<p> An AirCard is a type of wireless <a href="https://www.lifewire.com/what-is-a-modem-817861" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">modem</a> used for connecting mobile devices to the internet through <a href="https://www.lifewire.com/networking-cell-phones-and-wireless-modems-817461" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="2">cellular networks</a>. AirCards provide roaming access to the internet from laptop computers that are outside the range of <a href="https://www.lifewire.com/use-your-cell-phone-as-a-wi-fi-hotspot-2377756" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="3">Wi-Fi hotspots</a>. They can also be used as an alternative to home <a href="https://www.lifewire.com/dial-up-internet-service-over-wireless-816544" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="4">dial-up</a><a href="https://www.lifewire.com/dial-up-internet-service-over-wireless-816544" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="5"> internet service</a> in rural areas or other areas without internet service. They require a contract with a cellular provider, or the service may be bundled with your existing cellular coverage.</p><h3>Types of AirCards</h3><p>Several manufacturers produce <a href="https://www.lifewire.com/wireless-computer-networking-816540" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="6">wireless network</a> modems. Cellular network service providers typically bundle and sometimes rebrand compatible wireless modems with their service contracts. In the U.S., for example, both AT&amp;T and Verizon utilize products from Sierra Wireless even though these may be called &#34;AT&amp;T AirCard&#34; and &#34;Verizon AirCard.&#34;</p><p>AirCard wireless modems come in three standard form factors and they require a compatible port or slot on a laptop to function properly.</p><ul><li>PCMCIA PC Card - the original standard cellular modem card for computers</li><li>ExpressCard - provides a dramatic increase in bandwidth over the PCMCIA card it replaced</li><li><a href="https://www.lifewire.com/universal-serial-bus-816265" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="7">USB</a> modem - provides cellular connectivity to any computer with a USB port</li></ul><p>Wireless modems implement one or more of the common cellular network protocols, often either the <a href="https://www.lifewire.com/ev-do-internet-access-818320" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="8">EV-DO</a> or <a href="https://www.lifewire.com/about-high-speed-downlink-packet-access-577596" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="9">HSDPA</a> / <a href="https://www.lifewire.com/high-speed-packet-access-817467" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="10">HSPA protocols</a>.</p><h3>AirCard Speeds</h3><p>AirCards support much higher data rates than do dial-up connections. While many AirCards offer up to 3.1 Mbps data rate for downloads and up to 1.8 Mbps for uploads, newer USB cellular modems reach 7.2 Mbps down and 5.76 Mbps up. Even though typical AirCard data rates achievable in practice are much lower than these theoretical maximums, they still far exceed the throughput of a dial-up connection.</p><h3>Cons of Using AirCards for Internet Connectivity</h3><p>Unfortunately, AirCards tend to suffer from high <a href="https://www.lifewire.com/latency-on-computer-networks-818119" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="11">network latency</a> that is sometimes even higher than that of a dial-up connection. Expect to experience sluggishness and slow response times when loading web pages over an AirCard connection. Network games are usually unplayable on AirCards for this reason. AirCards cannot compete with the overall performance levels of <a href="https://www.lifewire.com/digital-subscriber-line-817527" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="12">DSL</a> or cable broadband Internet connections.</p>