o/t...T1/2/3 internet connection

[Asterix]

...searched but couldn't find (both here and on wider t'internet), sure this has been discussed here before.

How can you tell if you have a T1, 2 or 3 connection?

[ACW]

Unless your a yank you dont got any of those.

[Asterix]

thx

[Richgm]

Speed wise they go like this:

T1= 1544kbps

T2=6312 kbps

T3= 44736 kbps

[Asterix]

...so is it a techhie standard that the uk can't use or just isn't marketted here?

[bill shurvinton]

We use E1, E2, E3 etc. In US the basic switched transmission building block is 1.5Mb/s, over here it is 2Mb/s. BT megastream is E1.

With the rise of DSL you are unlikely to use E1 unless you are a telco or big company anymore as it costs thousands.

[ACW]

E/T and J are heirachys of connectivity. All are built from 64K channels. In the USA the channels are 56K for data with 8K used for Robbed Bit Signalling / Channel associated signalling. For UK an E1 is 32 channels (timeslots of 64K) giving 2048K. E3's run at 45M.

As bill says most consumers and even companies now connect via DSL services. These generally are either SDSL in speeds of 512K, 1024K or 2048K in both directions.

In ADSL there are two variants now available. Regular ADSL and ADSL MAX. These should not be confused with ADSL2 which will become widly available in the future. Regular ADSL typically offers download speeds of 512K, 1024K and 2048K though speeds lower than this exist. The upstream rate is noramlly 288K.

ADSL Max which became widely availble around 8 months ago offers speeds up up to 8M downstream with two options for upstream of 448K and 832K. These are sold internally with BT openreach as IPStream home and IPStream office to wholelsale ISPs.

ADSL Max has some interesting issues over regular ADSL. Areas where is has not been possible to delivery relaible 512K ADSL Connections have been able to connect with MAX services at around 6M. however vice versa is also the case. BTs own tests have discovered ADSL MAX is vey sensitive to external noise and DSL fill in the trunk cabling (ie how many other subscribers in the same mutipair). In addiiton it is very sensitive to in house extension wiring. BT expect MAX customers who suffer from problems to be less than 1%. In our experience this has been as high as 30%.

ADSL2 which should start appearing in the near future is good to 24M. It is able to delivery higher bandwidth with more immunity to noise further. It should give 10M delivery to customer 2.5KM from the exchange and 2M up to about 5KMs.

ADSL2 requires a different modem / router interface to ADSL due to a different technology, where as MAX and ADSL1 should be ok with the same router. However bear in mind that the router hardware load of an 8M circuit is much higher than that of a 2M circuit.

[Mark Stanton]

Looks like Peter will be having an invoice land real soon from ACW                    

[Arm]

[Asterix]

Looks like Peter will be having an invoice land real soon from ACW                    

lol [bankrupt emoticon]

Top info though Adrian, just in time for the BT xmas party  

[ACW]

well it aint often someone asks me about summat I actually know.

[pistonbroke]

My new Belkin is beltin  

[CarlR]

You would have had E1 had you had Home Highway installed, E1 Basic Rate ISDN

E1 Basic Rate is 2 Bearer channels @ 64K and 1 Data channel.

[v7slr]

Dear Webmaster, what type of ADSL is Sky marketing at the mo? They claim I'll be able to get up to 16Mbit download although I can't find any info about upload speeds.

[adhawkins]

If memory serves, Sky bought Easynet. Is there anything on their site?

Andy