Cable Forum - View Single Post - 50M Think Broadband Ping Monitor Results (POST YOURS)

qasdfdsaq · 21-05-2012, 01:05

It's simply a difference in the way the technologies work and how much capacity is provided.

Openreach provide 20mbps dedicated upstream for every customer signed up to the 20mbps upstream service (or at least, that's their target). When a FTTC modem wants to transmit data, it has its entire upstream speed guaranteed to it and can transmit whatever it wants whenever it wants, instantly, with no delay.

VM provide 20mbps of upstream shared between several hundred users. In order to ensure it's shared properly, the modem needs to request permission to transmit every time it wants to send data, and then wait for the response, then finally wait for its allocated timeslot (if any) to do the actual transmission. This process takes a lot of time, and ultimately it may not get the time it requests because there's 200kbps of capacity per user or less.

21-05-2012, 01:05	#1414
qasdfdsaq cf.mega poster Join Date: Aug 2004 Posts: 11,207	Re: Think Broadband Ping Monitor Results (POST YOURS) It's simply a difference in the way the technologies work and how much capacity is provided. Openreach provide 20mbps dedicated upstream for every customer signed up to the 20mbps upstream service (or at least, that's their target). When a FTTC modem wants to transmit data, it has its entire upstream speed guaranteed to it and can transmit whatever it wants whenever it wants, instantly, with no delay. VM provide 20mbps of upstream shared between several hundred users. In order to ensure it's shared properly, the modem needs to request permission to transmit every time it wants to send data, and then wait for the response, then finally wait for its allocated timeslot (if any) to do the actual transmission. This process takes a lot of time, and ultimately it may not get the time it requests because there's 200kbps of capacity per user or less.