Upstream bandwidth. Downstream bandwidth

ADSL (Asymmetric Digital Subscriber Loop) technology is an asymmetric digital subscriber line to realize broadband access to the Internet . As a transmission layer technology, ADSL makes full use of existing copper wire resources to provide Upstream 640kbps (theoretically 1Mbps) downlink 8Mbps bandwidth, thus overcoming the "bottleneck" of traditional users in the " last mile " and realizing broadband access in the true sense . 
The uplink rate generally refers to the speed of uploading from your computer, that is, the rate at which others communicate from your computer! 
The downlink rate is generally the speed you download from the host on the network! Generally, the upstream and downstream rates
 of ADSL Internet access are asymmetric, and the downstream rate is generally higher ! Upside is lower! Now the normal is up: 386Kb, down: 512Kb! Note that there is a difference between speed and actual speed! Generally, it needs to be divided by 8 , so the actual speed is only about 50K!