Fraction of a Fractional T1?

[Technokrat]

When you purchase a fractional T1 line, let's say 128k, are you truly getting a dedicated 128k, or does it depend on the wording in the service providers contract?

I've heard the following, and was wondering if anybody heard the same, or something similar:

When you purchase a 128k line you are purchasing part of a potentially oversold T1 line (sharing the T1 line with other fractional T1 users), and that the 128k is a guaranteed burstable rate. So, as long as one time during a given month your able to claim (burst to) 128k of bandwidth, they have met their contractual obligation.

 

[johnny99]

I think T1 is basicly the same as E1 except that I think that T1 operates with 56Kbit/s timeslots and E1 with 64Kbit/s timeslots.

The connection you get is what you have in the contract. If your config says you have 2 timesslots (total 128Kbit/s) that is what you have on the point-to-point connection.

If your providor is overselling the connection it is not the line you are on but after the termination point of your line.
Your fration could come out of a E3 line in the providor end, but if he has all his customers on one E3 line but only a E1 to the internet he is overselling a lot.

But again, your timeslots are what you get. Not more not less. But it's on the point-to-point connection.

/johnny

 

[GunJack]

Johnny's correct in that you will have a full connection to your provider that is capable of 128K up to 1.5MBs. They will throttle you back on their side to limit how much you can send/receive.

One othe thing to consider is whether you are being sold a true point to point T1 or a frame relay connection. I'm seeing a lot of sales people push a "T1" connection which is really a Frame Relay connection that has a burst rate of 1.5Mbs. Frame is an entirely different animal than a true T1 so there are a lot of other considerations to look at it. With a T1, it's simply your bandwidth limit. With Frame, you have your burst rate, commited information rate, cloud latency, etc.. that all affect what you're really getting.

Hope this helps,
GJ