T3 and DS3 are terms which in the field of telecommunication are often used interchangeably to describe a 45 mbps (megabits per second) circuit. A T3-DS3 is the equivalent of 28 T1s. People who are more technically inclined will often refer to DS3 when they are talking about the configuration of the circuit, and T3 if they are referring to the physical facilities which carry the circuit. Most people, however, use both terms interchangeably.T3 is a relatively large data bandwidth pipe which is commonly used for internet connectivity, voice lines, direct point-to-point connection between two business locations, Multiprotocol Label Switching (MPLS) networking between multiple locations of a business and integrated circuits which combine any combinations of these applications.
DS3 is a 45 mbps (megabits per second) circuit. A DS3, commonly referred to as T3, is the equivalent of 28 DS1s (commonly known as T1s). DS3 is commonly used for large: point-to-point (private line) circuits, MPLS (multiprotocol label switching) VPNs (Virtual Private Networks), internet traffic, call centers, video conferencing and broadcast quality video transmission. DS3 price is determined by market conditions, cost of facilities, and most important, distance from the point of presence (PoP) of the quoting provider. The further a business is from the PoP, the more it costs to extend a DS3 circuit to this business. Another aspect of DS3 price is the “build-out” of proper wiring to and at the served premise. DS3 requires special wiring. Most businesses are not properly wired, or “lit” for DS3. In these cases, installation of appropriate wiring can cost thousands of dollars. If the end user needs less than 12 mbps, bonded DS1 (bonded T1) can be a much less expensive alternative. Since a bonded DS1 circuit only requires two pairs of phone lines, it can be installed free of charge to virtually any business location in the US.