How does a Subscriber’s Internet travel from Service Provider Perspective#
As with everything it depends on the solution provided - Fibre, Adsl and Wireless technology like 3g, 4g and LTE
Looking from a Fibre perspective the flow is:
ONT -> OLT -> ENNI -> RADIUS -> BNG -> PACKET INTROSPECTION - P ROUTER - PEERING/IP TRANSIT
So let us go through what the above are:
- ONT (Optical Network Terminal) - device at subscriber’s home that converts optical signals into electrical signals
- OLT (Optical Line Terminal) - convert, frame, and transmit signals for the PON network and to coordinate the optical network terminals multiplexing for the shared upstream transmission
- ENNI (External Network-to-Network Interface) - The boundary between 2 operators. Layer 2 Vlan is handed off.
- Radius - Speaks to the BNG to authenticate subscribers
- BNG (Broadband Network Gateway) - the access point for customers to connect to the broadband network
- PACKET INTROSPECTION - Inspects all traffic and stores amount of traffic used for subscribers
- P ROUTER (Provider Router) - Provide reachability between Provider Edge devices
- PEERING / IP TRANSIT - IP transit is when one entity pays another for the right to transit its upstream network (One entity is higher than the other on the chain). IP peering is a mutual exchange of data between two ISPs.