Sure! Here's a simplified diagram illustrating the basic architecture of an Internet Service Provider (ISP):

                        +----------------+
                        |     Upstream   |
                        |   Providers    |
                        +-------+--------+
                                |
                                |
                      +---------+---------+
                      |    ISP Core      |
                      +---------+---------+
                                |
                                |
                      +---------+---------+
                      |    Edge Router   |
                      +---------+---------+
                                |
                    +-----------+-----------+
                    |    Distribution Switch  |
                    +-----------+-----------+
                                |
                    +-----------+-----------+
                    |   Access Switch/DSLAM  |
                    +-----------+-----------+
                                |
                    +-----------+-----------+
                    |        Customers       |
                    +------------------------+

Explanation of components:

1. Upstream Providers: These are the higher-level service providers that connect the ISP to the wider internet. They supply the ISP with internet connectivity and serve as transit points for data traffic.
2. ISP Core: This represents the central core network of the ISP. It consists of routers, switches, and other networking devices that facilitate routing and switching of data within the ISP's network.
3. Edge Router: The edge router connects the ISP core to the external network. It handles the routing of data packets between the ISP's internal network and the upstream providers.
4. Distribution Switch: This switch manages the distribution of network traffic within the ISP's network. It connects multiple access switches or DSLAMs to the edge router.
5. Access Switch/DSLAM: These switches or DSLAMs (Digital Subscriber Line Access Multiplexer) connect the ISP's network to individual customer premises. They manage the network connectivity for customers and provide access to various services.
6. Customers: These represent the end users or subscribers of the ISP's services. They connect to the ISP's network via modems, routers, or other customer premises equipment (CPE) to access the internet.

Please note that this diagram is a simplified representation, and the actual architecture of an ISP can vary based on factors such as the scale of operations, technology used (e.g., fiber, DSL), and additional network elements employed for specific services (e.g., firewalls, load balancers).