ADSL is not symmetric and so can only transmit data upstream at speeds of 640Kbps - still 10 times faster than a single ISDN connection. ADSL, on the other hand, slows down to 16Kbps upstream and 2Mbps downstream over the same distance - although...
Fibernet is to launch a pilot scheme of symmetric digital subscriber line (SDSL) networks for telcos and ISPs and will, unlike ADSL, herald the arrival of both voice and data transfer of up to 2Mbits upstream as well as downstream.
ADSL is more suitable for residential users and small businesses as they would mostly use it for downstream access, that's to say downloading from the internet, but having upstream speed requirements of much less than 2Mbps," Johnson explains.
He added: "If this was going to be useful, BT would be supplying Symmetric DSL (SDSL provides broadband going to and from the consumer) for business users with guaranteed service levels. BT is promoting a 512Kb line, but it is Asymmetric DSL (ADSL...
Earlier this month, the telco said "symmetric broadband is ideal for business use as it supports applications that require the same upstream and downstream speeds. SDSL, or symmetric DSL, provides a two-way high-speed internet connection.
Apart from the asymmetry that typically sees 512Kbps downstream (from ISP to the customer) and 128 to 256Kbps upstream (from customer to ISP), there is the small matter of sharing. Second, asymmetric services also qualify.
Did you find this white paper useful? 
White Paper RSS
Download
Register
