>https://www.lifewire.com/definition-of-cdma-578666</ref>

<ref>https://www.lifewire.com/definition-of-cdma-578666</ref>

===3G simultaneous access===

===3G simultaneous access===

Another notable characteristic of many CDMA cell phone systems is that they cannot process voice and data communication at the same time.  A solution to this issue is available, but not always used. Additionally, the speed itself of CDMA 3G communication tends to be slower than that of GSM 3G service.<ref>http://www.wisegeek.org/what-is-the-difference-between-gsm-and-cdma.htm</ref>

Another notable characteristic of many CDMA cell phone systems is that they cannot process voice and data communication at the same time.  A solution to this issue is available, but not always used. Additionally, the speed itself of CDMA 3G communication tends to be slower than that of GSM 3G service.<ref>http://www.wisegeek.org/what-is-the-difference-between-gsm-and-cdma.htm</ref>