Broadband network architecture refers to the design and structure of the networks that deliver high-speed internet access to end-users. Broadband can be delivered via a variety of mediums including copper lines, fiber optics, cable, satellite, and wireless technologies. The architecture includes the physical components (like cables and switches) and the functional organization (like how data flows through the network).
Here’s an overview of the key architectures used to deliver broadband:
DSL (Digital Subscriber Line):
- Architecture: Uses telephone lines to transmit digital data.
- Equipment: Central office DSLAM (Digital Subscriber Line Access Multiplexer) connects to the customer’s DSL modem.
- Types: ADSL, VDSL, etc. vary based on speed and technology.
Cable Broadband:
- Architecture: Uses the coaxial cable infrastructure initially built for cable TV.
- Equipment: Central office houses CMTS (Cable Modem Termination System) connecting to the user’s cable modem.
- Protocol: DOCSIS (Data Over Cable Service Interface Specification) is commonly used.
Fiber Optic Networks:
- Architecture: Uses thin strands of glass or plastic to transmit data as light signals.
- Equipment: OLT (Optical Line Terminal) at the central office connects to ONT (Optical Network Terminal) or ONU (Optical Network Unit) at the customer premises.
- Types: FTTH (Fiber-to-the-Home), FTTB (Fiber-to-the-Building/Basement), FTTC (Fiber-to-the-Curb/Cabinet), FTTN (Fiber-to-the-Node), etc.
Satellite Broadband:
- Architecture: Uses satellites in orbit to relay data between a central ground station and user dishes.
- Equipment: Satellite dish at the user’s location connects to a modem inside the premises.
Wireless Broadband:
- Architecture: Uses radio frequencies to transmit data between a central tower and end-user devices.
- Equipment: Wireless towers equipped with base stations connect to user’s wireless routers or directly to devices.
- Types: Wi-Fi (for local areas), WiMAX (for broader coverage), LTE, and 5G are examples.
Hybrid Approaches:
- HFC (Hybrid Fiber-Coaxial): Combines the use of fiber-optic and coaxial cables. Fiber runs to a local node, and from there, coaxial cables connect to individual homes.
- G.fast: A protocol designed to provide fiber-like speeds over short distances of copper lines.
When considering broadband network architecture, several factors come into play:
- Infrastructure Costs: Initial investment needed for deployment.
- Maintenance Costs: Ongoing expenses to keep the network operational.
- Performance: Speed, latency, and reliability.
- Coverage: Ability to serve urban vs. rural areas.
- Scalability: Ease of expanding the network as demand grows.
The ideal architecture for a given region or application can vary based on existing infrastructure, topography, user density, and desired service levels.