The Huawei B311-221 is a popular 4G/LTE Cat.6 router, often used as a home or office backup connection, or as primary internet in rural areas. It supports carrier aggregation (2CA), has two external antenna ports, and Wi-Fi 802.11 b/g/n. Many users buy it second-hand or from mobile carriers (Vodafone, T-Mobile, EE, Telstra, etc.), which lock it to a specific network. Unlock firmware refers to modified or patched firmware that removes this SIM lock, allowing the router to work with any carrier.
Caution and recommendations:
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