如果没有理解错的话，应该是：我们有网络（或者是WIFI），可以上网，但是无法保证网速。

这句话说了网速没网吧里的好，但是可以上网，但网速不能保证

it means "we have wifi,but not so fast"

the sentence could mean here is Internet bar so here's computers can going Internet but speed maybe not fast.

here is not a place which only for sufing internet,but we can link to internet,but the speed is not for sure..... 网咖：Internet caf'e ，cyber café, but actually there is a place in China only have computer there....people who play computer games would like to go...because it is fast.....