Dedicated Internet Access (DIA):

Unlike a simple Asynchronous Broadband connection from a cable provider or a DSL line, DIA is High speed, High availability, Synchronous connectivity from a customer's location to the Internet - No other company will share your DIA connection so again, unlike Broadband there is no degradation in speed at any given time of day where you often feel the speed decrease at peak usage times when using a Cable or DSL circuit. DIA is comprised of two separate components: the local loop and the DIA port. The local loop is the actual physical Copper or Fiber connectivity from your building to the carrier's Internet POP (Point of Presence). This loop can be provisioned over copper for port speeds up to 9M or so, or over fiber optic cabling for port speeds greater than 9M. The DIA port is literally the portal that allows for the Internet access. With connection speeds ranging from a 1.5M T1 loop to a multi-GIG OC-level circuit, businesses can choose the speed and price point that best suits them. DIA also supports VoIP and can have a carriers voice service and cloud offerings provided over it as well. 

Point to Point:

Point to Point circuits, also known as Private Lines, are circuits that are utilized as connectivity between two locations. Customers can utilize this technology to connect host and remote location or locations as a more secure dedicated WAN instead of using a potentially less secure connection such as VPN which crosses the public internet. Each point to point circuit is distance sensitive, meaning that the price for the circuit will be dependant on the mileage between the two locations that are to be connected. Point to point circuits can be provisioned in full bandwidth allocations ranging from T1/DS1 (1.544Mbps) to multi-GIG speeds.

VPN:

A VPN (virtual private network) is a way to use a public telecommunication infrastructure, such as the Internet, to provide remote offices or individual users with secure access to their organization's network. A virtual private network can be contrasted with an expensive system of owned or leased lines that can only be used by one organization. The goal of a VPN is to provide the organization with the same capabilities, but at a much lower cost. A VPN works by using the shared public infrastructure while maintaining privacy through security procedures and tunneling protocols such as the Layer Two Tunneling Protocol (L2TP). In effect, the protocols, by encrypting data at the sending end and decrypting it at the receiving end, send the data through a "tunnel" that cannot be "entered" by data that is not properly encrypted. An additional level of security involves encrypting not only the data, but also the originating and receiving network addresses.

DSL:

DSL (Digital Subscriber Line) is a technology for bringing high-bandwidth information to homes and small businesses over ordinary copper telephone lines. xDSL refers to different variations of DSL, such as ADSL, HDSL, and RADSL. Assuming your home or small business is close enough to a telephone company central office that offers DSL service, you may be able to receive data at rates up to 6.1 megabits (millions of bits) per second (of a theoretical 8.448 megabits per second), enabling continuous transmission of motion video, audio, and even 3-D effects. More typically, individual connections will provide from 1.544 Mbps to 512 Kbps downstream and about 128 Kbps upstream. A DSL line can carry both data and voice signals and the data part of the line is continuously connected. DSL installations began in 1998 and will continue at a greatly increased pace through the next decade in a number of communities in the U.S. and elsewhere. Compaq, Intel, and Microsoft working with telephone companies have developed a standard and easier-to-install form of ADSL called G.lite that is accelerating deployment. DSL is expected to replace ISDN in many areas and to compete with the cable modem in bringing multimedia and 3-D to homes and small businesses.

MPLS:

MPLS is a technology, not a service. Most carriers run MPLS underneath a wide range of services, including frame relay, wide-area Ethernet, native IP and ATM. The advantages accrue primarily to the carrier. User benefits include lower cost in most cases, greater control over networks, and more detailed QoS. In fact, QoS is the primary reason IT executives opt for MPLS - in a recent Nemertes benchmark, 62% of organizations told us they're using MPLS today or plan to deploy it, with 55% listing QoS as the main reason. 

MPLS-based services are a good fit in the following scenarios:

Your company has a lot of any-to-any traffic. Any-to-any traffic requires N-squared number of connections - an expensive proposition in network technologies that charge by the circuit, such as frame or ATM. Most companies don't have a lot of any-to-any traffic, unless they're engaged in a convergence project. The majority of today's applications tend to be client/server, which generate hub-and-spoke traffic patterns. For these, switching to MPLS doesn't buy much: Firms report around 10% cost savings as compared with legacy frame or ATM. But the scenario changes dramatically when MPLS is used to converge voice and video - or with next-generation software architectures. You're planning a convergence project. Most firms see immediate savings - 25% or more - when they begin combining voice and video traffic over the MPLS WAN. Video often is carried over ISDN circuits that are expensive. Consolidating this traffic onto a data network can eliminate the need for an ISDN network, generating immediate savings. Also, both video and voice tend to have any-to-any traffic patterns, unlike legacy data apps - so the any-to-any cost savings begin to kick in. You're planning to deploy next-generation computing infrastructure such as Web services, peer-to-peer or grid computing. Web services and peer-to-peer generate any-to-any traffic patterns; grid computing does the same, and often requires QoS capability. In fact, for some financial services firms, grid computing is the primary driver behind MPLS.