What is DSL ?
DSL is the abbreviated word for Digital Subscriber line, Digital subscriber line or DSL works off a DSLAM or Digital Subscriber Line Access Multiplexer which servers as an interface device connecting from your location to the carrier's closest network POP. DSL speed is affected by distance away from the carriers DSLAM.

Distance is usually measured in feet and up to 20,000 feet or 4 miles from the DSLAM (typically located in a Central Office)
20,000 feet would produce approximate bandwidth 128 - 256kbps - 768Kbps
15,000 feet would produce approximate bandwidth 500 - 768kbps -2 Mbps
10,000 feet would produce approximate bandwidth 1.1 - 2.5Mbps
5,000 feet would produce approximate bandwidth 1.5 - 3 Mbps
1,000 feet would produce approximate bandwidth 2 - 5Mbps

DSL is best used for residential or a web surfer, as the downstream is much faster than the out or upstream.
DSL is also prone to more technical glitches than T1 and has a lower priority of repair for the carrier.

We recommend going direct and using the local provider in your area for DSL, as they will offer the best QOS and customer service compared to a reseller.

What is a T1 ? or DS1 ?
T Stands for Trunk
DS stands for Digital Signal

T1 & DS1 are the same thing.

T1 & DS1 = 24 phone lines
or
T1 & DS1 = 1.544Mbps in Bandwidth
You see, each channel represents 64.33kbps x 24 = 1.54Mbps (combined bandwidth)

T1 or DS1 can be combined or integrated to share voice & internet over the one T1, DS1 or T3 connections.

What is PRI
PRI or Primary Rate Interface, the ISDN comparable to T1.
PRI provides 23+ 1 D channel.
The 23 channels can be used for calling; the D channel is used for signaling name/number caller id and maximizing the efficiency of the 23 channels towards what ever your use.
ISDN PRI is commonly used for Video Conferencing
PRI is used with 911 operators, call centers, businesses with computer & telephony integration it allows number/name & address information of the caller calling in which can quite easily pop up on the screen or be routed to the appropriate department.

What is an E1 ?
An E 1 is the European standard to the T1, however...
The E1 has 32 channels or 2.048 MBps or bandwidth
See T1 for reference.

What is a DS3 ? or T3 ?
T Stands for Trunk
DS stands for Digital Signal

T3 & DS3 are the same thing.

T3 & DS3 = 672 phone lines or 28 T1's.
or
T3 & DS3 = 44.736Mbps

T3 or DS3 can be combined or integrated to share voice & internet over the one T3 or DS1 connection.

What is an OC3 ?
Optical Carrier (Fiber) 3

3 DS 3's or 84 T1's or 155.52 Mbps. Typically used by Telecom carriers, ISP's, large financial institutions, .com's, schools,

What is an OC12 ?
Optical Carrier (Fiber) 12. Typically used by Telecom carriers, ISP's, large financial institutions, .com's

622.08 Mbps

What is an OC48 ?
Optical Carrier (Fiber) 48 typically used by Telecom carriers, large financial institutions.
2.4Gbps

What is an OC 192 ?
Optical Carrier (Fiber) 192
9.953 Gbps typically used by Telecom carriers